travel through air and liquids

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Liquids Rule

You are allowed to bring a quart-sized bag of liquids, aerosols, gels, creams and pastes in your carry-on bag and through the checkpoint. These are limited to travel-sized containers that are 3.4 ounces (100 milliliters) or less per item. Placing these items in the small bag and separating from your carry-on baggage facilitates the screening process. Pack items that are in containers larger than 3.4 ounces or 100 milliliters in checked baggage.

Any liquid, aerosol, gel, cream or paste that alarms during screening will require additional screening.

• Medications
• Infant and child nourishments

Inbound International Flights

You may carry duty free liquids in secure, tamper–evident bags, more than 3.4 oz or 100 ml in your carry-on bag if:

• The duty free liquids were purchased internationally and you are traveling to the United States with a connecting flight.
• The liquids are packed in a transparent, secure, tamper-evident bag by the retailer and do not show signs of tampering when presented to TSA for screening.
• The original receipt for the liquids is present and the purchase was made within 48 hours.

The items inside the secure, tamper-evident bags must be screened and cleared. Any item that alarms or is unable to be screened will not be permitted in your carry-on bag. We recommend packing all liquids, gels, and aerosols that are over 3.4 oz or 100 ml in your checked baggage, even if they are in a secure, tamper-evident bag.

3-1-1 Rule for Liquids in Carry-on Bags

Find out what's allowed before you pack

When you're going through airport security on your next vacation or business flight, you might notice a posted rule by the Transportation Security Administration called the 3-1-1 Rule, which dictates how much liquid travelers are allowed in their carry-on bags. Still, you might not understand exactly what this regulation means for your traveling needs.

The 3-1-1 Rule refers to three core components that govern how many liquids you can bring in your carry-on bags: Each liquid must be in a 3.4-ounce or less container ("3"), all containers must be placed inside one clear quart-sized plastic bag ("1"), and each passenger is only allowed one plastic bag ("1").

In sum, the 3-1-1 Rule states that you can carry as much liquid as can fit inside 3.4-ounce containers that fit inside one plastic quart-sized bag; however, you can bring as much liquid as you feel comfortable carrying in your checked bags as long as these liquids do not violate other TSA regulations that dictate what you can and cannot fly with in general.

How to Pack Your Liquids in Carry-ons

Whether you're hoping to bring your favorite shampoo or conditioner on your weekend trip or need to take contact solution on your flight, you'll need to properly pack liquids to get them through the TSA security checkpoint without hassle.

You'll want to start by either buying travel-size bottles of your favorite products or by purchasing travel toiletry bottles , which you can buy online, at most supermarkets, or home goods stores, and filling them with enough of your favorite products to get you through your trip. Then pack each of these inside a quart-sized ziplock (or other sealable) plastic bag—you should be able to fit four or five.

It's recommended that you pack this bag of bottles in your carry-on last, on top of your clothing and other times, because you'll need to pull the bag out and put it in one of the security checkpoint bins to pass through the X-ray machine. You can also stow it conveniently in an outside zip pocket for easy access.

Liquids That Are and Aren't Allowed

You might be surprised to learn that you can bring travel-size bottles of alcohol in your carry-on or that you can't carry creamy dips or spread as a snack in your suitcase if it exceeds 3.4 ounces, but knowing these rules will help you avoid additional screening at the TSA checkpoint.

You can bring blenders (with blades removed), alcoholic beverages less than 3.4 ounces that do not exceed 70 percent in alcohol content, baby food, some canned foods, and even live lobsters, but you cannot bring gel heating pads, any wet foods that exceed 3.4 ounces, ice cream of any quantity, or firearms of any type. 

For a complete list of all items that are forbidden and permitted through TSA security checkpoints at airports, make sure to check out the TSA website before your flight—you can even snap a picture of an item you're questioning and ask them on the TSA Facebook page whether or not it is allowed.

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Airport Security Rules and Regulations

How to Pack a Carry-On Bag

Here's the 411 on the TSA's 3-1-1 liquids rule

We've all been there. Waiting in the Transportation Security Administration line only to hear agents call for a "bag check," often because a traveler had a liquid product in their carry-on that's over the allowed limit (or some sort of other prohibited item).

It's a process that can sure slow things down, particularly on the busiest travel days. As you pack for your trip and consider what to put in your carry-on or checked luggage, it's important to consider what the TSA's limits are for liquids and similar products.

Since September 2006, the TSA has gone by the 3-1-1 rule when it comes to those types of products, including items like toothpaste, shampoo, conditioner, mouthwash and lotion -- sunscreen included.

For more TPG news delivered each morning to your inbox, sign up for our daily newsletter .

In short, the 3-1-1 rule is: Each liquid you bring through the TSA checkpoint must be in a 3.4-ounce or smaller container ("3"), all containers must be placed inside one clear quart-size plastic bag ("1") and each passenger is only allowed one plastic bag ("1").

If you meet those requirements, you should get through security without issue. However, if your liquid items are larger than 3.4 ounces each, you'll have to leave them in your checked bag.

There are a few exceptions, though.

The TSA has kept in place a temporary pandemic exception to the rule, allowing up to 12 ounces of liquid hand sanitizer in carry-on baggage.

Part of this exception: The hand sanitizer will have to be screened separately since it's technically over the limit. You'll need to remove it from your bag before it goes through the scanner.

There are also exceptions for larger amounts of medically necessary liquids, gels and aerosols. You can bring those products in larger, "reasonable" quantities, the TSA's website says. However, you must declare those items to security officers at the checkpoint for inspection.

This could, obviously, take a little more time than if you're traveling without those items.

This exception doesn't include sunscreen, despite calls to relax sunscreen restrictions at TSA checkpoints. Like other liquid products, sunscreen bottles over 3.4 ounces must go in your checked luggage.

There are also many liquids you cannot bring with you .

You can bring creamy cheeses, liquid chocolate, liquid coffee, creamy dips and spreads, gravy, honey, hummus, ice cream, jam, jelly, juice, syrup, peanut butter, salad dressing, sauce, salsa, soda, soup and yogurt as long as they are in a container of less than 3.4 ounces according to the TSA .

Related: Should you get TSA PreCheck or Clear — or both?

And yes, you can bring your water bottle with you, even if it weighs more than 3.4 ounces — as long as it's empty. This can also be a great way to save money at the airport, since -- as the TSA points out -- many airports have filling stations for reusable water bottles.

When in doubt, consult the TSA's list of what you can carry through the airport and check with your airline.

Additional reporting by Clint Henderson and Sean Cudahy.

Everything You Need to Know About the TSA’s Liquid Limit

The tsa allows liquids under 3.4 ounces in your carry-on—but what’s considered a “liquid” isn’t always obvious..

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Don’t forget to remove your liquids when going through TSA screening.

Photo by Jaromir Chalabala/Shutterstock

Whether you’re a carry-on-only kind of person or not , knowing the Transportation Security Administration’s (TSA) liquid limits is essential for anyone who travels by plane in the United States. Yet understanding which of your toiletries, foods, and other items even count as “liquid”—let alone how best to pack them—can get confusing. Use this guide to understand the TSA’s rules and restrictions about liquids, common exceptions, and tips to help ensure your next airport security screening goes smoothly.

What is the TSA liquid limit?

The TSA’s liquid limit for carry-ons—known as the 3-1-1 rule—allows travelers to pack liquids, aerosols, gels, creams, and pastes under 3.4 ounces (100 milliliters) in their carry-on bags. Passengers are allowed up to one quart-sized bag per person , or roughly nine 3.4-ounce containers in a single quart-sized bag. Anything more will have to go in a checked bag or risk being tossed out.

If your liquids are stored in containers larger than 3.4 ounces, even if there’s only 3.4 ounces left inside the bottle, you can’t bring them through security.

Completely empty bottles, such as your reusable water bottle , are allowed through the TSA checkpoint since (spoiler alert!) they don’t contain any liquids at that moment.

Which toiletries TSA allows in your carry-on

The TSA allows all of the following common toiletries in your carry-on only in containers that are 3.4 ounces or less:

• Shampoos and conditioners
• Lotions and sunscreen
• Gel hair products

In other words: yes, you can bring toothpaste, deodorant, and sunscreen through TSA checkpoints but only if they are in travel-sized containers.

Powders and powder-like substances, including baby powder and some makeup items, aren’t restricted in your carry-on bag. But if you’re carrying more than 12 ounces (350 milliliters) of a powder, you’ll need to place it in a separate bin for X-ray screening, and it may be subject to additional screening—so it’s a good idea to budget an extra few minutes at the security checkpoint if you think this might happen.

Tips for packing your toiletries in your carry-on

To comply with TSA regulations, invest in small, reusable toiletry bottles, like these capsules by Cadence.

Courtesy of Cadence

Especially if you don’t have TSA PreCheck , it’s helpful to pack all of your toiletries in a quart-sized (or smaller) clear plastic toiletry bag for screening. Although improved airport technology means that far fewer air passengers (both in PreCheck and non-PreCheck lines) will have to take their liquids out out of their carry-on, it’s still helpful to have all of your liquids in one bag just in case you get pulled aside for additional screening. For an upgrade from that large Ziplock, we recommend the standard-sized Clarity Jetset Case from Truffle ($88), which has a clear window panel and is comparable in size to a quart-sized bag.

Since toothpaste is considered a liquid, paste, or gel by the TSA, most of us toss those tiny one-ounce tubes in our carry-on bags. However, if you want to ditch the hard-to-recycle packaging, consider toothpaste tablets, an ecofriendly alternative that’s not subject to the 3-1-1 rule. We like Humankind’s fluoride toothpaste tablets ($12), which resemble small mints and turn to paste when you crush them between your teeth. Matador has also recently released a reusable toothpaste tube ($10), which you can fill (and refill) with your regular toothpaste.

For travel toiletries that are easy to rebottle (like shampoo or body wash), consider investing in reusable bottles or containers so you can always keep your preferred brand on hand. Some of our favorite TSA-approved toiletry bottles include:

Buy Now: GoToob three-pack of 3.4-ounce bottles, $30, rei.com

These easy-to-fill, leakproof silicone tubes are ideal for shampoos, conditioners, lotions, and body washes. GoToob’s line comes in a variety of sizes, ranging from 1.7 to 6 ounces, and are easy to clean between refills.

Matador FlatPack

Buy Now: $13 for one or $35 for three, matadorup.com

Each three-ounce, TSA-approved bottle is made from a durable, waterproof, nylon-based fabric. Like GoToob, they’re leakproof and easy to fill, but thanks to their flexible, fabric-like design, they will shrink to their contents, taking up less space in your pack. >> Read the full review of the Matador FlatPack

Buy Now: $14 for one or $74 for six, keepyourcadence.com

The refillable travel containers by Cadence are small, leakproof “capsules” that click together with magnets. At 0.56 ounces, they’re best for makeup and toiletries you don’t need much of—like a weekend’s worth of shampoo or a week of that under eye cream you only need a dab of.

Foods are subject to liquid limits

The TSA’s 3-1-1 rule applies to food too, meaning you’ll need to make sure any foods that count as liquids, gels, or pastes (like yogurt, peanut butter, pâté, jams, or that tasty pimento cheese spread you tried to bring home from Charleston) are less than 3.4 ounces or packed in your checked bag. There are some exceptions, like frozen foods and juice for babies, and the TSA’s website is the best resource to check for specific items.

Exceptions to TSA’s liquids rule: Full-sized liquids that you can bring through security

The TSA has several important exemptions to its liquids rule. You’re allowed to bring full-sized bottles of the following:

Hand sanitizer: Due to the coronavirus pandemic, the TSA currently allows travelers to bring up to 12 ounces of hand sanitizer in their carry-on bags. These will be screened separately.

Medication: You’re allowed to bring medically necessary liquids, aerosols, and gels through security. This also includes the ice or gel packs you may need to keep your medications cool. You are not required to store these items in a plastic, resealable bag, but you should remove them from your luggage and let the TSA officer know what you’ve packed.

Baby formula and breast milk: Like medication, you can bring freezer packs to keep these items cool, and you should remove them from your luggage and notify an agent when you go through security. More baby-related exceptions? Gel or liquid-filled teethers and canned or jarred baby food.

Of course, the final decision on whether an item is allowed through the checkpoint rests with the TSA officer.

If you’re ever unsure about a specific item, the TSA’s website has a handy, searchable list of prohibited and allowed items worth checking before you travel. You can also now text the TSA with your questions.

This article was originally published in 2022. It has been most recently updated on March 21, 2023, with additional information.

UponArriving

TSA Liquid Rules Ultimate Guide (3-1-1 Explained) [2023]

Bringing your liquids through airport security is not always as straightforward as you might think.

There are several rules that apply when bringing your liquids through airport security checkpoints and, yes, many are obvious to those of us blessed with a shred of common sense.

But in some cases there are some less obvious restrictions that could apply to your liquids.

And when you start talking about things like baby essentials, medications, and liquids like alcohol, there are many lesser-known rules and exceptions that come into play.

Violating these rules can sometimes mean slowing down the flow of the screening checkpoint (something we all should want to avoid) but in other cases it could mean violating the law and you basically becoming an airport criminal.

And nobody wants that.

So it’s a good idea to get acquainted with how these rules work and in this article, I’ll give you a detailed breakdown of the 3-1-1 rule and also talk about the many different types of exceptions and additional rules that apply to different types of liquids such as medications and alcohol.

Table of Contents

What is the TSA Liquids “3-1-1 Rule?”

The TSA Liquids 3-1-1 Rule states that you can only bring liquids in containers no larger than 3.4 liquid ounces (100 milliliters) and that all of your liquid containers must fit “comfortably” into one clear, quart-size bag.

Where does the 3-1-1 come from?

It’s just an easy way to memorize the different requirements that make up the rule and I’ll hit on those below.

