The Transportation Security Administration (TSA) is in compliance with standards set forth to verify the safe radiation dose emitted by whole body imagers based on X-ray technology, and furthermore these scanning systems emit minimal radiation on people that are being screened, the Department of Homeland Security’s Inspector General (IG) says in a new report (OIG-12-38).
The report’s conclusions didn’t mollify Sen. Susan Collins (R-Maine), who remains concerned that there hasn’t been an independent study conducted to confirm that the backscatter X-ray-based Advanced Imaging Technology (AIT) systems do not emit potentially harmful levels of radiation on people being screened.
“An independent study is needed is needed to protect the public and determine what technology is worth of taxpayer dollars,” Collins, who is the ranking member on the Senate Homeland Security and Governmental Affairs Committee, said in a statement yesterday following the report’s release. “Among other things, such a study should examine the risk of backscatter X-ray technology from a public health perspective in addition to the potential risk to individuals and TSA employees.”
Collins had already introduced legislation that would require an independent assessment of the health effects of the backscatter-based AIT systems on frequent fliers, pregnant women and TSA employees. The backscatter AIT systems are supplied by OSI Systems [OSIS] Rapiscan division. TSA also buys the whole body imagers from L-3 Communications [LLL], whose systems are based on millimeter wave technology and do not emit ionizing radiation.
The IG report essentially cites previous studies into the health effects of the backscatter AIT systems, all of which found that the radiation doses they emit are well below acceptable limits determined by the standards-setting body the American National Standards Institute (ANSI). Those studies include assessments by the Food and Drug Administration, a third party assessment sponsored by Rapiscan to assure ANSI compliance, another conducted by a branch of the Commerce Dept., the National Institute of Standards and Technology, and a final one done by the Johns Hopkins Univ. Applied Research Laboratory.
The IG also says that TSA has procedures in place to “ensure that radiation safety surveys are conducted ruing specific intervals and when circumstances dictate” as required by ANSI.
The report makes several recommendations, all of which TSA agrees with. These include the agency having a process to do radiation surveys on any backscatter units if they have been damaged, develop controls to ensure the system calibrations are done consistently and are properly documented, and that Transportation Security Officers meet requirements for radiation safety training and for operating the backscatter systems.