TSA challenges report it is bowing to criticism by testing workers for radiation

"TSA made a commitment to post new reports as they're completed to our website so passengers can see for themselves that the machines are meeting safety standards," the agency continued.

The LA Times reported that "[n]ews of the test leaked out after the TSA issued a request last month to government vendors to provide wearable, personal dosimeters, devices that measure exposure to radiation," but the agency said that too was normal.

"TSA routinely puts out Requests for Information (RFI) that are basically market research, asking industry to tell us what else is out there," the agency wrote. "In this case, TSA put out an RFI to gather information on available tools to continue to monitor our technologies. This is simply designed to ask industry what new technology might be available."

In addition to complaining that TSA's scanners expose travelers to radiation, critics have contended the X-ray machines also invade passenger's privacy.

TSA Administrator John Pistole has defended the machines, saying in a speech last spring that they were "the best possibility we have right now of detecting Christmas Day … type explosives," a reference to a thwarted 2009 bombing attempt on a Northwest Airlines flight bound for Detroit.

TSA has been also criticized for its procedure when passengers decline to go through X-ray scanners — pat downs. The agency has drawn fire for reportedly patting down an 8-month-old baby and allegedly strip-searching elderly passengers, which the agency has denied.

The agency has countered the criticism by releasing a series of reports of weapons it discovered that were concealed as such common items, such as a credit card, a belt buckle and a cell phone.