The Transportation Security Administration (TSA) has started
removing X-ray body scanners from major airports. The decision is said to have
been based purely on speeding up the check-in process and not because of safety
concerns.
X-ray scanners have been a concern for travelers for quite some time. The scanners emit a small dose of ionizing radiation, which at higher levels has been linked to cancer. Passengers have also known to be uncomfortable with the fact that the scanners produced blurred pictures of passengers’ naked bodies. Each picture must be reviewed by a TSA officer, which slows down security lines.
The alternative to the X-ray scanner is the millimeter-wave
scanner. These machines rely on low-energy radio waves. Instead of creating a
picture, a computer algorithm looks for anomalies and depicts them as a yellow
box on a cartoon figure. The millimeter-wave scanner is also highly effective
at finding explosives.
One drawback to the millimeter-wave scanner is the high
false-alarm rate. Studies in Europe and Australia have found the false-alarm
rate to range between 23% and 54%, compared to the reported 5% false-alarm rate
for the X-ray scanner. At any rate, the millimeter-wave scanners appear to be
very effective and are more time efficient than the X-ray scanner. There are
also no known DNA damaging or cancer causing mechanisms in these types of
waves.
Although TSA has begun moving the X-ray scanners from major
airports to smaller, less crowded airports, that does not mean they are being
phased out completely. The X-ray scanners are still in place at a few major US
airports. Furthermore, TSA has recently awarded three companies potential
contracts for the next generation of body scanners. Of those three companies,
one uses the X-ray technology in their scanner. Have we seen the beginning of
the end of the dreaded X-ray scanners? Only time will tell.