3.4 fluid ounces or (100 mL)

The “three” indicates that your liquids must be contained within a container no larger than 3.4 fluid ounces or (100 ml).

(TSA uses 3.4 ounces because it’s easier to remember but really  100 ml comes out to 3.3814 fluid ounces. )

One of the biggest things that people get confused about is that the 3.4 ounce requirement applies to the size of the container and not the liquid within the container.

So let’s say that you have a 6 ounce container with only 2 ounces of fluid inside.

You may think that because you have under 3.4 fluid ounces of liquid, you are good to go but because your container is larger than 3.4 ounces, you cannot bring that through TSA.

The other big thing to know is that this refers to fluid ounces which relates to volume and is very different from ounces used for weight.

Some products like honey could weigh 4 ounces but still fit inside of a 3.4 fluid ounce container. It helps to know how to convert ounces/grams to fluid ounces .

Tip: Use the free app WalletFlo to help you travel the world for free by finding the best travel credit cards and promotions!

1 quart-sized resealable bag

The first “one” means that your liquids must fit within 1 quart-sized resealable bag. Typically, this will be a clear Ziploc bag which just makes things easy for everybody.

The key thing to note here is that the containers must fit “comfortably” inside this resealable bag.

What does “comfortably” mean?

It basically just means that the bag is not bursting at the seams. (Think about how a pair of jeans should fit when you’re being honest with yourself about your waist size.)

If you are not able to easily reseal your bag, then your contents may not be fitting comfortably inside.

In such a scenario, it’s possible that a TSA agent could ask you to throw something out in order to allow your bag to comply with the rules.

In my personal experience, I have not seen a lot of TSA agents enforce the “comfortable” requirement very strictly but if you have bottles poking out of your liquids bag, I could see that being an issue.

1 quart size bag per person

The last requirement is that you are allowed 1 quart size bag per person.

The easiest way to comply with this is to simply separate your liquids bag from your carry-on and have one liquids bag in your bin when going through security.

Otherwise, it could look like you are trying to bring through two bags of liquids.

The best packing tip I have for this is to keep your liquids bag at the top of your carry-on so that you can easily retrieve it.

There’s nothing worse than scrambling to find that liquids bag while trying to get ready to go through a screening checkpoint.

TSA Pre-Check liquids rule

TSA Pre-Check allows you to bypass the main security line and pass through a screening line that is usually much shorter and quicker. This also means avoiding the full body scanner in many cases. It basically makes you a VIP when it comes to airport security checkpoints.

If you have TSA Pre-Check , you can take advantage of several benefits including things like:

• Shoes can stay on
• Belt can stay on
• Light jackets can stay on
• Laptops allowed to stay in bag
• Liquids (3-1-1) can stay in bag

That last perk is the most relevant to the liquids rule as you will not have to remove your liquids bag and place them in one of the bins when going through security. You can simply leave them in your carry-on and pass through the metal detector without any issue.

I highly recommend that you look into getting Pre-Check in order to expedite your security screening. It will only cost $78 for five years and all you have to do is pass a background check. You can also get it if you are approved for Global Entry ( read how to get approved here ).

New hand sanitizer liquids rule

Due to the ongoing threat of coronavirus and the potential threat of spreading germs throughout airports and aircraft, TSA recently implemented a change with respect to hand sanitizer.

Passengers will now be allowed to bring one hand sanitizer bottle up to 12 ounces. These larger bottles will be screened separately so just be aware that it could add some extra time.

What exactly is a “liquid?”

In some cases, what constitutes a liquid will be very clear.

For example, it’s pretty much common sense that water inside of a water bottle is a liquid. The same applies for cologne, mouthwash, etc.

But liquids also can include less-obvious forms like aerosols, gels, creams, or pastes.

This means that several common items you would be bringing along for your trip could be considered a liquid like: toothpaste , lotion , sunscreen, shaving cream, shampoo , conditioner, and others.

You can find travel-sized products for most of these so it’s usually pretty easy to bring along items that comply with the TSA liquids rule.

Other items

You need to be mindful of other items that could be considered liquids like deodorant . For example, the following types of deodorants will be subject to the 3-1-1 rule:

• and Roll-On deodorants

Prohibited items

Just because you have something like an aerosol and it is in a container no larger than 3.4 ounces, that does not mean that you can bring it as a carry-on.

There are quite a few prohibited items like aerosol insecticide, bear spray, etc. that are not allowed as carry-ons. In fact, some of those items may not even be allowed on the plane at all. This is a good place to search if you are in doubt about whether or not you can bring a particular item.

Be aware that some items like hairspray may even have size restrictions when packed in your checked baggage.

Foods can also be liquids

One aspect of the TSA liquids rule that throws a lot of people off is that they forget many foods also qualify as liquids.

Here is a non-exhaustive list of food items that will fall under the liquids rule:

• Liquid chocolate
• Creamy dips and spreads
• Mashed fruits such as applesauce
• Jam and jelly
• Maple syrup
• Oils and vinegars
• Peanut butter
• Wet pet food
• Salad dressing
• Salsa and sauces

Basically anything that is usually poured, scooped, squeezed, slurped, or mashed will be considered a liquid for TSA purposes.

If your food is solid on the other hand , chances are you can bring it through.

TSA rules for liquid medications

The liquids rule provides exceptions for medical supplies and medications .

TSA allows larger amounts of medically necessary liquids, gels, and aerosols in “reasonable quantities” than your 3-1-1 allowance.

You do not have to have a prescription for these items but keep in mind that you need to comply with state laws regarding prescriptions and controlled substances.

This leaves two questions often to be asked and answered.

The first is what is considered “medically necessary?”

For example, is contact lens solution medically necessary?

It seems the answer to that is probably yes given the TSA states, they allow “larger amounts of medically necessary liquids, gels, and aerosols in reasonable quantities for your trip” on the page regarding contact lenses.

So if in doubt check the website and then inquire with AskTSA if you still don’t know.

The second question is what is considered a “reasonable quantity?”

What is deemed as a reasonable quantity is a subjective determination.

According to the TSA, you should bring what’s necessary for the duration of your trip (e.g., seven days) plus a day or two just in case things get delayed or canceled.

If you stick to what you think will be necessary for the duration of your trip, I don’t think you will often run into trouble. But if you’re bringing a six month supply of medication on a four day getaway, that’s when you might start to run into trouble if questioned.

TSA states that you must declare them to TSA officers at the checkpoint for inspection.

You also want to remove these from your carry-on so that they can be screened separately from your belongings. (You do not have to put your liquid medication in a plastic Ziploc bag.)

Just be aware that if one of your liquid items declared as medically necessary sets off the alarm, it may require additional screening and may not be allowed.

Baby essentials

You are allowed to bring formula, breastmilk, and juice for infants or toddlers in “reasonable quantities” through airport security. According to the TSA, reasonable quantities for baby essentials typically means the duration of the flight.

When bringing these items through security, be sure to separate these from your carry-on bag so that they can be screened separately from the rest of your items.

If you are carrying liquids in excess of 3.4 ounces, you are advised to inform the TSA officer at the beginning of the screening process that you have excess liquids. You can do this when you are unloading your items into the bin.

In many cases, excess liquids will be screened by x-ray.

It’s also possible that an officer may ask you to open up the container and potentially even transfer a small quantity of the liquid for testing.

If you are worried about the effects of an x-ray machine on your liquids, The Food and Drug Administration states that there are no known adverse effects from eating food, drinking beverages and using medicine screened by X-ray.

If that is not good enough assurance for you, you can ask to avoid the x-ray machine.

Additional steps may be able to be taken to clear the liquid but the traveler will likely have to undergo additional screening procedures which could include a pat down and a thorough screening of all of your carry-on property.

You will also be allowed to bring along ice packs, freezer packs, frozen gel packs and other accessories required to cool formula, breast milk and juice.

If these are in a partially frozen state or perhaps appear like a slushy they will be subject to the same screening as described above.

Other permitted baby items include gel or liquid-filled teethers, canned, jarred and processed baby food.

Just always be aware that these items may have to undergo additional screening.

TSA liquid rules for alcohol

Bringing alcohol through TSA presents a number of different challenges.

First, your alcohol in most cases will have to comply with the liquids 3-1-1 rule. This means that you won’t be able to bring in regular bottles of liquor or beer.

It is possible to find small bottles that are under 3.4 ounces (mini-liquor bottles are often around 1.7 ounces, so this means that they are small enough to be brought on the plane as a liquid).

But contrary to what many people think, it’s also permitted to bring your own alcohol in one of your own containers.

The catch is that there are specific restrictions about what type of alcohol is allowed on board and that can be allowed as a carry-on. You really need to make sure that you are abiding by these rules because you could be violating federal law otherwise.

The first regulation to know is that alcohol beverages with an alcoholic percentage above 70% (140 proof) is never allowed on the plane . In fact, alcohol with such a high alcohol percentage is considered a hazardous material.

If the alcohol content is above 24% but not above 70% then the alcoholic beverage must be in its retail packaging. A lot of popular alcoholic beverages for within this range. Here are some  ranges  for the alcoholic content of some common beverages:

Alcohol Percentage Content

• Vodka | ABV: 40-95%
• Gin | ABV: 36-50%
• Rum | ABV: 36-50%
• Whiskey | ABV: 36-50%
• Tequila | ABV: 50-51%
• Liqueurs | ABV: 15%
• Fortified Wine | ABV: 16-24%
• Unfortified Wine | ABV: 14-16%
• Beer | ABV: 4-8%
• Malt Beverage | ABV: 15%

And finally, one of the most important things to remember is that you are not allowed to serve yourself your own alcohol when flying.

Instead, you must request a flight attendant to serve you the alcohol or else you will be violating FAA regulations. Some flight attendants will happily serve you your own beverage but others will not be so inclined.

If you purchased alcohol at duty free store, different rules apply in that scenario. Basically, you can bring your duty free alcohol through TSA security but you have to comply with three separate requirements:

• The duty free liquids were purchased internationally and you are traveling to the United States with a connecting flight.
• The liquids are packed in a transparent, secure, tamper-evident bag by the retailer and do not show signs of tampering when presented to TSA for screening.
• The original receipt for the liquids is present and the purchase was made within 48 hours.

Read more about this rule  here .

Checked baggage liquid rules

Many times, you can simply place your liquids in your checked baggage and not have to worry about that pesky 3-1-1 rule.

This is usually the way to go on longer trips when you might be bringing large quantities of things like shampoo or shaving cream.

But as mentioned above, you still need to make sure that the type of liquid is allowed on a plane. Certain materials may be considered hazardous and you could be violating the law by bringing those on board.

If you are loading up your checked baggage with a bunch of liquids, make sure that you double bag if there is potential for the liquids to spill!

TSA Liquid Rules FAQ

The TSA 3-1-1 rule does not apply to checked baggage. However, there are some restrictions on what liquids can be transported in your checked baggage. There may also be limitations on the quantity of liquids when it comes to importing large quantities of things like alcohol. At some point, you might have to obtain a license for certain goods.

TSA definitely enforces the liquids rule and I would recommend not trying to circumvent the rule. It’s possible that an agent may be more lenient than another in certain circumstances but I would always assume that an agent will be enforcing strictly so that I don’t run into any unexpected issues.

TSA has the rules in order to detect potential explosives and other harmful materials that exist in liquid state.

The same liquid rules apply for both domestic flights and international flights. One difference that you might encounter is when you purchase duty free goods before an international flight. See the duty-free section above for more details. Also, when flying internationally it is recommended that you get to the airport extra early. It is possible that you could get hit with SSSS and be forced to undergo a heightened security screening, so always plan out extra time.

While you might view your makeup as special, there are no special rules for your makeup when it comes to TSA. They must abide by the same 3-1-1 rule explained above. Read more about makeup rules here.

No, you do not have to take out your liquids if you have TSA Pre-Check.

The same TSA liquids rule will apply to all airlines. So if you’re flying American or Delta, the rules will be the same as if you were flying Southwest or United. With that said, some airlines do have some differences in how they handle acceptable baggage so you should make sure to read up on the latest baggage policies for the airlines.

If you are traveling from an “international last-point-of-departure” to the U.S ., powder-based substances in carry-on baggage greater than 350mL or 12 oz. may require additional screening. If your substance is over 12 ounces and cannot be cleared it will not be allowed onto the aircraft cabin. TSA recommends that you transport powders in your checked baggage.

TSA has several rules you need to follow when it comes to drinking liquids through airport security. The most well-known is the 3-1-1 rule but there are other considerations you need to think about like foods that might trigger the rule and exceptions for medical and baby essentials. In the end, try to be as reasonable as possible with what you are bringing through and you will run into few problems.

Daniel Gillaspia is the Founder of UponArriving.com and the credit card app, WalletFlo . He is a former attorney turned travel expert covering destinations along with TSA, airline, and hotel policies. Since 2014, his content has been featured in publications such as National Geographic, Smithsonian Magazine, and CNBC. Read my bio .

I will be traveling from Mexico April 25th. Will I be able to bring back a bottle of Tequila in my check in luggage probably wrapped safely? Thanks, Regina Green

The above is good detail but how about: electric shaver and charger electric toothbrush

Yes and yes!

Check these out:

https://www.uponarriving.com/tsa-rules-razors/ https://www.uponarriving.com/tsa-toothpaste/

I will be leaving Chicago going to Manila via Istanbul on 21 July 2022, Turkish Airways. I will be bringing 4 bottles of Scotch whiskey in original container, unopened and sealed and properly packed with bubble wrap. Is this allowed?

How do I know which states allow medication‘s to be in a travel organizer, and not in their original bottles? I am flying from Philadelphia with a layover in Ireland, and finally to Paris on Aer Lingus.

Hand sanitizer rules have reverted back to the 3-1-1 guidelines.

Thanks for this update. Do you have a source on that? Couldn’t find updated info.

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Calling All Travelers: These Are the Official TSA Liquid Rules

You don't want security to throw away your new, full-size bottle of shampoo do you?

