Airport body scanners, specifically Advanced Imaging Technology (AIT) devices, use non-ionizing millimeter wave technology or very low-dose X-rays, generally considered safe for travelers.
Navigating airport security is a routine part of travel, and for many, the body scanner is a moment of hesitation. It’s natural to wonder about the technology used and its potential effects. Let’s break down the facts about these devices and what they mean for your health and travel plans.
Understanding Airport Body Scanners: The Basics
Airport body scanners, officially known as Advanced Imaging Technology (AIT) systems, are designed to detect metallic and non-metallic objects, including weapons, explosives, and other threats concealed under clothing. They are a primary method for passenger screening at security checkpoints. These systems provide a quick and efficient way to enhance aviation security, reducing the need for more intrusive physical searches in many cases. The goal is to ensure a safe journey for everyone on board.
Millimeter Wave vs. Backscatter Scanners: A Closer Look
There are two main types of AIT scanners, though one is far more common in US airports today.
Millimeter Wave Scanners
Millimeter wave scanners are the most prevalent type of body scanner found in US airports. They operate by emitting low-power radio waves, a form of non-ionizing electromagnetic radiation, which are reflected off the body. These waves do not penetrate the skin. The reflected signals create a generic, privacy-protective outline of a person’s body, highlighting any anomalies or concealed items. The image displayed to the security officer is a stick figure or avatar, not a detailed anatomical representation, safeguarding passenger privacy. This technology is similar to that used in cell phones and Wi-Fi devices.
Backscatter X-ray Scanners (Largely Phased Out)
Backscatter X-ray scanners use very low-dose X-rays to create an image. These devices were designed to detect objects by showing the density differences between the body and concealed items. While deemed safe by health agencies, concerns about privacy and the use of ionizing radiation, however minimal, led to their widespread replacement. According to the TSA, backscatter units have been phased out of primary screening at US airports and replaced with millimeter wave technology. This means you are highly unlikely to encounter a backscatter scanner at a US airport checkpoint today.
The Science of Safety: Radiation Exposure Explained
Understanding the science behind these scanners helps clarify their safety profile.
Non-Ionizing vs. Ionizing Radiation
The distinction between non-ionizing and ionizing radiation is key. Ionizing radiation, such as that from medical X-rays or CT scans, carries enough energy to remove electrons from atoms, which can potentially damage DNA. Millimeter wave scanners use non-ionizing radiation. This type of radiation does not have enough energy to cause atomic changes or DNA damage. Examples of non-ionizing radiation are radio waves, microwaves, and visible light. While backscatter scanners did use ionizing radiation, their doses were extremely low, comparable to a few minutes of cosmic radiation experienced during flight.
Expert Consensus on AIT Safety
Leading health and scientific organizations consistently affirm the safety of millimeter wave scanners. The U.S. Food and Drug Administration (FDA), which regulates medical devices and radiation-emitting products, has evaluated AIT systems. The FDA states that the energy levels used by millimeter wave scanners are well below international and national safety standards and do not pose a health risk. The radiation dose from these devices is negligible, far less than the natural background radiation people are exposed to daily, or the radiation received during a typical airplane flight at cruising altitude.
| Feature | Millimeter Wave (AIT) | Backscatter (Legacy) |
|---|---|---|
| Technology | Low-power radio waves | Very low-dose X-rays |
| Radiation Type | Non-ionizing | Ionizing (minimal dose) |
| Current Status in US | Primary technology used | Largely phased out |
| Image Output | Generic avatar/outline | Privacy-filtered image (more detailed) |
Specific Concerns and Special Circumstances
Certain travelers often have particular questions about body scanners. Here’s what to know.
Pregnancy and Children
For pregnant travelers, millimeter wave scanners are considered safe because they use non-ionizing radiation that does not penetrate the body. This means there is no known risk to the fetus. Similarly, children are also safely screened by these devices. The radiation exposure is minimal and non-ionizing, posing no greater risk than standing near other electronic devices. If a parent or guardian has concerns, they can always request an alternative screening method.
Medical Devices and Implants
Travelers with pacemakers, defibrillators, cochlear implants, insulin pumps, or other medical devices can generally pass through millimeter wave scanners without issue. The non-ionizing radio waves do not interfere with or damage these devices. It is always a good idea to inform the security officer about your medical device and carry any relevant medical ID cards. If you have any doubts or prefer, you can request a pat-down instead of a scan.
| Traveler Group | Scanner Recommendation | Alternative Option |
|---|---|---|
| Pregnant Travelers | Millimeter wave scanners are safe. | Request a pat-down. |
| Children | Millimeter wave scanners are safe. | Request a pat-down. |
| Medical Implants | Generally safe with millimeter wave. Inform officer. | Request a pat-down. |
| Ostomy Bags | Millimeter wave scanners are safe. Inform officer. | Request a pat-down and private screening. |
Your Rights and Options at the Checkpoint
Understanding your rights and available options can make your security experience smoother.
Every traveler has the right to decline an AIT body scan. If you choose not to go through the scanner, you will be offered an alternative screening method, which is typically a physical pat-down. This pat-down is conducted by a security officer of the same gender. You can request a private screening area for the pat-down, away from the main checkpoint area. Remember to communicate clearly with the security officers about your preferences and any medical conditions you have. Cooperation helps ensure a respectful and efficient process for everyone involved.
Traveler Tips for a Smooth Security Experience
A few simple practices can help you move through the security checkpoint with ease.
- Dress Smart: Avoid wearing excessive jewelry, belts with large buckles, or clothing with many metal embellishments that might trigger the scanner. Simple, comfortable clothing works best.
- Empty Pockets: Before approaching the scanner, ensure all items are removed from your pockets and placed in your carry-on bag or a bin. This includes keys, wallets, phones, and loose change.
- Listen to Instructions: Pay attention to the security officers’ directions. They will guide you on where to stand, how to position your arms, and when to exit the scanner.
- Communicate: If you have a medical condition, an implant, or simply prefer a pat-down, clearly and politely inform the officer before entering the scanner.
- Stay Calm: Security checkpoints can be busy, but maintaining a calm and patient attitude helps everyone.
Addressing Common Misconceptions
Several misunderstandings persist about airport body scanners, often causing unnecessary worry.
One common misconception is that the scanners produce a “naked” image of the traveler. Millimeter wave scanners generate a generic, privacy-protective outline or avatar. Any areas where an anomaly is detected are highlighted on this generic image, not a detailed anatomical view. Another concern is that the radiation exposure is significant. As established, the non-ionizing radiation from millimeter wave scanners is extremely low, comparable to ambient environmental radiation and far less than many other daily exposures or a single dental X-ray. These devices are designed with passenger safety and privacy as core considerations, balancing security needs with public health.