For every passenger to catch a flight, they and their luggage will need to go through a series of security measures, one of which is walking through an airport body scanner.

Airport body scanners are designed to detect threats to aviation security, so are designed to detect weapons and explosives a passenger might be attempting to sneak onto a plane.

But can airport body scanners see your naked body or inside you?

Can they detect tumors and medical problems?

Should you be worried about your privacy when walking through an airport body scanner?

Airport Body Scanners Can Detect Drugs

Airport body scanners can detect drugs, but only if they are on the person, such as inside a pocket of clothing, and not if they are hidden inside a body cavity.

TSA agents aren’t actually looking for drugs, but have a duty to report a passenger if drugs are found.

Don’t Worry. Airport Body Scanners See Your Naked Body

Early versions of airport body scanners used to be able to show your naked body, but this isn’t the case anymore.

These scanners used backscatter technology, but now millimeter wave machines are used instead.

Backscatter scanners can still be found in smaller airports and other countries.

Airport Body Scanners Can’t See Tampons Either

Airport body scanners are unable to see tampons or menstrual cups.

This is because the scanners are unable to penetrate the body, just clothes instead, and also do not provide an anatomically correct image either.

Airport Body Scanners Have Detected Tumors and Other Medical Problems

Airport body scanners can detect tumors and some other medical problems because they use radiofrequency waves to scan for abnormalities or bulges on passengers.

JAMA Dermatology, which is a peer-reviewed medical journal published by the American Medical Association, reports that one female passenger with a skin cyst was regularly stopped on suspicion of hiding an explosive device at a U.S. airports.

Another case involved a man with a protrusion in his groin area that set off airport scanners.

He was interrogated and subjected to a genital exam.

Airport body scanners are unable to detect cancer or inflammation, though.

Related: Can You Fly With a Pacemaker?

Airport Body Scanners Deliver Very, Very Little Radiation

According to the Health Physics Society, airport scanners deliver 0.1 microsieverts of radiation per scan.

If we compare this to a typical chest X-ray that delivers 100 microsieverts of radiation, we can confidently say that airport body scanners are completely safe, with the radiation a passenger is exposed to being negligible.

However, this only concerns backscatters scanners.

No long-term studies have been done on the health effects of millimeter wave scanners.

You May Be Able to Refuse to Go Through an Airport Body Scanner

In the U.S, according to TSA security screening procedures, you are legally allowed to refuse to go through an airport body scanner and will subject to a physical body search instead.

In other countries, such as the UK, if you refuse to go through an airport body scanner, you will not be allowed to pass through airport security and will not be able to fly.

Why You Always Seem to Set Off Airport Body Scanners

If you keep on setting off airport body scanners and are sure that you aren’t walking through the scanner with anything that might set it off, it’s a good idea to visit your doctor as soon as possible.

The scanner might be detecting a medical problem, or something harmless like lipomas (fatty lumps) or lipodystrophy (abnormal distribution of fat).

The scanner might also be detecting something you never would have thought of, like sequins or stitching on your underwear, or a fold in your clothes.

How Airport Body Scanners Work

Airport body scanners either use backscatter or millimeter wave technology.

Backscatter X-ray scanners work by hitting you with harmless ionizing radiation that reveal if you have any solid items on you.

Millimeter-wave scanners, which work by bouncing electromagnetic waves off you, construct 3-dimensional animated images of you that show everything you have on you.

Airport Body Scanner Privacy Concerns

Passengers quite rightly have privacy concerns when going through scanners at the airport.

Thankfully, in the U.S., Automatic Target Recognition (ATR) software is used, which only displays generic body outlines.

This has been standard since June 1, 2013, at all U.S. airports.

Software imaging technology can also mask specific body parts

Most airports have also now replaced their backscatter x-ray scanners with millimeter-wave ones because of privacy concerns, but some airports, especially smaller airports and those in other countries, still have them.

The TSA has claimed that any images captured are not stored. But the U.S. Marshals Service has admitted that it had previously saved thousands of images, which is concerning.

The Future of Airport Body Scanners

In the future, artificial intelligence may be used to improve security and make passengers lives easier.

The idea is for future airport body scanners to allow passengers to pass through while wearing coats and without removing items from pockets

Sequestim, which is a company that aims to commercialize the next generation of Terahertz Imaging Technology, are designing a walk-through scanner that uses the latest space technology.

The scanner will use Machine Deep Learning to distinguish threats from ordinary objects, will shine no radiation, and no-one will see the image.

Ella Dunham, a Freelance Travel Journalist and Marketing Manager, boasts an impressive career spanning eight years in the travel and tourism sectors.

Honored as one of "30 Under 30" by TTG Media (the world’s very first weekly travel trade newspaper), a "Tour Operator Travel Guru" and "Legend Award" winner, Ella is also a Fellow of the Institute of Travel, a Member of the Association of Women Travel Executives, has completed over 250 travel modules, and hosts travel-focused segments on national radio shows where she provides insights on travel regulations and destinations.

Ella has visited over 40 countries (with 10 more planned this year).