Every item on this page was chosen by a Town & Country editor. We may earn commission on some of the items you choose to buy.

We've all fallen victim to TSA while traveling; here's a refresher so you don't make the same mistakes again.

TSA Liquid Rules:

According to the TSA website , these rules apply for liquids, aerosols, gels, creams, and pastes.

All liquids must be in a 3.4oz or smaller container. Your serums, creams, cleansers, and masks are too expensive to lose, so check their sizes and if they're too big, leave them at home or transfer them to a smaller container.

They have to be able to fit in a quart-size bag. Before you throw 10 containers of liquids into your carry-on, make sure that everything can fit in a quart-size bag. Think about what you really need for your trip, a la Marie Kondo , and remember you can always buy things once you arrive at your destination.

Powders must be in 12oz containers or smaller. TSA placed new restrictions on powders in 2018. Ensure that your makeup, protein powder, and baby powder are in containers within that range, or put them into a checked bag.

Travel-Size Beauty Essentials

Drunk Elephant The Littles™ Set

Sunday Riley Power Couple Kit

Drybar The Four Pack

Ole Henrikson Truth Serum®

SK-II Facial Treatment Essence Mini

LA MER The Moisturizing Soft Cream

Fresh Rose Deep Hydration Toner

LE LABO Santal 33 & AnOther 13 Set

Kiehl's Since 1851 Super Age-Correcting Collection

Shiseido Urban Environment Oil-Free Sunscreen

R+Co Television Perfect Hair Shampoo

COOLA Suncare Sport Sunscreen Spray SPF 30

Anything else has to go into a checked bag. If you can't part with your full-size products, they have to go into a checked bag to avoid getting tossed into the TSA product graveyard. If you're looking to save money, share one checked bag with your whole group.

Only empty water bottles will pass the TSA checkpoint. If you bring a refillable water bottle, make sure it's empty before you approach security. You can fill it up after you go through the checkpoint or buy water in the terminal.

There are exemptions. If you use a medication that comes in liquid, aerosol, gel, cream, or paste form and the container is larger than 3.4oz, it's exempt from the above rules. Similarly, if you're carrying baby formula, breast milk, or other liquid foods for your child, these are also exempt.

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• Travel Tips

Everything You Need to Know About TSA Liquid Rules

Here's what to know before you fly with shampoo, medication, or any other liquids you may need during your travels.

Dealing with airport security can be one of the more daunting aspects of air travel , from the detailed rules about what you can and can't bring on board to the long lines that often form at checkpoints.

One rule that frequently trips up travelers is the Transportation Security Administration's (TSA) 3-1-1 regarding liquids in carry-on bags . We're here to walk you through the finer details of the rule and provide helpful tips for packing liquids when you're flying.

What is the TSA's 3-1-1 rule?

In 2006, British security officials thwarted a plot to bomb an aircraft with liquid explosives carried on board. Since then, security agencies around the world have limited the amount of liquid passengers can bring through airport security.

For the TSA, which regulates travel in the United States, all liquids, gels, and aerosols must be in containers that are 3.4 ounces (100 milliliters) or less. All liquids must fit into a single, clear quart-size bag — passengers can only pack one of these bags in their carry-on.

The 3-1-1 designation is a simple way to remember these numbers: individual liquid containers must be 3.4 ounces or smaller, they must fit into one clear, quart-size bag, and there is only one bag allowed per passenger.

Liquids that do not comply with the 3-1-1 rule must be packed in checked bags, or thrown out at airport security. Some liquids, such as gasoline or other flammable liquids, are prohibited entirely, both in checked and carry-on bags. You can find a full list of permitted and prohibited items on the TSA's website .

If you're unsure if a specific item adheres to the 3-1-1 rule, you can always contact the TSA before your trip. "Tweet your questions and comments to @AskTSA or via Facebook Messenger , weekdays from 8 a.m. to 6 p.m. ET," TSA spokesperson Jessica Mayle tells Travel + Leisure . "You can also call the TSA Contact Center at 866-289-9673."

Are there any exceptions to the 3-1-1 rule?

The TSA does exempt some items from the 3-1-1 rule: medically necessary liquids, formula, and breast milk. You can bring more than 3.4 ounces of these liquids on board, but you may have to undergo additional security screening.

"Inform the TSA officer at the beginning of the screening process that you're carrying them," says Mayle. "These liquids are typically screened by X-ray, but TSA officers may also test them separately for explosives or concealed prohibited items. Officers may ask you to open the container and/or have you transfer a small quantity of the liquid to a separate empty container, or dispose of a small quantity, if feasible."

If you don't want your exempt liquids to be screened by X-ray, inform your TSA officer, and they will use alternative security measures to clear the items.

And that's not all. "There's an exception for hand sanitizer, which has a temporary 12-ounce limit," says Mayle. But as COVID-19 travel restrictions and protocols continue to lift, the temporary special case for hand sanitizer could change, too.

Another exception is liquids purchased after security in an airport. In domestic U.S. airports , you can bring nonalcoholic drinks and other liquid items purchased airside onto your flight. (This is not always the case in international airports.) Duty-free liquids, however, will be sealed in a tamper-safe bag before boarding — sometimes they're permitted in the cabin, and other times they may be stowed elsewhere on the plane.

Packing Tips for Liquids in Carry-on Bags

• While many products are sold in 3.4-ounce containers suitable for travel, not all of them are. Consider rebottling your liquids into travel-size, leak-proof cases.
• "Another way to save space in your quart-sized bag is to pack solid versions of products, which you can put in your luggage or carry-on bag without needing to place it in the quart-size bag," travel advisor Ateet Ahuja of Complete Getaways tells T+ L. "For example, you can bring a stick or solid version of some perfumes and shampoo bars instead of liquid shampoo."
• Buy your liquids, like shampoo or mouthwash, at your final destination. "While you'll spend a little extra, the cost far outweighs the potential of it spilling or leaking in your bag," says Ahuja.
• On that note, prepare for spills — Ahuja advises wrapping a small hand towel around your quart-size bag.
• Pack your nonliquid toiletries separately to save space in your quart-sized bag.
• Pack your liquids bag in an easy-to-access space, like an external compartment or the top of your carry-on bag. According to Ahuja, "This will save you time in the TSA line."

Plan, Ready, Go

Carry-On Liquid Success: Packing Tips & Must-Have Items

Packing carry-on liquids can be challenging. This guide simplifies the process, ensuring you fit essential toiletries in a one-quart bag. Master the art of selecting and packing your carry-on toiletries, and travel lighter with confidence.

Key Takeaways: Packing Toiletries for Carry-On Luggage

• Follow the TSA 3-1-1 Liquids Rule: Travelers can bring a quart-sized bag of liquids, aerosols, gels, creams, and pastes in their carry-on, with each item being 3.4 ounces (100 milliliters) or less.
• Choose the Right Bag: A clear bag, no larger than one quart, is the limit for taking on the plane. A 1-quart Ziploc bag is commonly used.
• Minimize & Optimize Toiletries: Focus on packing only essentials and consider using solid alternatives or utilizing your hotel’s amenities to save space in your liquids bag.

This post includes affiliate links. If you make a purchase through one of these links, I may earn a small commission at no additional cost to you. As an Amazon Associate, I earn from qualifying purchases.  See disclaimer.

The TSA 3-1-1 Liquids Rule

According to the United States Transportation Security Administration (TSA) , “You are allowed to bring a quart-sized bag of liquids, aerosols, gels, creams, and pastes in your carry-on bag and through the checkpoint. These are limited to travel-sized containers that are 3.4 ounces (100 milliliters) or less per item. Placing these items in the small bag and separating from your carry-on baggage facilitates the screening process. Pack items that are in containers larger than 3.4 ounces or 100 milliliters in checked baggage.

Any liquid, aerosol, gel, cream or paste that alarms during screening will require additional screening.”

What kind of bag should I use to pack toiletries in my carry-on luggage? 

For packing toiletries in a carry-on, use a clear bag no larger than one quart. While many “TSA-approved” bags are available online and in stores, some may seem larger than the limit. To avoid potential issues at security, a 1-quart Ziploc bag is a safe choice.

PRO TIP: Consider getting TSA Pre-check  or Global Entry  (which comes with TSA Pre-check eligibility) so that you can go through security without pulling your liquids bag out of your carry-on luggage.

Get the perfect packing list template

Want a simple printable packing list template? Just print it out and fill it out so you don’t forget anything you want to take on your trip. Get the blank printable packing list in the Plan, Ready, Go Etsy shop.

Looking for a digital packing list you can use on your computer or mobile device? The packing list spreadsheet includes two tabs to help you track everything you need to pack plus all of the things you want to buy before your trip. The packing list is pre-filled for a one-week trip and is fully editable so you can start from scratch or use the existing list as your starting point.

Get the packing list template spreadsheet in the Plan, Ready, Go Etsy shop.

Tips for packing liquids in carry-on luggage 

Packing all liquid toiletries in a quart bag can be tricky, but with the right strategies, it’s feasible. Here are tips to optimize liquid packing in your carry-on bag .

Cut your skin care regimen down to just the essentials 

Cleanser, toner/liquid exfoliator, facial moisturizer. When packing carry-on liquids, that’s all you need throughout your trip unless you’re traveling for longer than a week. If you have room in your liquids bag after you’ve put in everything else that you need to take, then that’s the time to add in things like spot treatments on overnight masks. 

To trim your skin care liquids even further, use facial cleansing cloths instead of packing liquid, gel or cream cleanser, or face wash. I never travel without these dry cloths that I buy on Amazon and activate with water . That way I can travel with the exact amount I need. They never dry out like the moist towelette ones. 

Tip: use a digital and editable packing list to stay organized and make quick adjustments to your list as you pack for your trip.

Cut your hair care regimen down to the bare essentials 

Only take what you absolutely need to care for your hair on your trip. For you, that might be just shampoo and hairspray.  

If you’re staying in a hotel, you can minimize the toiletries you pack in your carry-on by using the products the hotel provides. Or try a shampoo bar like this one and leave shampoo out of your liquid toiletries bag altogether. 

Use your trip to use up the last of your toiletries 

I love to set aside my last bit of eyeliner or a sample of a skin care product for a specific trip coming up. Then I take those with me on my trip and just throw them out before I come home. 

When you travel carry-on only, every bit of space you make for yourself (especially on a return trip when you might have souvenirs to bring back) can help. 

Replace as many liquid toiletries as you can with solids (or powders that travel well) 

There are a lot of liquid toiletries that you can replace with solid-form versions like solid deodorants, solid shampoos, etc. They don’t need to be packed in your 1-quart liquids bag, which will free up space for you. 

• This is my favorite solid sunscreen stick.  
• You can try this popular solid shampoo bar . 
• You can also get solid conditioner bars like this one . 
• You can even buy solid body lotion to help keep you moisturized while you travel. 
• If it works for you, instead of liquid foundation and concealer, use mineral makeup like this one .  

You’ll save so much space in your carry-on liquids bag.

Share toiletry space with your travel partner  

If you have a travel partner who uses very little in the way of liquid toiletries use him or her as your mule to get a few extra things on the plane. My husband’s liquids bag holds shampoo, toothpaste, and antibacterial ointment. That’s it. So, he usually also takes my shampoo and we share the toothpaste. Now that’s love!  

Buy toiletries at your destination

If you’re going to be traveling long-term you might opt to wait until you reach your destination to purchase some toiletries or over-the-counter liquid medications. 

For example, if you’re planning to spend several weeks in one place (or road-tripping at your destination) you could wait until you arrive to purchase things like shampoo, toothpaste, or sunscreen that you know you will use daily (or multiple times per day).

Toiletries and travel size liquids packing list ideas for carry-on travel

Use this list as a starting place for packing toiletries when traveling carry-on only. You can easily customize it for your own needs and how you like to travel. I like to minimize my toiletries as much as possible and go low maintenance for hair and makeup on my travels.

  Keep track of everything you’re packing with these blank printable packing lists .

You can purchase travel sizes of your favorite products or get some reusable travel-sized containers of various sizes so that you can just take with you a bit of your full-size products from home.

• This “Amazon’s Choice” set comes with many different kinds of containers in different sizes.
• These bottles are also really popular on Amazon.

Skincare products 

• Cleanse with these dry cloths you activate with water. They’re perfect for traveling light. 
• I swear by this day moisturizer with SPF 30. 
• And I never travel without my travel-size bottle of this liquid exfoliant . 

Hair care products 

• Try this solid shampoo bar , so you don’t have to pack it in your liquids bag. 
• This solid conditioner on Amazon gets great reviews. 
• I also usually take a small hairspray with me. I pick up travel-size versions of my favorites at the drug store.

Makeup 

Face makeup .

• I like to travel with a long-lasting concealer or foundation/concealer combo. This concealer is my favorite .
• I also like this “foundcealer.”   
• To cut down on the quantity of liquids you pack in your carry-on, you might want to try a powder mineral foundation like this one . 

Eye makeup 

• I prefer to keep it simple here. I like to pack a good affordable eyebrow pencil with a clear eyebrow gel like this one . 
• Then perhaps try an eyeliner like this one . 
• A good tubing mascara like this one will help prevent smudges. 
• If taking an eyeshadow, consider using a retractable eyeshadow stick. It’s less likely to break up during travel like a traditional powder eyeshadow. 
• Keep it simple with a flattering lip gloss like this . 
• Or perhaps even just use lip balm. I never travel without it, especially on those long, dry flights. 

Miscellaneous toiletries and liquids 

• Travel is the perfect excuse to use up those little toothpaste and floss samples you get from your regular dental checkups. 
• And we never travel without this little item to help remove stains, since at least one of us (me) is a pretty messy eater. 

Packing carry-on liquids FAQs

The TSA 3-1-1 liquids rule can be confusing when it comes to which specific items apply and which don’t. It’s important to remember and follow the TSA liquid rules for everyone’s safety and so you can get through the checkpoint without delay.

