(Center for Devices and Radiological Health) A branch of the U.S. Food and Drug Administration that governs medical devices as well as non-medical devices that emit radiation, such as cellphones. Classes 3, 2 and 1 Class 3 devices are the most critical and must go through rigorous testing before approval, similar to pharmaceutical drugs. Class 2 devices are considered low risk, and manufacturers go through a less rigorous "510k" approval process for new models that are similar to existing products. However, a report released in 2011 by the National Research Center for Women and Families and the Cleveland Clinic showed that several 510k-approved devices in the previous five years had caused serious health problems when they failed to operate properly. Class 1 devices are harmless to users if they fail to operate. See healthcare IT.