Millions of fliers pass through them, but scientific experts are still at odds about the safety of full-body airport scanners that use an X-ray technology called backscatter. The machines use low-level beams to create an image of the body, revealing weapons or other concealed items beneath a passenger’s clothing.
The scanners emit very small doses of ionizing radiation, which is known to cause cellular changes in larger doses. Rapiscan, the company that manufactures the backscatter machines used in airports, says that the radiation dose of one scan is equivalent to two minutes of air travel at 30,000 feet.
