Can I Take Aluminum Foil Through Airport Security?

If you are packing for your holiday away or you are simply interested in how airport metal detectors work, you might be trying to figure out whether or not aluminium foil will set off an airport detector. 

So, to answer your question, yes, aluminium foil will set off a metal detector, even if it’s used in food wrappers or carried as sheets, this is because even though aluminium might not be magnetic, it is still a metal that has electrical conductivity, this means it will be triggered by a detector.

Aluminium foil however can be brought through security despite this, but might mean you have subject your luggage to some extra checks, we have gone into further detail below about airport alarms and surprising items that will set them off when you go travelling.

How Does an Aiport Metal Detector Work?

To understand why aluminium foil will set off airport security systems you should first get to grips with how these machines work and the types of metal that will set them off.

When making your passage through airport security to get to your gate, you will likely have to pass airport checkpoints and one of them will require you to walk through a detector machine, while the other machine will x-ray your luggage. 

The purpose of these active metal detectors is so as they can detect any dangerous items such as an airport explosive and other magnetic items/non-magnetic items which may be concealed to use as weapons. 

Airport metal detectors operate by using PI technology which uses pulses from two coils on the machine to create an electromagnetic field, these electrical pulses once ended will generate an electrical spike that will trigger a reflective pulse. 

When aluminium foil or a metal item is detected, this will make pulses last longer thus trigger the airport security alarm for a search.

What About An Airport X-ray Machine?

If you have any aluminium foil in your carry on luggage, then you should expect your luggage to be sent for the additional screening queue as this will show up as a dark shape on the machine, that’s why most of the time common items have to be put in clear plastic bags according to luggage rules.

Why Does Aluminum Foil Set Off Airport Security?

You are probably wondering why a foil wrapper from chewing gum or your wrapped peanut butter sandwiches would be a cause for concern by transportation security officers. 

This is because aluminium is metal and doesn’t allow the x-ray to see through it, causing for closer inspection so as the aluminium foil can be seen to not be concealing anything.

What Other Types Of Metal Are Detected?

Aluminium foil is not the only metal you want to keep out your carry on and pockets if you are wanting to avoid a search for suspicious metals. 

You should additionally prepare for a search if you are bringing through these metals at airports – 

• Gold. 
• Silver. 
• Brass. 
• Copper. 

Can I Bring Aluminum Foil Through Airport Security?

If for some reason you accidentally bring food in aluminium packagings such as peanut snacks or you take food from its original container and wrap it up in a tin foil, no matter what, the metal object will still most likely set off the alarm at the airport.

However, after some unwanted questioning, you will still be allowed to pass through with it, it just costs you time, which you don’t want before a flight.

Just like the requirements for liquids, it’s much easier to pack food in a one-quart sized, zip-top bag, this will allow you to have a smooth passage (as long as the food is allowed) and avoid an unneeded search.

Can Tin Foil Block Airport Security Metal Detectors?

Most detectors at an airport will not notice aluminium foil and see straight through it if you are concealing anything inside, despite rumours, these foils are not thick enough to block any detection, but can block x-ray machines in post offices. 

Even if tin foil may be able to block an item being seen by the x-ray, it will still show an unusually large blob which probably means a time-consuming cross-examination.

What Everyday Items Will Set Off Airport Security?

Now we know we should leave the peanut wrappers and foiled chewing gum at home, you might be curious to know about the other everyday items that can give you a hard time when travelling. 

• Your personal minibar – There is nothing wrong with bringing alcohol on the plane for your pre-holiday session but these liquid measurements must follow the 3-1-1 requirements which means the alcohol should be in one 3.4 ounce limit bottle, in its original container and with its in own plastic bag.
• Inhalers – Inhalers do unfortunately violate the ”3-1-1” rule, this means they have the potential to set off the alarm at airport security and interrupt the swift flow through the security, to avoid this becoming a big deal, notify the security beforehand and label the inhaler.
• Headbands – Headbands are often made with a metal frame so can set off the alarm, just put this along with valuable items in a tray to go through the x-ray beforehand.
• Metallic lingerie – Okay, well not metallic lingerie exactly but the metal wire on your clothing items can require you to have a search by a female agent, detectors, however, are less likely to be set off by this nowadays, just to make sure you could wear a sports bra instead.
• A tub of peanut butter – That’s right, peanut butter, we know it’s not a liquid, but security won’t like it due to the fact it takes the shape of its plastic containers just like cold cream and gel items, it’s better of packing this in your checked luggage.
• Metal buttons – Most detectors will require you to remove bulky clothing like jackets if they have metal buttons when you move through the detector as this can set the alarm off.

Frequently Asked Questions About Aluminum Foil & Airport Metal Detectors 

Can stainless steel set off an airport metal detector? 

Stainless steel is 60% made up of iron and is considered a ferrous metal even though many people class it as nonferrous metal, this makes it very hard to detect but still will be set off from airport detectors, these metals in nature are more suspicious to authorities too.

Why don’t metal zippers on jeans set off airport security alarms? 

Airport detectors will be able to filter out certain metals and set thresholds. Nowadays, most of them will be able to let people pass through with buttons and zippers on their jeans, but extra items such as jackets should be removed.

Will crystal balls be okay to take on a plane? 

If your crystal ball contains liquid like a snow globe the no, unfortunately not as TSA’s 3.4-ounce limit on rules for liquid will class this as excess.

Can Airport Metal Detectors Be Set Off by Non-Metal Objects Like Phones?

Yes, phones and airport metal detectors can sometimes set off false alarms. Airport metal detectors are typically calibrated to detect metal objects, but certain non-metal items like phones with metal components can also trigger the alarm. It’s important to follow airport security guidelines and be prepared to remove any items that may activate the metal detector.

Final Words 

To conclude, aluminium foil will set off airport metal detectors, so you should avoid bringing it through security unless you have to, always make sure to clear your pockets of foil wrappers to avoid being searched and follow TSA’s rules on food and liquid packaging. 

Always check the types of metal you allowed to bring through security beforehand and allow extra time for passing through security if you know you are bringing items that could potentially set off the alarm.