To improve airport security in the light of terrorist threats new full-body scanners have been developed to complement existing metal detectors and hand searches. Scanner types that do not use X-rays – “millimeter wave scanners” – are already allowed in the EU and deployed in some airports. Other types of scanners already used in the USA expose passengers to low levels of X-rays. They are not yet authorised in the EU because of concern about potential health risks. How safe are such X-ray security scanners for passengers, in particular for frequent flyers?

1. X-Ray Full-Body
Scanners for
Airport Security
To improve airport security in the 1 OW MUCH RADIATION ARE
H the tolerable limit. In practice, most
light of terrorist threats new full-body PEOPLE EXPOSED TO IN X-RAY passengers would not be exposed so
scanners have been developed to SCANNERS? frequently to these scanners. This may
complement existing metal detectors however be a concern for airline crew
and hand searches. When exposed to X-rays our body or people who fly very frequently.
absorbs energy, the amount of energy
Scanner types that do not use X-rays effectively absorbed over time is 1 OES EXPOSURE TO X-RAYS FROM
D
– “millimeter wave scanners” – expressed in “sievert” (Sv). Over the SCANNERS PRESENT HEALTH RISKS?
are already allowed in the EU and course of one year, a person should not
deployed in some airports. Other be exposed to more than a total of 1 Exposure to high levels of X-rays
types of scanners already used in the millisievert from man-made sources can increase the risk of cancer and
USA expose passengers to low levels such as medical diagnostic devices or cardiovascular diseases, lead to
of X-rays. They are not yet authorised security scanners. This is the maximum cloudiness of the lens of the eye and
in the EU because of concern about acceptable limit set for the general hereditary effects.
potential health risks. How safe public and is roughly equivalent to the However, there is no evidence that the
are such X-ray security scanners for amount of natural radiation we are low radiation doses received from full-
passengers, in particular for frequent also exposed to. body scanners would induce any health
flyers?
Transmission scanners that see into the problems. Nonetheless, each exposure
1 OW DO THOSE FULL-BODY
H body use higher energy X-rays than adds to the overall radiation dose we
SCANNERS WORK? Backscatter scanner that only view the receive in the course of our life and in
surface and as a result the dose absorbed the long term, the risk of developing
Whole body scanners provide a picture is 10 times greater. A single scan is cancer increases with radiation dose.
of the person’s body through the roughly the equivalent of one hour of While no dose can be considered
clothes to reveal hidden objects. Four background radiation at ground level, completely safe, it is likely that the
technologies are currently on the or 10 minutes at cruising altitude in an increased cancer risk from exposure to
market: airplane. In the worst case scenario, of a radiation from security scanners is so
Millimeter-wave scanners, that don’t person being scanned three times a day low that it cannot be distinguished from
use X-rays: every working day throughout the year, the effects of natural radiation or the
1. assive scanners detect the very low
P a backscatter scanner would contribute background risk due to other factors.
levels of natural radiation emanating 0,3 millisievert to their annual dose. A Direct evidence of an increased cancer
from the body surface. transmission scanner, however, would risk has only been found for cumulative
2. ctive scanners emit radio waves
A contribute 3 millisievert and exceed doses higher than 100 millisievert.
that are reflected back by the body
surface.
X-ray scanners: 1 S THE USE OF FULL-BODY X-RAY SCANNERS JUSTIFIED ?
I
3. ackscatter scanners emit low energy
B
X-rays that are reflected back by the To decide whether or not the use health risks. So, whether or not X-ray
body surface. of X-ray scanners is acceptable, it is scanners are acceptable for passenger
4.
Transmission scanners send higher necessary to weigh the benefits and screening is ultimately not a scientific,
energy X-rays through the body in risks but this is not straightforward. The but a political decision that needs to
the same way as a traditional medical main benefit is improved flight safety take into account various factors.
X-ray machine and can reveal objects but there are economic costs and low
inside the body.
This fact sheet is based on the scientific opinion “Health effects of security The detailed and nuanced view of the European Scientific Committee
scanners for passenger screening (based on X-ray technology)” adopted on Consumer Safety on this issue is available at:
on 26 April 2012 by the independent European Scientific Committee on
Emerging and Newly Identified Health Risk. http://ec.europa.eu/health/scientific_committees/
emerging/docs/scenihr_o_036.pdf
SCIENTIFIC COMMITTEES