A group of five Republican and Democratic senators on the homeland security committee introduced a bill today that would require an independent health study of the X-ray body scanners used in airports nationwide.

We have been reporting on the cancer risk associated with the Transportation Security Administration’s scanners and on the expansion of X-ray equipment at the border, in prisons and on U.S. roads.

In addition to mandating a health study, the bill would also require the TSA to place larger signs in front of security lines advising airline passengers about the radiation and the option to have a physical pat-down instead.

“An independent study is needed to protect the public and to determine which technology is worthy of taxpayer dollars,” said Sen. Susan Collins, the top Republican on the homeland security committee. “Surely passengers should be well informed of their screening options.”