The use of ultraviolet germicidal irradiation (UVGI) devices for killing/inactivating microorganisms on surfaces is becoming increasingly common. UVGI devices, ranging from whole-room disinfectors to small appliance-type units, are used to kill/inactivate microorganisms on surfaces. Many of these devices are used in health care settings, but currently there is no oversight by U.S. regulators. This is partly due to a lack of standard methods to validate claims. ARA helped fill this gap by developing the first ever consensus standard for evaluation of UVGI surface decontamination.