Are Airport Full Body Scanners Safe? | Your Guide

Airport full body scanners use extremely low-level radiation or millimeter wave technology, generally considered safe for most travelers.

Stepping through airport security is a routine part of travel, and those full body scanners have become a familiar sight. Many of us wonder about the technology behind them and if they pose any risks to our health. Let’s break down what these scanners do and what the science says.

The Technology Behind Airport Scanners

Airport security checkpoints primarily use two types of advanced imaging technology (AIT) scanners. The most common type in use today relies on millimeter wave technology, while an older, less common type used backscatter X-ray technology.

Millimeter Wave Scanners: How They Work

Millimeter wave scanners use non-ionizing electromagnetic waves, similar to radio waves, to create an image. These waves reflect off the skin and any objects concealed under clothing. The system then generates a generic, privacy-protective outline of a person, highlighting any anomalies for security officers to review.

The energy emitted by millimeter wave scanners is very low power. It does not penetrate the body or alter human cells. This technology is distinct from ionizing radiation used in medical X-rays.

The Phasing Out of Backscatter X-ray Scanners

Backscatter X-ray scanners, which used a very low dose of ionizing radiation, were once deployed in some airports. These devices generated a detailed anatomical image, though privacy software obscured specific body parts.

Due to public concerns and the availability of millimeter wave technology, backscatter X-ray scanners have been largely phased out of service in US airports. The vast majority of AIT machines encountered today are millimeter wave systems.

Understanding Radiation Exposure

The primary concern for many travelers revolves around radiation exposure. It’s important to differentiate between the types of radiation and their effects.

Millimeter wave scanners use non-ionizing radiation, which means it does not have enough energy to remove electrons from atoms or molecules. This type of radiation is found in everyday items like cell phones and Wi-Fi signals. Ionizing radiation, found in medical X-rays and backscatter scanners, carries enough energy to potentially cause cellular damage, though the doses from airport scanners were always very small.

Comparing Scanner Radiation to Everyday Life

The radiation dose from a single scan by a millimeter wave machine is negligible. To put it into perspective, the exposure is significantly less than the natural background radiation everyone receives daily from cosmic rays, the earth, and even certain foods.

A single airport scan delivers a radiation dose equivalent to just a few minutes of flying at cruising altitude. For context, a cross-country flight exposes passengers to more cosmic radiation than a full body scanner.

Official Health & Safety Assessments

Multiple independent and government scientific bodies have evaluated the safety of airport body scanners. Their findings consistently indicate that the radiation exposure from these devices is minimal and falls within safe limits.

The FDA, responsible for regulating radiation-emitting electronic products, has consistently affirmed the safety of these scanners, stating that the radiation dose is extremely small. Other organizations, including the National Institute of Standards and Technology (NIST) and the Health Physics Society, support these conclusions.

These assessments consider the cumulative effect of multiple scans over time for frequent travelers. Even for individuals who fly often, the total exposure remains well below established safety thresholds.

Comparison of Advanced Imaging Scanner Types

Feature	Millimeter Wave Scanner	Backscatter X-ray Scanner
Technology	Non-ionizing radio waves	Ionizing X-rays
Radiation Type	Electromagnetic (radio)	Ionizing
Current Use (US Airports)	Widespread	Mostly phased out
Image Output	Generic avatar	Anatomical image (obscured)

Special Considerations for Travelers

While general consensus points to the safety of these scanners, some travelers have specific health considerations or preferences.

Pregnancy and Children

For pregnant individuals, the consensus among health experts is that millimeter wave scanners pose no known risk. The non-ionizing radiation does not penetrate the body. For children, the exposure is also considered safe and negligible.

Despite the scientific consensus, some pregnant travelers prefer to opt for a pat-down for personal comfort or a heightened sense of caution. This is always an available option.

Medical Implants and Devices

Travelers with medical implants like pacemakers, defibrillators, or artificial joints can safely pass through millimeter wave scanners. The technology does not interfere with or damage these devices. Metal implants will typically trigger an alert on the scanner, leading to a targeted pat-down of that specific area.

It’s always a good practice to inform the security officer about any medical devices or implants before screening begins. This helps streamline the process.

Your Options at the Checkpoint

Travelers always have a choice regarding how they are screened at the airport checkpoint.

The TSA states that all passengers have the option to decline advanced imaging technology screening and request a pat-down instead. This is a traveler’s right and should be respected by security personnel.

Requesting a Pat-Down

If you choose to opt out of the scanner, simply inform the security officer before you enter the machine. You will then be directed to a secondary screening area for a pat-down. This is a physical search conducted by a same-gender officer.

A pat-down can take slightly longer than a scanner screening. It involves a thorough physical check of your person and clothing. You can request that the pat-down be conducted in a private screening area, away from public view.

Quick Guide: Opting for a Pat-Down

Scenario	Action	What to Expect
General Traveler	Inform the officer before scanning	Private screening available, same-gender officer
Medical Device	Inform officer, provide documentation if available	May still require pat-down or specific check
Pregnancy	Inform officer	Pat-down often recommended or preferred by traveler

Addressing Common Traveler Concerns

Beyond radiation, travelers often have questions about privacy and the effectiveness of these scanners.

Privacy and Image Retention

Millimeter wave scanners generate a generic, stick-figure-like outline of a person, not a photographic image. This outline is reviewed by a security officer in a separate location, ensuring the officer at the checkpoint does not see the image. The image is immediately deleted once the passenger is cleared.

No personal identifying information is associated with the image, and the systems are designed not to store or transmit any images. This design addresses privacy concerns by ensuring anonymity and immediate deletion.

Effectiveness in Security

Advanced imaging technology scanners are highly effective at detecting metallic and non-metallic objects hidden under clothing. They are designed to identify a wide range of threats, including weapons, explosives, and other prohibited items that might not be visible to the naked eye or detectable by traditional metal detectors.

The implementation of these scanners has significantly enhanced aviation security by providing a more comprehensive screening method for passengers.

Making Your Security Choice

Understanding the technology and the official assessments can help travelers feel more confident about airport security procedures. The scientific community widely agrees that millimeter wave scanners pose no significant health risk due to their non-ionizing, low-power emissions.

For those who prefer not to use the scanner for any reason, the option of a pat-down is always available. This choice allows individuals to align their personal comfort with security requirements.