The European Commission last week adopted new rules that prohibit the use of X-ray scanners for airport security screening.

The U.S. Transportation Security Administration uses both X-ray and millimeter wave technologies in its advanced imaging screening systems, but only the latter would be acceptable under European law. Despite concerns, TSA maintains that X-ray scanners, which emit a very low dose of radiation, are safe. EC, however, prohibited their use "in order not to risk jeopardizing citizens' health and safety." The EC directive, which replaces "a patchwork of different national operational procedures and standards," also set "minimum conditions" for using approved scanners, including a prohibition against retaining images and, as in the United States, a requirement that images be reviewed by personnel in a separate location. Passengers also can "opt out" of all scanning in favor of "an alternative method of screening," according to the EC directive.