What is the 3-1-1 rule for flying with liquids?

The 3-1-1 rule refers to the TSA’s regulation that allows passengers to bring a quart-sized bag of liquids, aerosols, gels, creams, and pastes in their carry-on bag and through the security checkpoint. Each container within the bag must be 3.4 oz. (100 milliliters) or less.

Can I use any bag for my carry-on liquids?

While there are many “TSA-approved” clear toiletry bag options available, it’s recommended to use a clear bag no larger than one quart to avoid any discrepancies at security checkpoints. A 1-quart Ziploc bag is a commonly used and reliable option.

Are there any exceptions to the 3-1-1 rule for carry-on liquids?

Yes, there are exceptions to the 3-1-1 rule for carry-on liquids. These exemptions include medications and nourishment for babies and toddlers such as breast milk and formula.

Can I bring toiletries in my carry-on? 

Yes, you can bring toiletries in your carry-on. But you’ll need to take a little care with how you pack liquid toiletries for your flight. Follow the TSA 3-1-1 liquids rule for any liquids, gels, or pastes that you pack. Then you’ll sail through security with no problem.

Can I bring mascara in my carry-on? 

Yes, you can bring mascara in your carry-on. However, it’s important to note that mascara is considered a liquid, gel, or paste by most airlines. So, it must adhere to the liquid restrictions set by the airline or the security authority of the country you’re flying from. For the U.S., that means mascara must be in your 3-1-1 liquids bag and not just in a general makeup bag. It’s always a good idea to check with your airline or the security regulations of the country you’re departing from to ensure compliance.

Does toothpaste count as a liquid?

Yes, toothpaste is typically considered a liquid or gel by airline and security regulations. This means that if you’re bringing toothpaste in your carry-on bag, it must adhere to the liquid restrictions in place.

Final thoughts on packing toiletries in your carry-on 

Figuring out how to pack toiletries when traveling carry-on only can be a challenge…and it can also be highly personal. What works for one person may not work for you. 

You also might find that you enjoy the challenge of packing for longer and longer trips with a minimal number of toiletries. And certainly, with all the solid toiletries options available, you should be able to get any liquids you need into that 1-quart Ziploc bag. 

Do you have any tips or tricks for packing your toiletries when traveling carry-on only?

Related articles about traveling carry-on only 

• What to Take on a Flight (in Your Carry-on)
• How to pack a suitcase to maximize space
• Travel Essentials for Women
• The Best Tips for Packing Light and Traveling Carry-on Only  
• How to Pack Light for a One-week Trip  

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Darcy Vierow is a busy professional and travel planning expert with years of experience maximizing travel with limited time and on a less-than-average salary. Her tips have been published by Forbes, MSN.com, Yahoo! News, Yahoo! Finance, Aol, Newsbreak and GOBankingRates. Read more about Darcy Vierow .

Hello Darcy, loved reading your helpful articles. In one article you mentioned a Columbia rain jacket which I cannot find and I want to order it this week for an upcoming trip. Would you please tell me which Columbia rain jacket it is?

Hi, Valerie. I recommend the Columbia Arcadia II. I bought mine directly from the Columbia website. https://www.columbia.com/p/womens-arcadia-ii-rain-jacket-1534111.html .

Have a great trip!

I use contact lens cases for some of my lotions and moisturizers. I had an abundance of them leftover from the days when I wore contacts, so I began using them for travel. They are small, but can easily hold a week’s worth of moisturizer. Use different colored cases for different products, or label each one if you are afraid you won’t remember what is in each case.

That’s a great idea. Thanks so much for sharing!

Thank you for these great tips! Traveling to India and trying to wrap my brain around what to do for 20 hours and how to pack our carry ons just in case our luggage gets lost!

You’re so welcome! Have a wonderful trip.

Thank you Darcy. Traveling internationally for the first time. Of the sites I’ve read, yours was the most helpful regarding liquid carryons. Thanks again Joyce

Thanks so much for your kind words! I wrote this post because back when I went on my first international trip I also had trouble finding the information I needed to help me pack my liquids for carry-on only travel.

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How Sound Travels Through Solids, Liquids and Gases

• August 13, 2022

We love to work with sound. Many of us record our own music, podcast, or other forms of sound. Knowing how sound travels through different mediums will allow you to have better control over the sound that you generate. That is what we will be looking at today. How does sound travel through solids, liquids, and gases? 

Can the way that you produce sound and the medium that it moves in make a difference in the volume that you will hear? How does this change when it comes to the different mediums? Will the furniture in a room have any impact on the acoustics of the room? How can you change it to create the perfect recording environment? 

These are just some of the things that we will discuss today. Knowing how sound travels through solids, liquids and gases are not only interesting, but it can have an impact on the way we record sounds and how we change things up. 

Why Is the Way That Sound Travels Through Mediums Important? 

One of the main reasons why it is important to understand how sound acts, is that when you understand something better, you can control it. As a youngster, I loved swimming. I still do. But one of my main attractions was that underneath the water it was the one place where everything went quiet. It always felt like the world stopped and it was just me and complete calm. 

I loved my family but there was always so much going on that it was just a great place to just be with my own imagination and thoughts. I could make up imaginary worlds and people, and have millions of stories running through my mind. All because there was a lack of sound under the water. 

But in reality, when you look at how sound behaves in a liquid, scientifically, this should not be the case. In fact, there should be more sound under the water than there is in the fresh air. Why? And why doesn’t it work that way? I wanted to find out. 

For many of us who record sound, it is important to be connected to it. If you understand what makes something sound fuller, what makes a noise loud, and how things act, you can have better control and your recording will end up being closer to what you intended in the first place. 

You might be recording a podcast, but for some reason, your voice keeps sounding muffled, understanding sound can help you identify what the cause could be and how you can fix it. 

What Is Sound? 

To understand why sound acts differently in different mediums we first have to understand what sound is. 

First, you need to know that sound can not exist in a void. This is different from light that does travel through nothingness. That is why we can see light shining from space where there is a void and no atmosphere. But those that have been to space say it is completely quiet. It must be an almost eerie feeling. 

Sound happens when something creates a vibration. This is done through musical instruments, our voices, speakers, and many other things. This then causes the medium around it, like the water or the air, to also vibrate and carry this sound with them. Without a medium, sound would not exist. That is because the molecules of the medium react and bump into those next to it and this allows the sound to travel on. 

At the same time, the medium that is used will determine just how loud the sound will be, it will also determine how far can travel and how the sound will generally react. This is because different solutions will have molecules that are more or less densely packed. 

Your surroundings will have a big impact. People who create a sound studio try to make the acoustics of the room as powerful as possible. This should help you do that. 

Let us now look at the three mediums that sound can travel through, solids, liquids, and gases, and how they change the reaction of the sound. 

First up we can look at gasses. You might wonder why gasses are mentioned when speaking of mediums that sound can move in. You may be visualizing a bunch of fog at a concert that makes the lights look incredible and makes the crowd go wild. 

And that is one possibility of gasses that can be used as a medium for sound to travel through. But most of the time, our air is the only gas that sound needs to continue its vibration. 

What Is the Air Made Of? 

We have already mentioned that sound can not exist in a void. But we can hear each other when we speak out in the open. We can hear music when it is being played under the starry sky and we can even hear kids shouting in a park a block away . 

That is because most of the air in our atmosphere is made up of gasses. Our atmosphere is not just a void, or we wouldn’t be able to live here anyway, but is made up of lots of gasses we can’t see. The atmosphere is made up of 78% Nitrogen, and 21% Oxygen, and the rest is a mixture of carbon dioxide, neon, and hydrogen. 

This gives us all the ability to breathe without needing a space suit, but it also gives sound the ability to travel in our atmosphere. We make a vibration and the molecules of the gases that we can’t even see start to bump into each other and takes that vibration further, making it possible for us to hear sounds. It is pretty amazing when you think about it. 

How Does Sound Travel Through Gases? 

Gas is the medium that will have the slowest speed of sound of all of them. This is because the molecules of the gases surrounding us are expanded and far away from each other. The vibrations do get passed over to each other but it takes longer to do. 

This is also why we often need things that can amplify our sounds like a microphone when we are speaking to a bigger group of people. These help us to make the vibrations bigger and to allow them to travel further than we would have been able to achieve with only our voice. 

Some Things That Can Influence Sound in Gases 

Have you ever felt that things are so much quieter after a big snowstorm? How the world seems almost different then? Turns out it might not just be your imagination. This is because the volume and speed of sound can be impacted by the temperature of the air and in turn the gas that is surrounding us. 

At lower temperatures, the molecules move around quicker and they can vibrate quicker. The energy behind the sound can start to be lost and the sound will become quieter or be lost faster. 

At normal room temperatures, the speed of sound will be a lot higher than it would be in the exact same room when the temperature is at freezing. 

There are many different liquids that have a higher or lower density but for the most part, it is in water where we would be interested in hearing a sound. If we go swimming or put a small portable speaker close to the water, we would like to hear the sound as loud as possible. But it just doesn’t always work like that. 

Let’s see how sound reacts in water or other liquids. 

Sound In Water 

The molecules in water are a lot more tightly packed than it is in gas. That is why sound travels much faster in water than it would travel in the air. Sound can actually travel in water almost four times faster than it can be in the air. 

That is really impressive. And still, if you submerge your head underwater, you will hear the sound but it might sound muffled and not quite like the sound that you are used to. 

Why Humans Hear Muffled Sounds in Water 

The water molecules are more tightly packed and the energy that it uses to carry sound is transported faster. In theory, you should be able to hear noises a lot louder when you are underwater. But that is not how we perceive this sound. 

This is because our ears are created to listen to sounds in the air. We pick up on sounds through our ear canal and these sounds are then transported to the brain that makes sense of it all. When you only submerge your ears, sounds will sound very muffled since the ears can’t take these sounds along the ear canal. 

When you submerge your head fully suddenly the sound is clearer and louder. Although it could still be somewhat muffled compared to outside the water. Our heads contain a lot of water, and inside the water, it will be our tissue that picks up on the sound and detects it. 

You could try to plug your ears but it will have very little effect on the volume of the noise under the water. The sound is not traveling along those normal lines. 

At the same time, chances are that it is also very hard and almost impossible for you to figure out from which direction the sound is coming. When the sound travels along the normal route our brain has cues to determine if it comes from behind us or in front. But when the sound does not travel in those normal routes the brain has no way of telling us where it is coming from. 

For humans communicating through sound under the water is not so easy. That is why divers have always used hand signals to communicate with their diving partners and why some have even started to use microphones that connect them. Allowing for a much better communication route. 

We know that we can’t hear sound in the same way when we are inside water as when we are in the air. But what happens when we make a big sound inside the water, like shouting? Will someone that is on the outside be able to hear it clearly? 

This is unlikely. That is because the surface of the water almost acts as a mirror for sound. Instead of the vibration moving outside of the water it gets reflected back. Making sure that very little sound is heard outside. 

Animals In Water 

Our ears might be designed to hear in air, but fish and mammals that live in the ocean can take advantage of the speed of sound inside the water. They are adapted to hearing noise completely clearly inside the water. 

Since sound does travel quickly in water and they can hear it, they can use sounds to communicate over much larger distances than we are able to do with just our voice. Whales, for example, have been known to use their voice to communicate with other whales over massive distances in the ocean. The sound of a humpback whale can travel thousands of miles in the ocean.  It also helps that the vibrations they can create are much larger than the ones our own vocal cords can produce. 

Then finally there are solids and how sound reacts when they come into contact with a solid. Since sound starts to get muffled when there are a lot of solid objects in its path you would think that it travels a lot slower in solids. But surprisingly that is not the case. There are however reasons why it reacts in this way. 

The Speed of Sound in Solids 

A solid object is densely packed with its molecules. Each solid object will be a little bit different from the other depending on the material it is made of and how densely packed its molecules are. There are some materials that will work better as insolation to noise than others, but we will discuss the reason for this shortly. But for the most part, sound will travel a lot faster in solids than it will in both liquids and gasses.

This is because the source of the sound will create the vibration in the molecules of the sound and then these tightly packed molecules will quickly send the vibration further along. This means that the speed of sound is a lot faster when traveling in a solid object and that it will be a lot louder too. 

Often a solid object will be a good source of amplification for a sound that you would like to enhance. The sound through a brass bugle gets enhanced through the design of the object and also through the material it is made of.

Examples Of Sounds in Solids 

It can be hard to think of examples where solid objects are used to move sound and make it louder. Let’s discuss some simple examples of this. 

You can put an ear to a solid object like a table and then make a soft tapping sound on the table. Compare how you heard it when your ear is on the solid compared to how loud it is when you hear the sound through the air. You will be surprised by how clearly the sound is enhanced by listening to it through a solid object. 

Another great example of an experiment that many of us probably unknowingly did as children is a string telephone. You take two cups and a long line of string. The two cups are each connected to one side of the string, one person listens into one cup while another speaks into the cup at their end. 

In this experiment, the vibrations are created and enhanced by the shape of the cup. Then these vibrations are transferred with the help of a solid object, the string, and the other person can hear your message at the other end of the string. Without raising your voice or shouting. 

It is always amazing to see just how far this simple design can carry sound. Fun fact, the world record for the longest-ever string telephone, which was made with tin cans, was a whopping 796 feet long. That is almost the distance of three football fields. That is a long way for a piece of string and two cups to carry sound. 

Then another great example of a sound being a lot louder when it is carried through a solid object is sounds that you can hear in the air. For example, hearing the sound of a horse coming closer, its hooves beating down on the ground. 

It is already a pretty impressive sound when you hear it in normal circumstances. But try putting your head to the ground and listening to the approach in that way. The sound is much louder and you can almost feel the vibrations that are making the sound you hear. 

Why Does Sound Get Muffled Through a Door? 

