The Transportation Security Administration maintains the machines are safe . But a new report from the Government Accountability Office found that TSA agents have been using them to search passengers without proper authorization. A critic complains the study was based on TSA data instead of independent testing .
The Transportation Security Administration maintains the machines are safe . The backscatter dose is `` comparable '' to one minute of exposure to cosmic radiation . A critic complains the study was based on TSA data instead of independent testing .