Are Airport Scanners Harmful? | Facts & Your Health

Airport scanners, including millimeter wave and backscatter X-ray systems, expose travelers to extremely low levels of radiation or radiofrequency energy, generally considered safe.

Navigating airport security is a routine part of travel, and while the process aims to keep everyone safe, it’s natural to wonder about the technology involved. Many travelers pause at the thought of stepping into a scanner, questioning what it means for their health. Understanding how these systems work can help demystify the experience.

Understanding Airport Security Scanners

When you step into an airport security checkpoint, you’ll typically encounter one of two primary types of advanced imaging technology (AIT) scanners. Both are designed to detect concealed objects on a person without physical contact, but they use different methods to achieve this. Knowing the distinction helps clarify the nature of the energy exposure.

• Millimeter Wave Scanners: These are the most common scanners seen in airports today. They use non-ionizing radiofrequency energy to create a 3D image of the body.
• Backscatter X-ray Scanners: While less common now, some airports may still use these. They employ very low-dose ionizing X-rays to create a 2D image.

Both technologies are regulated and continuously evaluated by federal agencies to ensure they meet safety standards for public exposure.

Millimeter Wave Scanners: Radiofrequency Energy

The majority of advanced imaging technology (AIT) units currently deployed in airports are millimeter wave scanners. These devices emit radiofrequency waves, similar to those used in cell phones, Wi-Fi routers, and even satellite television. The key distinction here is that millimeter waves use non-ionizing radiation.

Non-ionizing radiation refers to energy that is not strong enough to remove electrons from atoms or molecules, which is the process that can cause DNA damage. Instead, the millimeter waves penetrate clothing by a very small amount, reflect off the skin, and a computer then constructs an image based on these reflections. The energy levels are exceedingly low and are absorbed only at the very surface of the skin. The FDA, which oversees radiation-emitting electronic products, confirms that these systems operate well within accepted safety guidelines and present no known health risks.

Exposure from a single scan is comparable to the radiofrequency energy you might encounter during everyday activities, often significantly less than what you receive from holding a cell phone to your ear for several minutes.

Backscatter X-ray Scanners: Ionizing Radiation

Backscatter X-ray scanners, though less prevalent than millimeter wave systems, use a different type of energy: ionizing radiation. This is the same type of energy found in medical X-rays, but the dose delivered by airport scanners is significantly lower. Ionizing radiation, at high doses, can potentially damage cells and DNA.

However, the dose from an airport backscatter scan is extremely small. To put it into perspective, a single scan delivers about 0.00005 mSv (millisieverts) of radiation. For comparison:

• The average person receives about 3 mSv of natural background radiation annually from cosmic rays, soil, and building materials.
• A typical cross-country flight exposes a traveler to about 0.035 mSv of cosmic radiation due to higher altitude.
• A standard chest X-ray delivers approximately 0.1 mSv.

This means a single backscatter scan is equivalent to roughly 3-9 minutes of natural background radiation exposure or the cosmic radiation received during a few minutes on an airplane. Federal agencies like the FDA and the National Institute for Standards and Technology (NIST) have rigorously tested these systems and determined that the radiation exposure is well within safe limits for the general public, even for frequent travelers.

Addressing Specific Concerns: Pregnancy, Medical Devices, and Children

Travelers often have particular concerns regarding airport scanners, especially for vulnerable groups. It’s helpful to understand the guidelines and options available.

Pregnancy

For pregnant travelers, both millimeter wave and backscatter X-ray technologies are generally considered safe. Millimeter wave scanners use non-ionizing radiofrequency energy that does not penetrate beyond the skin’s surface and poses no known risk to a developing fetus. While backscatter X-ray scanners use ionizing radiation, the dose is so minuscule and localized to the skin surface that it is not considered a risk to the fetus. However, if a pregnant traveler prefers to avoid any radiation exposure, they always have the option to request a pat-down instead of going through the scanner.

Medical Devices

Individuals with implanted medical devices such as pacemakers, defibrillators, cochlear implants, or insulin pumps can safely pass through both types of advanced imaging technology scanners. These devices are designed to withstand common electromagnetic fields and low-dose radiation. The energy levels from airport scanners are not strong enough to interfere with or damage these devices. Travelers with concerns can always inform the security officer about their device and request a modified screening procedure, which might include a visual inspection or a pat-down.

Children

Children, including infants, are routinely screened using advanced imaging technology. The safety standards applied to these scanners account for all age groups. The minimal exposure from millimeter wave or backscatter X-ray scanners is not considered harmful to children. As with adults, parents can request a pat-down for their child if they prefer, though this is not medically necessary.

Table 1: Airport Scanner Types & Key Characteristics

Scanner Type	Technology	Energy Type
Millimeter Wave	Radiofrequency waves	Non-ionizing
Backscatter X-ray	Low-dose X-rays	Ionizing

The Pat-Down Alternative: Your Rights and Options

Travelers always have the option to decline advanced imaging technology screening and request a physical pat-down, a right affirmed by the TSA. This choice is available to anyone, regardless of their reason for opting out of the scanner. When you choose a pat-down, a security officer of the same gender will conduct a thorough physical search.

The pat-down procedure is designed to be respectful while ensuring security. It involves a methodical search of the body, including sensitive areas, through clothing. You can request a private screening area for the pat-down if you prefer. While it might take slightly longer than a scanner, it provides an alternative for those who wish to avoid any form of electronic screening or have specific medical concerns that make a pat-down a better option for them.

Table 2: Comparing Screening Options

Screening Method	Energy Exposure	Typical Experience
Millimeter Wave Scan	Extremely low non-ionizing RF	Quick, hands-free, automated
Backscatter X-ray Scan	Extremely low ionizing X-ray	Quick, hands-free, automated
Pat-Down	None	Physical touch, manual search

Scientific Consensus and Regulatory Oversight

The safety of airport scanners is a subject that has been extensively studied and reviewed by numerous scientific and health organizations globally. Agencies like the FDA, the Centers for Disease Control and Prevention (CDC), and the World Health Organization (WHO) have consistently concluded that the radiation and radiofrequency energy levels emitted by these scanners are well below harmful thresholds for human health. The consensus across these bodies is that the public health risk from airport security scanners is negligible.

Regulatory bodies continue to monitor and update standards for these devices. The purpose of these strict regulations is to ensure that while security is maintained, traveler health remains protected. This ongoing oversight provides a layer of assurance for travelers moving through security checkpoints.