We know now that sound travels much faster through solid objects than it does through gasses or liquids. You would think that a solid object like a wall or a door will enhance the sound but the opposite is true. A sound that is coming from a different room is more muffled. 

If there is a lot of noise outside your home, for example, the neighbors having a party, it works to close the doors and windows and the sound won’t bother you as much. Even if you only have standard windows and doors. 

How does that work? It works because the sound you are hearing does not originate from inside a solid object. It traveled through the air until it came to your door. There it encountered a solid object. And instead of making the vibrations louder this change in medium made the sound lose some of the energy that it was traveling with. This reduces the level of the noise and makes it less noticeable when there are doors that are closed. 

Why Rooms Echo 

This change in energy is also one of the reasons why a room will or won’t echo. When you go into an empty room there is a good chance that you can create an echo. That is because the empty room has no solid objects that break the energy of the noise down and stop it. 

The vibrations bump only against the walls and reflect back. If you have a room that is still echoing even after your furniture has been installed, then there might not be enough solid objects that stop the speed and the energy of the sound. Something like a carpet that can absorb the vibration can help to stop the echo in the room. 

How Sound Travels Through Solids, Liquids, and Gases 

Sound needs a medium that can take the vibrations and move them along, allowing us to hear the sounds that are being created. 

When it comes to the speed of sound, a solid object will allow the vibration to move much faster since it has the most densely packed molecules. It will also make the sound the loudest. After solids, liquids have the highest speed of sound. And then finally gas, that included our air since it is made up of gasses. 

When a sound is traveling through one medium like air and then encounters another, like a solid door, it loses some of its energy and some of the volume will be lost. That is why solid insulation against sound is still one of the best options despite solids being a good conductor of sound. 

We might not be able to take full advantage of the high speed of sound that can be found inside a liquid, but those living in the ocean sure can and that is why whale sounds can travel thousands of miles under the water. 

Knowing how sound reacts to different mediums will allow us to understand it better. And that means that you should have better control over your recordings and all the ways that you like to create your own very unique sounds.

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The U.K. Ended Its Travel-Size Liquid Rule for Carry-Ons—Will the U.S. Do the Same?

By Jessica Puckett

Passing through airport security in the U.K. is about to get easier and more streamlined, as U.K. officials announced that the rule mandating liquids in carry-on bags be 100ml (3.4 ounces) or less will no longer be enforced, starting in June 2024. 

When the rule ends, passengers will be able to carry-on liquids measuring up to two liters in volume, the BBC reports . Additionally, passengers will no longer need to remove electronics from bags, such as laptops. Previously, major airports in the U.K., such as London Heathrow, were known for their stringent enforcements of the liquid rules.

In the U.S., similar policies are still in effect at airports around the country, with the TSA enforcing its so-called “ 3-1-1 ” liquid rule for carry-on bags: all liquids must be 3.4 ounces or less and fit in a single, one-quart clear bag. (Though there are  some exceptions to those rules.)

The more relaxed screening policies in the U.K. are possible thanks to new X-ray scanners that use computed tomography (CT) technology to produce more detailed, 3D images of luggage contents. (The technology is similar to a CT scan you might get at a hospital.) Most airports in the U.K. will need to upgrade their X-ray machines to the newer high-tech versions by June 2024. 

The same enhanced CT technology has been in use at U.S. airports for several years now, with the TSA rapidly expanding the scanners to dozens of airports nationwide. As of May 2022, the agency said it had deployed at least 402 CT units to 163 airports around the country. Over the summer, officials installed more of the scanners at additional airport checkpoints in anticipation of an uptick in air travelers, including at Billings Logan International Airport in Montana , Albany International Airport in New York, Buffalo Niagara International Airport in New York, Cincinnati/Northern Kentucky International Airport and Raleigh-Durham International Airport in North Carolina, the TSA  said in a release . 

With that in mind, will the TSA follow the U.K.’s lead and ditch its rules for carry-on liquids? Currently at U.S. security checkpoints with CT scanners, passengers already have somewhat more relaxed screening rules, as they aren’t required to remove their travel-size liquids, electronics, or food from their carry-on bags, according to the TSA. That was a precursor step to the new U.K. policy at  London City airport , which received CT scanners in November 2022 and announced that passengers no longer had to remove any items from their bags. 

But some industry analysts say scanning equipment is only one piece of the puzzle . “I believe that TSA and other aviation security organizations will study the results from the UK’s decision closely and carefully,” says Henry Harteveldt, an aviation expert and president of Atmosphere Research. “If behavioral profiling and other similar tools allow security organizations to potentially detect people who may pose a danger to airline crews and passengers, it may help reduce the need for measures such as the 100ml limit on liquids and the TSA’s 3-1-1 policy.”

Indeed, it seems U.S. officials plan to take it slow when considering any changes to the current TSA 3.4-oz liquid rule, which has been the international standard since it was implemented in 2006. “Computed Tomography technology produces 3-D images that can be rotated and combined with advanced detection algorithms to produce a substantial improvement in security screening,” Robert Carter Langston, TSA's press secretary, said in an emailed statement. “While we have them deployed at more checkpoints, we are years away from announcing a change to the current liquids rule.” 

Although U.S. passengers still need to pack travel-size liquids for the time being, that doesn’t mean that the security checkpoint hasn’t been seeing other improvements. Aside from rolling out more CT scanners, TSA has been deploying credential authentication technology: new ID scanners that don’t require passengers to show their boarding passes . Earlier in 2022, the agency also began accepting digital IDs from the Apple Wallet app at certain airports and testing an expansion of facial recognition to whisk travelers through even faster.

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Exploring Sound Transmission in Liquids: Wave Behavior, Reflection and Refraction, and Measurement of Liquid Properties

By Happy Sharer

Introduction

Sound is a form of energy that travels in waves and can be heard when it reaches a person’s ear. It can travel through air, water, and other substances. This article will explore the physics of sound traveling through liquids, including how it moves through water, factors that affect its speed, acoustic properties of different types of liquids, and use of sound waves to measure liquid properties.

Exploring the Physics of Sound Traveling Through Liquids

When sound waves pass through a liquid, they interact with the molecules of the liquid and create a series of compressions and rarefactions. This interaction causes the sound wave to change direction and speed. The behavior of sound waves in liquids depends on several factors, including the density and viscosity of the liquid, pressure, and temperature.

Wave behavior of sound in liquids

When a sound wave passes through a liquid, it is bent or refracted due to the difference in the speed of sound between the liquid and the medium from which it originated. This phenomenon is called Snell’s law, which states that the ratio of the sine of the angle of incidence to the sine of the angle of refraction is equal to the ratio of the velocities of sound in the two media.

Refraction and reflection of sound waves

When a sound wave encounters an obstacle in a liquid, such as a wall or other object, it is reflected back in the same direction from which it came. This phenomenon is known as reflection. Reflection of sound waves can also occur when a sound wave encounters a boundary between two liquids with different densities. In this case, some of the sound energy is reflected back while the rest is refracted into the other liquid.

How temperature affects sound wave propagation

Temperature also plays a role in the behavior of sound waves in liquids. As the temperature increases, the speed of sound in a liquid decreases. This means that sound waves will travel more slowly in hotter liquids than in colder ones. Additionally, high temperatures can cause sound waves to become distorted, resulting in a loss of clarity and fidelity.

How Does Sound Move Through Water?

Water is one of the most common liquids through which sound waves can travel. The speed of sound in water is approximately 1,500 meters per second (4,900 feet per second). This is about four times faster than the speed of sound in air.

Speed of sound in water

The speed of sound in water can vary depending on several factors, including temperature, salinity, and depth. Generally, the speed of sound in water increases as the temperature decreases and as the salinity increases. The speed of sound also decreases with increasing depth.

Factors that affect speed of sound in water

In addition to temperature and salinity, several other factors can affect the speed of sound in water. These include the density of the water, the viscosity of the water, and the pressure of the water. As the density of the water increases, the speed of sound also increases. Similarly, as the viscosity of the water increases, the speed of sound decreases. Lastly, as the pressure of the water increases, the speed of sound also increases.

Investigating the Factors that Affect Sound Propagation in Water

The speed of sound in water is affected by several factors. In order to better understand how these factors influence sound propagation, it is important to investigate each factor individually.

Density of liquid

The density of a liquid affects the speed of sound in the liquid. As the density of a liquid increases, the speed of sound also increases. This is because the molecules of a dense liquid are closer together, allowing sound waves to propagate through the liquid more quickly.

Viscosity of liquid

The viscosity of a liquid affects the speed of sound in the liquid. As the viscosity of a liquid increases, the speed of sound decreases. This is because viscous liquids have more resistance to the movement of sound waves, causing them to travel more slowly through the liquid.

The pressure of a liquid also affects the speed of sound in the liquid. As the pressure of a liquid increases, the speed of sound also increases. This is because higher pressure causes the molecules of the liquid to move faster, allowing sound waves to propagate through the liquid more quickly.

Acoustic Properties of Different Types of Liquids

The acoustic properties of a liquid can vary depending on its composition. For example, water has a different acoustic property than oil or alcohol. Each type of liquid has its own unique characteristics that affect the way sound waves behave in the liquid.

Characteristics of sound waves in different types of liquids

The characteristics of sound waves in different types of liquids can vary significantly. For example, sound waves in water tend to travel faster than sound waves in oil or alcohol. Additionally, sound waves in water tend to be clearer and less distorted than sound waves in other types of liquids.

Examples of different types of liquids

Some examples of common liquids that can be used to study sound wave behavior include water, oil, alcohol, and other fluids. Each of these liquids has its own unique properties that affect the way sound waves behave in the liquid. By studying these properties, scientists can gain a better understanding of how sound waves propagate through different types of liquids.

Utilizing Sound Waves to Measure Liquid Properties

Sound waves can be used to measure various properties of liquids, such as temperature, pressure, and depth. Scientists use sound waves to measure these properties by analyzing the way the sound waves reflect off of objects in the liquid. By measuring the amount of time it takes for the sound waves to travel from one point to another, scientists can determine the distance between the two points.

Use of sound waves in underwater acoustics

Sound waves can also be used in underwater acoustics to detect submerged objects and map out the ocean floor. By measuring the intensity of the sound waves, scientists can determine the size, shape, and location of an object. Additionally, sound waves can be used to detect changes in water temperature and salinity, which can be used to monitor ocean currents and climate change.

Applications of sound waves in measuring liquid properties

Sound waves can also be used to measure the properties of liquids, such as density, viscosity, and surface tension. These measurements can be used to monitor the quality of drinking water, analyze the chemistry of a liquid, and identify potential hazards in industrial settings.

Sound is a form of energy that can travel through liquids, such as water, oil, and alcohol. The behavior of sound waves in liquids depends on several factors, including the density and viscosity of the liquid, pressure, and temperature. Additionally, sound waves can be used to measure various properties of liquids, such as temperature, pressure, and depth. By understanding the physics of sound transmission in liquids, scientists can gain a better understanding of how sound propagates through different types of liquids and how to utilize sound waves to measure liquid properties.

(Note: Is this article not meeting your expectations? Do you have knowledge or insights to share? Unlock new opportunities and expand your reach by joining our authors team. Click Registration to join us and share your expertise with our readers.)

Hi, I'm Happy Sharer and I love sharing interesting and useful knowledge with others. I have a passion for learning and enjoy explaining complex concepts in a simple way.

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FREE K-12 standards-aligned STEM

curriculum for educators everywhere!

Find more at TeachEngineering.org .

• TeachEngineering
• Traveling Sound

Hands-on Activity Traveling Sound

Grade Level: 4 (3-5)

Time Required: 30 minutes

Expendable Cost/Group: US $2.00

Group Size: 2

Activity Dependency: None

Subject Areas: Physical Science, Reasoning and Proof, Science and Technology

NGSS Performance Expectations:

Curriculum in this Unit Units serve as guides to a particular content or subject area. Nested under units are lessons (in purple) and hands-on activities (in blue). Note that not all lessons and activities will exist under a unit, and instead may exist as "standalone" curriculum.

• Seeing and Feeling Sound Vibrations
• Pitch and Frequency
• Sound Visualization Stations

TE Newsletter

Engineering connection, learning objectives, materials list, worksheets and attachments, more curriculum like this, pre-req knowledge, introduction/motivation, vocabulary/definitions, troubleshooting tips, activity extensions, activity scaling, user comments & tips.

Sound and acoustic engineers know that the shape of a room and its materials greatly impact how sound waves travel. Recording studios are designed in soundproof booths so that the recorded music does not contain any unwanted external noise. Libraries are designed to reduce any introduced noises, to assure a quiet, non-distracting learning environment. Concert halls are designed so that sound generated on the stage travels to the back of the space without being distorted.

After this activity, students should be able to:

• Explain that sound can move through solids, liquids and gases.
• Describe how sound needs molecules to move and that changing the medium that it travels through changes the sound.
• Describe how engineers use sound energy when designing spaces, such as movie theaters.

Educational Standards Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards. All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN) , a project of D2L (www.achievementstandards.org). In the ASN, standards are hierarchically structured: first by source; e.g. , by state; within source by type; e.g. , science or mathematics; within type by subtype, then by grade, etc .

Ngss: next generation science standards - science, international technology and engineering educators association - technology.

View aligned curriculum

Do you agree with this alignment? Thanks for your feedback!

State Standards

Colorado - science.

Each group needs:

• large bowl (metal works best)
• 2 metal objects, such as spoons, to knock together
• Traveling Sound Worksheet , one per student

A basic understanding of the phases of matter: liquids, solids and gases.

Sound engineers are especially interested in the way sound travels. Can you hear as well when you sit in the back of the class as when you sit in the front? What about in the assembly hall or gymnasium? On the playground? Can you think of other times when you cannot hear as well as someone else? What happened? How about in a movie theater? What do engineers do so that the sound quality is good for everyone in a movie theater? (Possible answers: Add speakers around the room, curtains, carpet the walls, cone-shaped theaters act like a megaphone and help to direct sound waves further.)

