The TSA has said it was privacy concerns — not radiation — that resulted in the agency canceling its contract with Rapiscan in January. Rapiscan, unlike the maker of the millimeter-wave machines, was unable to meet TSA's deadline to develop software to convert the nude-like images produced by their machines into stick-like figures, USA Today said.

The reports involve about 715 inspections and generally covered radiation tests from December 2011 through December 2012. USA TODAY's review found:

• While all reports showed radiation measurements below Rapiscan's standard of 5 microrem, the amount of radiation measured varies by machine. Eleven inspections showed radiation exposures of 1.3 microrem or less; 47 inspections showed radiation exposures at or above 2.6 microrem.

• Three body scanners had radiation readings of 3 microrem or higher. At Pittsburgh's airport a December 2011 inspection of one machine showed 3.9 microrem. In San Antonio, a scanner had radiation readings in February 2012 of 3 and 3.1 microrem. In Columbus, Ohio, tests showed a scanner delivering 3.3 and 3.4 microrem in December 2011.

• Measurements of radiation leakage outside the scanners rarely detected anything during a 10-scan test. In a few cases, tests detected 1 microrem of radiation leakage, below Rapiscan's standard of 2 microrem.

There is a 25 microrem per screening dose limit for such devices set by the American National Standards Institute.