Airport scanners use a form of electromagnetic radiation to see through objects. Aluminum foil is effective at blocking this radiation, so it is likely that the scanner cannot see through it.
So you’ve heard the news: airport body scanners can see through clothing and even aluminum foil. They are also capable of detecting suspicious items concealed on your person, such as knives or explosive materials.
If you don’t trust the TSA with your personal safety, or you just happen to be a paranoid individual, it may seem like an ideal time to invest in some aluminum foil to protect yourself from those creepy see-through machines. But is this a good idea? Can the scanners see through aluminum foil? Are there any other methods that are better at thwarting intrusive security measures? Let’s find out!
What do Airport Scanners Look For?
Before we start talking about scanners, let’s get some misconceptions out of the way.
First, the scanners you see at the airport are actually very different from the type of scanners you see in a doctor’s office. Those machines use X-rays to image your body, while the airport scanners use electromagnetic waves on the same frequency as a microwave oven.
Second, the scanners are not primarily used to look for contraband. Instead, they are designed to detect objects on a person’s body that could be used to cause harm to others.
Some of the objects that scanners are designed to detect include:
- Hidden knives or other sharp objects.
- Explosives, such as those in belts.
- Guns and other firearms.
- Large, irregularly-shaped pieces of metal.
- Large, irregularly-shaped pieces of dense material, such as ceramics or stones.
Can airport scanners see through aluminum foil?
The short answer is yes. Anyone who has ever used a microwave knows that electromagnetic waves can go right through aluminum foil. In fact, other metals such as copper or iron are better at blocking these waves than aluminum. The electromagnetic waves used in airport scanners are extremely powerful and can penetrate obstructions that are up to 2mm thick. Aluminum foil, which is only 0.0007 inches thick, is not very effective at blocking these waves.
Is it possible to create an aluminum foil barrier?
If you were to fold several layers of aluminum foil together, you might be able to create a barrier that is thick enough to block the waves. However, there is no guarantee that the scanner would not be able to detect the metal, or that the barrier would be thick enough to trigger an alarm.
Plus, creating a barrier that thick would be impractical and uncomfortable. Additionally, you would also have to worry about hygiene and sanitation. Those aluminum layers would have to be thoroughly washed to prevent the spread of bacteria.
Can metals other than aluminum foil block airport scanners?
Yes, some other metals are better at blocking electromagnetic waves than aluminum. However, it would be very difficult to fashion them into a suitably thick barrier. Some examples of good metals to choose are iron, copper, or silver.
Iron is the best choice, since it does not tarnish, and is easy to find in the form of steel wool. However, it would be exceptionally difficult to create a thick enough barrier with metal. It would require a lot of fabricating and sewing, as well as shearing off the sharp edges of the iron.
Are there any devices that can be used to detect airport scanners?
As we have seen, the electromagnetic waves used in airport scanners are difficult to block. However, there are some devices that can be used to detect the scanners, albeit at a much greater distance than their effective range. Some examples are:
- Simple metal detectors: These can be used to detect large pieces of metal, but not dense or irregularly-shaped objects such as ceramic knives.
- Scintillation detectors: These can be used to detect any object that emits ionizing radiation. This includes metals, nuclear materials, and chemical explosives. The disadvantage is that they can detect the scanner itself, so they must be placed at a distance.
Putting all this information together, it seems the best way to protect yourself from airport scanners is to wear clothing that is both thick and dense. That way, any items you conceal on your person will have to be relatively large. We also recommend that you avoid bringing large amounts of high-contrast metals, such as coins or keys, with you to the airport.
If you are worried about the privacy implications of airport scanners, we suggest trying to avoid them as much as possible. If you absolutely must go through a scanner, try to do it when the airport is less busy, and choose a scanner that has a “random selection” button. Finally, if you’re really concerned about being scanned, you can try covering yourself in aluminum foil!