Which is louder—walking on carpet or on tile? It is quieter on carpet because the carpet absorbs the sound energy . Sound energy, light energy and other types of energy, need molecules to travel through and vibrate , but sometimes sound energy is absorbed by an object or material. Engineers use this idea when designing rooms that are meant to be quiet. Have you ever noticed how the walls of a movie theater are covered with carpet or fabric? This is to prevent echoing of the sound system. Sometimes when you are in an empty room, your voice echoes or sounds hollow. This is because an empty room has no materials in it that might absorb the sound energy, so the sound bounces off the hard walls, back at you. This makes it hard to hear clearly.

Do you think sound energy can travel through air? Of course it can! That is how sound energy travels when you talk to a friend. How about water? Can you hear sound travel under water? How about a solid? Can sound move through a solid object? Engineers want to know if sound can travel through solids, liquids and gases so they can develop ways to send messages to people all over the world. Can you imagine how great sound would be if it could travel anywhere?

Understanding the properties of sound and how sound waves travel helps engineers determine the best room shape and construction materials when designing libraries, classrooms, sound recording studios, concert halls and theatres. Room shape and materials can impact how sound waves travel since sound waves bounce off different object in different ways. In this activity, we are going to study how sound waves travel through liquids, solids and gases, and think about how engineers might use this information.

Before the Activity

• Gather materials and make copies of the Traveling Sound Worksheet .
• Divide the class into teams of two students each.

With the Students

• Ask the students to predict if sound can move through solids, liquids and gases.
• Have the students complete the worksheet, which leads them through traveling sound wave activities.
• Can sound energy travel through solids? Students place their ears on a desk or table as they tap or scratch on the top. They compare that to the same sound made when their ear is not pressed to the table.
• Can sound energy traveling through liquids? Fill a large bowl or bucket (metal works best) with water. One student taps two spoons together under the water. Two other students observe and compare the tapping sound they hear, as heard through the air and as heard by placing an ear against the bowl.
• Can sound energy traveling through gases (air)? The students feel their throats gently during each of these tasks:
• Hum with your mouth and nose open.
• Hum with your mouth open and nose closed.
• Hum with your mouth closed and nose open.
• Hum with your mouth and nose closed.
• Discuss with the students what happened. Were their predictions correct? Can sound travel through air, water and solids? (Answer: Yes!) Sound needs molecules to move. Solids, liquids and gases are all made of molecules. The characteristics of the molecules (for example, the space between the molecules) determine whether the sound becomes muffled or changes in some way.
• How might engineers use the knowledge that sound travels through solids, liquids and gases? (Possible answers: Engineers create devices that send sound anywhere — through water to a submarine in the ocean, through wires to your TV, and through the air in surround sound movie theaters or emergency broadcast signals.)

echo: Repetition of a sound by reflection of sound waves from a surface.

frequency: The rate of vibrations in different pitches.

pitch: The highness or lowness of a sound.

sound energy: Audible energy that is released when you talk, play musical instruments or slam a door.

sound wave: A longitudinal pressure wave of audible or inaudible sound.

vibration: When something moves back and forth, it is said to vibrate. Sound is made by vibrations that are usually too fast to see.

volume: When sound becomes louder or softer.

wave: A disturbance that travels through a medium, such as air or water.

Pre-Activity Assessment

Prediction: Ask students if they think sound can move through solid, liquid, and gas. If so what are some examples? (Possible examples: Students may recall talking under water or using tin can and string telephones.)

Activity Embedded Assessment

Worksheet: Have students use the Traveling Sounds Worksheet to guide them in the activity and as a place to record their observations. Review their answers to gauge their mastery of the subject.

Post-Activity Assessment

Toss-a-Question:  Ask students to independently think of an answer to the question below and write it on a half sheet of paper. Have students wad up and toss the paper to another team member who then adds their answer idea. After all students have written down ideas, have them toss the paper wad to another team, who reads the answers aloud to the class. Discuss answers with the class.

• What is an example of something through which sound can travel?

Neighbor Check: Have the students compare their activity observations with a neighbor. Are they the same or different? Have each team report some of their similar and dissimilar observations to the rest of the class.

Engineering Design: The supply of air on Earth is running out! Several futuristic cities for human habitation are being designed either underwater or deep inside mountains. Have each student group become a city planning engineering team and draw a communication system for sending emergency messages between the new cities. Make sure to illustrate and describe how the sound energy (message) will move through air, water or solid rock.

This activity can be very loud. Ask students to not disturb others while they learn and have fun.

To bring some humor to the activity, ask each student to hum a small part of their favorite song while feeling their throat. Have each student alternate between having their nose and mouth open or closed while humming non-stop. Why does the sound change depending on whether you close your nose or mouth? What happens if you block your ears? What does this activity teach us about sound? (Answer: Sound vibrations must travel through air for us to hear them. Like a musical instrument [perhaps a recorder or flute], if you change the holes where sound escapes, it changes the pitch, but not the frequency/vibrations of the sound.)

If a metal bowl is used during the activity, the vibrations from the objects colliding underwater vibrate the bowl, creating the illusion that the bowl is being struck. Have students draw the vibrations in the bowl on a piece of paper. Do the vibrations change if the objects are tapped together increasing softly?

Have students think about different forms of communications. Does sound travel most often through solids, liquids or gases? Have students poll their friends, family and neighbors to solicit their ideas.

For lower grades, conduct the activities as a class instead of in teams. Younger students could also draw pictures of their observations instead of writing in sentence form.

Students are introduced to the sound environment as an important aspect of a room or building. Several examples of acoustical engineering design for varied environments are presented.

Students learn how different materials reflect and absorb sound.

Students learn that sound is energy and has the ability to do work. Students discover that sound is produced by a vibration and they observe soundwaves and how they travel through mediums. They understand that sound can be absorbed, reflected or transmitted.

Students use the engineering design process to design and create soundproof rooms that use only one type of material. They learn and explore about how these different materials react to sound by absorbing or reflecting sound and then test their theories using a box as a proxy for a soundproof room. ...

Dictionary.com. Lexico Publishing Group, LLC. Accessed December 19, 2005. (Source of some vocabulary definitions, with some adaptation.) http://www.dictionary.com

Contributors

Supporting program, acknowledgements.

The contents of this digital library curriculum were developed under grants from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation (GK-12 grant no. 0338326). However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: March 17, 2021

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Live updates: Iranian barrage of missiles and drones causes little damage, Israel says

What we know

• Iran launched more than 300 cruise and ballistic missiles and drones at Israel, IDF officials said, a retaliatory attack weeks after an Israeli strike on the Iranian consular building in Syria killed two of Tehran’s top commanders.
• There were explosions visible in the air over Jerusalem as air sirens rang throughout the country.
• The U.S. and Israeli militaries shot down the “vast majority” of the missiles and dozens of attack drones. Some missiles struck a military base in the south, causing minor damage.
• A 10-year-old girl was severely injured by shrapnel, and about 31 people were treated for anxiety or injuries they sustained while heading to a protected area when sirens sounded.
• Iran said that after tonight's attack, the "matter can be deemed concluded" unless there is more violence.

Israel reopens its airspace

Paul Goldman

Richie Duchon

The airspace over Israel was reopened at 7:30 a.m. local time Sunday, a spokesperson for Israel's airport authority said in a statement.

Flights out of Tel Aviv were likely to change, and travelers should check with airlines and on the airport authority's website for updates to flight schedules.

Domestic airports would remain open throughout the day, the statement said.

Iran launched over 300 projectiles, Israeli military says

Rudy Chinchilla

Israel intercepted 99% of the more than 300 projectiles launched by Iran, and is ready for “any further developments and scenarios,” Israel Armed Forces spokesman Daniel Hagari said.

Among the projectiles were some 30 cruise missiles, none of which made it into Israel, Hagari said. Only “few” of the more than 120 ballistic missiles launched entered Israel, with the rest being intercepted, he added.

Some of the ballistic missiles hit the Nevatim airbase, but they caused only minor infrastructure damage, and the base remained operational, Hagari said.

Iraq and Yemen also carried out launches against Israel, but none made it into the country, the IDF spokesman said. He added that “dozens” of rockets were launched from Lebanon toward the north of Israel, though Israel suffered no injuries or deaths and hit back by striking different targets in Lebanon.

A 10-year-old girl was severely injured by shrapnel, but there were no immediate reports of other Israeli injuries or deaths, Hagari said.

“Iran did something very serious, very severe this night, as it pushed the Middle East toward escalation. We will do whatever is necessary in order to defend the citizens of the state of Israel,” he said.

Netanyahu issues first public statement

Israeli Prime Minister Benjamin Netanyahu issued his first public comments since Iran's overnight attack, saying in a post on X, "We intercepted, we stopped. Together we will win."

U.S. destroyed 'dozens' of missiles and drones launched by Iran

Mosheh Gains

The U.S. military shot down "dozens" of missiles and drones en route to Israel, part of an "unprecedented" attack by Iran, Defense Secretary Lloyd Austin said in a statement late Saturday.

The aerial attacks by Iran were launched from Iran, Iraq, Syria and Yemen, he said.

"We condemn these reckless and unprecedented attacks by Iran and its proxies, and we call on Iran to immediately halt any further attacks, including from its proxy forces, and to deescalate tensions," Austin said in the statement. "We do not seek conflict with Iran, but we will not hesitate to act to protect our forces and support the defense of Israel."

Biden says he will coordinate a 'united diplomatic response' to Iran with G7 leaders

Doha Madani

President Joe Biden said he spoke with Israeli Prime Minister Benjamin Netanyahu tonight, reaffirming the United States’ commitment to the security of Israel.

Military forces followed Biden's direction to help Israel take down nearly all of the incoming drones and missiles, the president said. He also praised the country's ability to fend off attacks as a sign to others who threaten the security of Israel.

"Tomorrow, I will convene my fellow G7 leaders to coordinate a united diplomatic response to Iran’s brazen attack," Biden said. "My team will engage with their counterparts across the region. And we will stay in close touch with Israel’s leaders."

Though no U.S. forces have been attacked, Biden said America will "remain vigilant to all threats." He condemned the Iranian regime's attack tonight in the "strongest possible terms."

U.N. Secretary General condemns Iranian attacks

António Guterres, United Nations secretary-general, condemned the Iranian attacks on Israel tonight in a statement expressing concern over the serious escalation in the Middle East.

"I am deeply alarmed about the very real danger of a devastating region-wide escalation," Guterres said. "I urge all parties to exercise maximum restraint to avoid any action that could lead to major military confrontations on multiple fronts in the Middle East."

Guterres also condemned the April 1 attack on Iran's diplomatic premises in Damascus the day after it occurred.

He did not name Israel in that statement, which has not taken responsibility for the strike. Guterres emphasized the protection of diplomatic buildings and urged "all parties to respect all their obligations under international law."

U.N. Security Council to meet tomorrow

Rebecca Cohen

Yasmeen Persaud

The United Nations Security Council will meet Sunday following a request to hold an emergency meeting from Israel’s ambassador to the U.N.

The ambassador, Gilad Erdan, asked the council to condemn Iran's attack on his country and to designate the Iranian Revolutionary Guard Corps as a terror organization.

"The Iranian attack is a serious threat to global peace and security and I expect the Council to use every means to take concrete action against Iran," Erdan said in a post on X, which included the letter.

The meeting will take place at 4. p.m. ET, according to a U.N. schedule released tonight.

Iranian regime exercised 'its inherent right of self-defense' following diplomatic strike, foreign ministry says

The Iranian foreign ministry released a statement tonight reiterating its position that the strikes carried out against Israel were "in exercise of its inherent right of self-defense."

“The Islamic Republic of Iran would not hesitate to take further necessary defensive measures to protect its legitimate interests against any act of military aggression or unlawful use of force,” the statement said.

The ministry cited Article 51 of the United Nations charter and said that it was responded to Israeli's "recurring military aggressions," including the strike of Iran's diplomatic building in Syria earlier this mont.

The statement went on to say that its response was a "responsible approach" amid Israel's "apartheid" against Palestinians and "military aggressions" against neighboring states.

U.S. concerned Israel will respond to Iran without thought to potential fallout

Courtney Kube

Carol E. Lee Carol E. Lee is the Washington managing editor.

Some top U.S. officials are concerned Israel could do something quickly in response to Iran’s attacks without thinking through potential fallout afterward, according to a senior administration official and a senior defense official.

Those concerns stem in part from the administration’s views of the approach Israel has taken to its war against Hamas, as well as the attack in Damascus. 

President Joe Biden has privately expressed concern that Israeli Prime Minister Benjamin Netanyahu is trying to drag the U.S. more deeply into a broader conflict, according to three people familiar with his comments. 

The White House believes Israelis are not looking for a wider war or a direct war with Iran, but U.S. officials can’t be certain, the senior administration official said.

U.S. officials have privately expressed frustration with Israel’s decision to strike the Iranian consular building in Syria.

“I don’t think they had a strategy,” the senior administration official said. “The Israelis don’t always make the best strategic decisions.”

Senior leaders at the Pentagon also have privately expressed frustration at the timing of the Damascus strike, according to the senior defense official, because it had the potential to be “catastrophically escalatory.”

Netanyahu and Biden speaking

Yarden Segev

Prime Minister Benjamin Netanyahu is currently talking with President Joe Biden, according to a spokesperson for Netanyahu.

Their conversation follows discussions by the political-security cabinet and the war management cabinet, the spokesperson said.

Netanyahu's office did not disclose what the leaders discussed.

Israeli in Tel Aviv describes fighter jet sonic booms and explosions

Anna Schecter

Barak Herscowitz is hunkering down at home in Tel Aviv listening to what sounds him like a major war.

"The only sounds you hear, in a city where you would usually hear music from a nearby bar, is of fighter jets and explosions- no other sound," Herscowitz said.

Herscowitz, 38, said he is not in his safe room yet, and is feeling grateful for Israel's missile defense technology.

Hercowitz was just 7 years old when the Persian Gulf war broke out.

"I remembered today how we didn’t really have many ways to defend ourselves from both threats of that time: massive conventional missiles with mass destruction potential, and chemical weapons," he said. "This time, we have very strong air defense, almost all of the citizens have shelters in their homes — so for me, the feeling is much safer."

His real fear is for the long term: "This escalation is worrying mostly because it is unclear if Iran is dragging us to a much wider, longer and harder war on all fronts.” 

Hercowitz said he feels Israelis are resilient following more than six months of rocket fire from Iranian proxies.

"Although tonight is filled with an anxiety and I believe that no Israeli will sleep soundly, I’m optimistic we will get through these days in piece and the air defense will continue to work," he said.

Israeli security services say it treated 31 people

Israeli emergency services have been dispatched to treat 31 people who suffered from anxiety or minor injuries after emergency sirens blared throughout the country.

A statement from Magan David Adom noted that the injuries were caused "on their way to the protected area." It said it "continues to be on high alert."

A 7-year-old girl from the Bedouin diaspora was also in serious condition, but the cause of her injury is being investigated by police.

McConnell calls on House to pass national security supplemental amid Iran's barrage

Julie Tsirkin

Carly Roman

Senate Minority Leader Mitch McConnell called out the Republican-controlled House's inaction on a Senate-passed aid package for Israel and Ukraine after Iran launched an aerial attack against Israel tonight.

“Congress must also do its part," McConnell, a Kentucky Republican, said.

"The national security supplemental that has waited months for action will provide critical resources to Israel and our own military forces in the region. It will provide overdue lethal assistance to Ukraine and equip vulnerable allies and partners in Asia to deter the PRC. And it will make urgent investments in our own defense industrial base," he continued.

McConnell also urged President Joe Biden and Congress to "discharge our fundamental duties without delay." He did not elaborate on which duties he was referencing.

Biden has repeatedly said he will defend Israel against Iran and the U.S. is shooting down some drones flying toward Israel.

Richard Engel NBC News Chief Foreign Correspondent, Host of MSNBC's "On Assignment with Richard Engel"

JERUSALEM — Israel and Iran have been at odds for decades, but what we're seeing tonight is different. Iran is directly attacking Israel, instead of hiding behind proxies or using another militant group to attack Israel, therefore, inviting Israel to retaliate directly on Iranian territory.

It's important that Iran said that after this attack, it wants the conflict to be over, but to be determined is whether Israel, and Prime Minister Benjamin Netanyahu, agrees with that.

The drone attacks in Israel were the first wave of what Iran has said would be a three-wave attack. The second wave is comprised of more drones and missiles, and the third wave is ballistic missiles, which has the biggest potential to escalate this conflict into a regional war between Iran and Israel.

Many of Iran's strikes appear to be focused in southern Israel, in the Negev Desert area, where drones and missiles appear to have gotten through the air defense system.

Israeli media reported that some of the drones appeared to target the Knesset building in Jerusalem.

Biden's Situation Room meeting concludes

Kelly O'Donnell

Elyse Perlmutter-Gumbiner

President Joe Biden’s meeting with principals of the National Security Council in the White House Situation Room has concluded, per a senior administration official. It was roughly two hours long.

200 drones, missiles fired toward Israel: IDF

Over 200 different kinds of missiles and drones — including killer drones, ballistic missiles and cruise missiles — have been fired toward Israel in the Iranian attack that launched just hours ago, Israel Defense Forces spokesperson Rear Adm. Daniel Hagari said.

He called the attack a "wide scale escalation" and said the IDF is operating at "full force" to protect the people of Israel.

Hagari said the vast majority of drones and missiles have been intercepted outside of Israel’s borders with the help from Israeli allies. The U.S. said it has intercepted a number of drones.

A number of missiles were dropped inside Israeli territory, causing damage to a military base, Hagari said, adding that there were no reported casualties beside a girl who was hurt. He added, "we hope she will be well."

"We are ready for any threat that will come to Israel, we will do everything we need, everything, to defend the state of Israel," Hagari said.

U.S. politicians weigh in on Iran attack against Israel

After Iran launched hundreds of drones in an attack on Israel, House Speaker Mike Johnson said, “America must show our full resolve to stand with our critical ally."

Johnson, R-La., said Israel is not alone and assured he will work with the White House "to insist on a proper response."

He also called out the Biden administration, placing some blame on it for the attack.

"The Biden administration’s undermining of Israel and appeasement of Iran have contributed to these terrible developments," Johnson said.

Other politicians reiterated Israel's right to defend itself against such an attack and pledged U.S. support.

Sen. Roger Wicker, R-Miss., the top Republican on the Senate Armed Services Committee, said the U.S. commitment to Israel is “unwavering.”

“ This is the moment for the United States to show we stand together with our allies,” the senator said. “Our shared enemies, including Iran and their proxies, need to know our commitment is unwavering.”

Sen. Ben Cardin, D-Md., chairman of the Senate Foreign Relations committee, said in a statement to NBC News that “Israel has an inherent right to defend itself against these attacks from Iran and its proxies — before, during, and after they occur.”

Cardin, somewhat opposing Johnson's stance, said he supports President Joe Biden’s “iron-clad commitment to Israel’s security” and thanked his administration for taking what he said were necessary steps in recent days to support Israel as it prepared for an attack from Iran.

He reiterated that “the United States will continue to stand with Israel" and cautioned "Iranian regime leaders to not widen this already ill-conceived attack. Such escalation, especially targeting U.S. personnel and assets, should be dealt with swiftly and decisively.”

Others warned the attack could be far more extensive than it was initially thought to be.

Sen. Marco Rubio, R-Fla., the top Republican on the Senate Intelligence Committee, said on X , “The attack on #Israel by the regime in Iran is going to be more extensive than initially expected.”

So far, the U.S. has intercepted some drones launched at Israel and is working to do the same for incoming missiles.

Trump sounds off on Iran attack

Former President Donald Trump sounded off on the Iran attack on Israel at a rally in Pennsylvania tonight.

He told the crowd the attack was a product of American weakness.

"That's because we show great weakness," he told the crowd at the Schnecksville Fire Company fairgrounds. "This would not happen. The weakness that we've shown, it's unbelievable and it would not have happened if we were in office."

Trump added that "America prays for Israel" as Iranian missiles were fired toward the country.

Later on, members of the crowd could be heard chanting, "Genocide Joe! Genocide Joe!" to which Trump responded, "They're not wrong."

President Joe Biden has repeatedly said he will defend Israel against Iran and the U.S. is shooting down some drones flying toward Israel.

But his defense of the Jewish State has attracted criticism from some corners of his party, even pointing out on one occasion that some protesters who were chanting that he was “complicit in genocide” in Gaza "have a point.”

Rockets and flares burst across sky above Jerusalem

JERUSALEM — Israel's air defense systems appeared to be fully engaged in the early morning hours here. The dark skies above the Old City of Jerusalem intermittently lit up with orange flares as Israeli rockets appeared to be taking out incoming Iranian drones.

U.K. moves resources to Middle East to ‘encourage de-escalation’ of attacks

Andrew Jones

The U.K. is moving Royal Air Force jets and air refueling tankers to the Middle East "to encourage de-escalation and prevent further attacks," the Ministry of Defense said in a statement.

The statement said the jets from the U.K. will intercept airborne attacks near existing missions by the country.

"We will continue to cooperate closely with our regional partners in the interest of de-escalation," the ministry statement said.

Biden meets with national security team

President Joe Biden said in a post on X this evening that he met with his national security team to discuss Iran's attack against Israel.

Biden cut short a trip to Delaware to return to the White House today.

Rocket fire streaks across sky as air-raid sirens blare in Jerusalem

Daniel Arkin

JERUSALEM — The dark sky above the Old City of Jerusalem lit up tonight with orange flashes of rocket fire as air-raid sirens rung out across the city.

The bursts of rocket fire resembled shooting stars and appeared to come from Israel's sophisticated air defense system, not the Iranian drone attacks.

Iran fired missiles at Israel, U.S. official says

A U.S. official confirmed that Iran fired missiles at Israel and that the U.S. military is trying to shoot down Iranian missiles and drones bound for Israel.

The U.S. has shot down several Iranian drones but does not have confirmation that it has successfully shot down missiles. 

House schedule to change next week in light of Iran's attack on Israel

The House's schedule will change for next week, said Rep. Steve Scalise, the House Republican majority leader, and it will refocus on considering legislation to support Israel and hold Iran accountable.

"In light of Iran’s unjustified attack on Israel, the House will move from its previously announced legislative schedule next week to instead consider legislation that supports our ally Israel and holds Iran and its terrorist proxies accountable," Scalise said.

As Iran launches a retaliatory attack against Israel, former NBC News Tel Aviv bureau chief Martin Fletcher reports on how the Israeli air defense systems are prepared to stop certain attacks, but explains why the ballistic missiles may still break through.

Iran says attack in response to 'Zionist regime’s aggression' has concluded

Iran said it conducted a military attack on Israel "in response to the Zionist regime’s aggression against our diplomatic premises in Damascus," and that "the matter can be deemed concluded."

The Permanent Mission of the Islamic Republic of Iran to the U.N. said in a post on X that if Israel makes "another mistake, Iran's response will be considerably more severe," and that the matter is between Iran and Israel, and that the U.S. should stay out of it.

It said the attack was "legitimate defense" in response to the suspected Israeli attack on the Iranian consular building in Syria and was "conducted on the strength of Article 51 of the UN Charter."

The drones, launched hours ago, are beginning to arrive in Israel.

Sirens sound throughout Israel

Raf Sanchez

Yael Factor

TEL AVIV, Israel — Sirens have sounded across Israel — in southern and northern Israel, and the areas of Shomron, the Dead Sea and Jerusalem, the IDF confirmed.

The sirens all sounded in the span of about three minutes.

Residents of the northern Golan Heights, as well as the areas of Nevatim, Dimona and Eilat, have been told by the Israel Defense Forces they are required to stay near protective spaces until further notice.

The IDF said residents are required to enter a protected space when sirens are activated. If there is no protected space, residents must find the most protected area possible and wait 10 minutes, it said.

U.S. military has shot down Iranian drones

The U.S. military has shot down some Iranian drones tonight, according to U.S. officials.

The military intends to shoot down Iranian drones and missiles when they come into range of U.S. assets in Iraq, Syria and at sea.

The U.S. has beefed up its air defenses in recent months since the attack on Tower 22 and has repositioned assets in the region to be ready for this Iranian attack.

NYPD says no credible threats to city

Matt Johnson

Iranian attack is 'severe and dangerous escalation': IDF spokesperson

Jay Marques

Iran launching drones toward Israel "is a severe and dangerous escalation," IDF spokesperson Daniel Hagari said in an English video announcement.

Hagari said the IDF is "closely monitoring Iranian killer drones that are en route to Israel sent by Iran."

"Our defensive and offensive capabilities are at the highest level of readiness ahead of this large-scale attack from Iran," Hagari continued. "Together with our partners, the Israel Defense Forces is operating at full-force to defend the state of Israel and the people of Israel."

He said, "This is a mission that we are determined and ready to fulfill."

Biden to meet Iraq's prime minister on Monday

Dennis Romero

President Biden is expected to meet with Iraq's prime minister, Mohammed Shia al Sudani, on Monday in Washington in a face-to-face discussion that has been on the president's schedule for weeks.

Their topic of discussion pertains the scope of U.S.-Iraq relations, including military presence and trade.

According to the D.C.-based military think tank Institute for the Study of War , the Islamic Resistance in Iraq could resume attacks after a monthslong pause.

The militia, including other Iran-backed groups, want the United States to leave Iraq, and the meeting could produce a crucial moment during which anti-Western forces decide whether the goal of U.S. troop withdrawal has any traction, the institute said in a critical threats update on Friday.

The think tank cites remarks by Qais Khazali, secretary general of an Iran-backed militant group, Asaib Ahl al Haq, who is said to have warned of renewed attacks if the Biden meeting doesn't result in a U.S. troop withdrawal.

Those attacks on U.S. forces in Iraq were paused in February amid talks between Washington and Baghdad on the size and shape of the United States' presence in Iraq. The wider array of Iran-backed militias in the region, the Iran-named "Axis of Resistance," rejects any plan that includes a U.S. military presence in Iraq.

At the same time, Iraq's Al Sudani has proposed deeper economic, agricultural, industrial, technological and energy ties to the United States.

A group of GOP lawmakers is decrying the Biden-Al Sudani meeting, saying in a letter last month it represents "appeasement of Iran," given the country's influence in Iraq.

Sen. Chuck Schumer said the U.S. stands with Israel

"As Israel is under attack from Iran, we stand with Israel and its people, and the United States will do everything we can to support Israel’s defense against Iran," Senate Majority Leader Chuck Schumer, D-N.Y., said in a post on X .

Schumer is the highest-ranking Jewish official in the U.S.

He recently called for new elections in Israel to replace Prime Minister Benjamin Netanyahu.

Netanyahu convening war Cabinet

Israeli Prime Minister Benjamin Netanyahu is convening the war management Cabinet in Kirya in Tel Aviv, his office said.

Earlier today, before Iran launched hundreds of drones toward Israel, Netanyahu said the country has been preparing for the possibility of a direct attack from Iran in recent years and weeks.

"Our defense systems are deployed, we are prepared for any scenario, both in defense and attack," Netanyahu said. "The state of Israel is strong, the IDF is strong, the public is strong."

He said he appreciated the U.S. "standing by Israel's side," as well as Great Britain, France and "many other countries."

"I established a clear principle — whoever hurts us, we hurt him. We will protect ourselves from any threat and we will do so with coolness and determination," Netanyahu said. "Together we will stand, and with God’s help — together we will overcome all our enemies."

Biden back at the White House

Caroline Kenny

President Joe Biden arrived at the White House and was headed into the Oval Office at approximately 5:04 p.m. ET.

He is to meet with principals of the National Security Council to discuss the situation in the Middle East in the Situation Room, the White House said.

Biden cut short a trip in Rehoboth Beach, Delaware, where he was expected to spend the weekend.

X users circulate misleading videos amid Iran attack on Israel

Janhvi Bhojwani

When news broke that Iran had launched a retaliatory attack on Israel, some users on the social media platform X uploaded misleading videos, including footage from previous drone attacks or imagery from video games.

In one, an X user posted a video from six months ago showing Israel’s Iron Dome air defense system intercepting Hamas rockets in Ashkelon. In another post flagged by a reporter for the BBC, an X user falsely suggested that imagery from the video game “Arma 3” was video from today’s drone attacks.

Iran launches attack on Israel that risks sparking regional war

Dan De Luce

Aurora Almendral Aurora Almendral is a London-based editor with NBC News Digital.

Iran launched a retaliatory attack against Israel on Saturday that risks sparking a regional conflict that could draw in U.S. military forces. The attack marked the first time that Iran has launched a direct military attack on the Jewish state. 

Israeli military officials said the attack began with more than 100 Iranian drones heading toward Israel. It will take hours before the drones arrive, and Israeli officials said they hope to intercept them.

A senior Biden administration official warned that the assault could also involve dozens of cruise missiles and ballistic missiles. 

The official said the administration expects Israeli government facilities to be targeted but not civilian or religious sites. U.S. assets in the region are also not expected to be targeted, the official said.  

The U.S. and Israel have been closely coordinating how to defend against the attack, the official said. “We’re ready. The Israelis are ready.”

Read the full story here.

Israel has 'tens of aircraft' in Israel airspace: IDF

The Israeli Defense Forces have "tens of aircraft" in Israeli skies at the moment, an IDF official said at a briefing following Iran's launching of drones toward Israel.

The IDF confirmed the launching of drones but said it cannot confirm that Iran has launched any missiles. The official said the IDF cannot confirm the type or the payload of drones launched.

The official also said they cannot confirm if there have been any interceptions yet or what Iran is targeting in Israel.

The IDF is operating on "a pre-prepared action plan," the official said, adding that the idea is to intercept the drones before they reach Israel but that they will intercept the drones over Israel if necessary.

Congressional intelligence committees received classified info on Iran's plans

Members of the House and Senate intelligence committees had classified information made available to them last week on Iran’s plans to strike Israel, two congressional officials told NBC News.

The officials said they expect briefings from administration and intelligence community officials next week when Congress returns, but those briefings have not yet been scheduled.

Lebanese airspace is closed

Lebanese airspace has been closed to all arriving, departing and crossing aircraft, Ali Hamiyah, the minister of public works in the caretaker government, said in a post on X, in light of the attacks launched from Iranian territory toward Israel.

The closure is temporary, the government said, and will start at 1 a.m. local time and will be in effect until 7 a.m. local time.

Air traffic at Beirut Rafic Hariri International Airport will be completely closed during the same time period, according to the statement. Updates will be made according to developments in the situation.

U.K. Prime Minister Rishi Sunak condemns Iranian attack toward Israel

"I condemn in the strongest terms the Iranian regime’s reckless attack against Israel. These strikes risk inflaming tensions and destabilising the region," U.K. Prime Minister Rishi Sunak said in a statement.

"Iran has once again demonstrated that it is intent on sowing chaos in its own backyard," Sunak added.

Sunak said the U.K. will continue to "stand up for Israel’s security" as well as that of the U.K.'s regional partners, including Jordan and Iraq.

"Alongside our allies, we are urgently working to stabilise the situation and prevent further escalation. No one wants to see more bloodshed," Sunak said.

Israeli airspace closing to all domestic and international flights

Israel's airspace will be closed to all domestic and international flights starting at 12:30 a.m. local time, a spokesperson with the Israel airport authority said.

The spokesperson said the flight schedule from Tel Aviv is likely to change due to the delay in the arrival of flights to Israel and that the Ramon Airport will be closed to traffic.

Travelers should check with airlines and on the Airports Authority website regarding new flight times, according to the spokesperson, who said they will continue to provide updates as the situation develops.

El Al cancels 15 flights

El Al has canceled 15 flights, a spokesperson for the airline confirmed to NBC News. The canceled flights were mainly from Europe to Israel.

"In light of the closure of the airspace over Israel, some El Al flights are canceled," a statement from the airline said.

Updates will be posted on El Al's website and on social media. Customers whose flights were canceled will be notified when they can book an alternative when possible.

"El Al operates according to the instructions of the security forces and is in direct contact with them," the spokesperson said.

More than 100 UAVs launched toward Israel

More than 100 unmanned aerial vehicles were launched toward Israel, the IDF confirmed to NBC News.

U.S. bracing for 'major attack' in Israel

Now that Iran has begun its retaliation against Israel, the U.S. is bracing for this to be “a major attack,” according to two senior U.S. officials.

The administration’s expectation is Iran will launch more than 100 drones, dozens of cruise missiles and dozens of ballistic missiles targeting Israeli government sites, not civilians or religious sites, one of the officials said.

The U.S. and Israel have been closely coordinating on a defense against the attack. “We’re ready. The Israelis are ready,” the official said.

Commander of U.S. Central Command Gen. Michael “Erik” Kurilla was in Israel for a meeting with senior Israeli officials for the past several days, and now defense officials say he is traveling in the region. During his visit, Kurilla consulted with the Israelis on a defense plan that includes U.S. help from the sea and air, as well as how Israel might respond to Iran’s attack, the senior U.S. officials said.

The administration is not expecting Iran to target any U.S. assets in the region, the officials said.

IDF says Iran has launched attacks on Israel

Israeli Defense Forces spokesperson Hagari said in a televised statement in Israel today that "Iran launched unmanned aircrafts from its territory towards the territory of the State of Israel."

He reiterated that the threat will take "several hours" to reach Israel and that the IDF and the Israeli Air Force are implementing their plan that has been prepared for this moment.

He noted that if the threat is determined to arrive sooner than expected, updates will be provided.

In a separate statement, the IDF said Iran "launched UAVs from within its territory toward Israel," adding that the IDF, including the IDF Aerial Defense Array, is on "high alert and is constantly monitoring the operational situation," as are IAF fighter jets and Israeli Navy vessels.

The IDF is also monitoring all targets, it said. Hagari said they are also monitoring the threat in the airspace.

Hagari urged Israelis to be "vigilant" and to follow directives in accordance with the plans.

"We know these threats and have dealt with them in the past. If an alert is activated in the area where you are, you must enter the protected area and stay here for at least 10 minutes," Hagari said to the Israeli people. "We will update you if you are required to stay in the protected area for a longer time."

He said Israelis will be given updates and be notified of any changes in the situation from the IDF and the Home Front Command.

"Continue to behave responsibly and calmly, as you have done so far, be careful and act according to the instructions," Hagari said.

He added: "The IDF is prepared and ready for all its formations in defense and attack. We prepared for a variety of scenarios in advance. We work in close cooperation with the U.S. and our partners in the region to act against the launches and intercept them."

"But remember," Hagari warned, "the protection is never hermetic. That is why it is very important to follow the instructions and obey the instructions of the Home Front Command, they save lives."

Biden to meet with principals of the NSC on Iran attacks

President Biden will meet with principals of the National Security Council to discuss the situation in the Middle East in the White House Situation Room, the White House said.

Earlier today, Biden was briefed on the matter by national security adviser Jake Sullivan and principal deputy national security adviser Jon Finer, according to the White House.

They will later meet with Defense Secretary Lloyd Austin, Secretary of State Antony Blinken, Chairman of the Joint Chiefs of Staff Gen. Charles Q. Brown, CIA Director Bill Burns, Director of National Intelligence Avril Haines, counselor to the president Steve Ricchetti and National Security Council Coordinator for the Middle East and North Africa Brett McGurk.

Vice President Kamala Harris and chief of staff Jeff Zients will also attend the meeting virtually by secure video, the White House said.

The U.S. military is ready to help defend Israel in attacks from Iran that are expected to last for hours

Iran has begun its retaliatory strikes against Israel, according to three U.S. officials.

The attacks are beginning with drones, the officials said, but they expect Iran to launch missiles as part of what is expected to be an hourslong operation that is now expected to last late into the night.

The U.S. is prepared to help defend Israel with ships, including the USS Carney, a destroyer that has been involved in shooting down Houthi projectiles but is now repositioned to help Israel, as well as other destroyers and assets, the officials said.

NSC confirms 'airborne attacks on Israel'

Allie Raffa

NSC spokesperson Adrienne Watson confirmed in a statement that Iran has launched its “airborne attacks on Israel.”

President Joe Biden is being updated about the situation in the Middle East by his national security team and plans to meet with them this afternoon at the White House, the statement said.

Additionally, Biden's team is in "constant contact" with Israeli officials, partners and allies.

The attack on Israel is likely "to unfold over a number of hours," Watson said in the statement.

"President Biden has been clear: our support for Israel’s security is ironclad," the statement said. "The United States will stand with the people of Israel and support their defense against these threats from Iran."

Iran supreme leader had warned that Israel would be 'punished'

Earlier this week, Iran’s supreme leader,  Ayatollah Ali Khamenei , said at a prayer ceremony celebrating the end of the holy month of Ramadan that Israel “must be punished, and it will be punished.” His remarks were broadcast by Iranian state TV.

His comments came after Israel’s Foreign Minister Israel Katz said on X that his country “will respond and attack in Iran” if it attacked from within its territory.

Iran launches drones toward Israel

Iran has launched drones toward Israel, IDF spokesman Daniel Hagari said in a statement, in an attack that Tehran had promised to carry out after its embassy in Damascus was hit last week.

U.S. restricts travel for Israel staff as Iran attack fears rise

Yuliya Talmazan

The United States has restricted travel for its staff in  Israel , as fears grow of an imminent retaliatory attack by  Iran .

The U.S. Embassy in Jerusalem issued  a security alert Thursday  restricting its employees and their family members from personal travel outside the greater Tel Aviv, Jerusalem and Be’er Sheva areas until further notice “out of an abundance of caution.”

Israel threatened to strike Iran directly if it launches attack from its territory

The Associated Press

Israel’s foreign minister threatened Wednesday that his country’s forces would strike  Iran  directly if the Islamic Republic launched an attack from its territory against  Israel .

“If Iran attacks from its territory, Israel will respond and attack in Iran,” Israel Katz said in a post on X in Farsi and Hebrew.

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Iran missile and drone attack on Israel – what we know so far

Israel’s military has reported minor damage after Iran launched dozens of drones and missiles towards it late on Saturday

• Iran attack on Israel – live updates
• Full report: Iran launches drones and cruise missiles against Israel

Iran launched hundreds of drones as well as cruise missiles towards Israel , in the Islamic Republic’s first ever direct attack on the Jewish state in response to the 1 April strike on an Iranian diplomatic building in the Syrian capital of Damascus which killed a senior figure in Iran’s Islamic Revolutionary Guards, and eight other officers.

“Very little damage was caused,” according to Israel’s defence minister, Yoav Gallant. An IDF spokesperson said 99% of the more than 300 missiles and drones were intercepted. Sirens blared across the country and explosions were visible in the sky as the first wave reached Israel at around 2am local time (midnight BST) and Israeli air defence systems went to work.

Iranian strikes caused “minor damage” to the Nevatim airbase in the south of Israel , army spokesperson Daniel Hagari said Sunday. “Only a few missiles fell in the territory of the state of Israel with slight damage to a military base in the south, with only slight damage to the infrastructure,” Hagari said in a statement.

US secretary of defence, Lloyd Austin said that US forces intercepted “dozens of missiles and UAVs [unmanned aerial vehicles] en route to Israel,” while Gallant praised the assistance of the US and “additional partners”.

US president Joe Biden said Iran was aided by its proxy forces in Yemen, Syria and Iraq. He praised the work of US military personnel in helping to bring down “nearly all” of the drones and missiles fired by Iran. Biden cut short a weekend stay at his Delaware beach house to return to the White House to meet his national security team. He has said he will convened a meeting of G7 leaders on Sunday.

Royal Air Force fighter jets and refuelling aircraft were also involved, taking off from bases in Cyprus. Their role, according to the UK Ministry of Defence, was to fill in for the US air force in the sorties against the Islamic State normally carried out over Iraq and north-eastern Syria, but also to intercept Iranian drones if they came into the UK area of operations.

Reuters quoted two regional security sources as saying Jordanian jets had downed dozens of Iranian drones flying across northern and central Jordan heading towards Israel.

World leaders have condemned Iran’s attack with regional powers including Saudi Arabia and Egypt called for restraint. UN secretary general António Guterres said: “I am deeply alarmed about the very real danger of a devastating region-wide escalation. I urge all parties to exercise maximum restraint to avoid any action that could lead to major military confrontations on multiple fronts in the Middle East.”

The UN security council will hold an emergency meeting on Sunday, at the request of Israel’s ambassador to the UN, the council’s president said in a statement to media.

A growing chorus of US congressional leaders are calling for the supplemental aid bill to be passed, with US Senate majority leader Chuck Schumer saying it was the clearest way to help Israel. The $95bn supplemental spending bill includes $14bn for Israel, in addition to $60bn for Ukraine and support for Taiwan. It was passed by the Senate with 70% support in February but has been blocked in the House.

House majority leader Steve Scalise said in a statement on Saturday that there will be a change to the House schedule to consider legislation that supports Israel, but it was unclear whether Scalise was referring to a stand-alone bill to aid Israel or the $95bn supplemental spending bill.

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