This specification covers infrared thermometers, which are electronic instruments intended for the intermittent measurement and monitoring of patient temperatures by means of detecting the intensity of thermal radiation between the subject of measurement and the sensor. The specification addresses the assessment of the subject's internal body temperature through measurement of thermal emission from the ear canal. Though, performance requirements for noncontact temperature measurement of skin are also provided. Limits are set for laboratory accuracy, and determination and disclosure of clinical accuracy of the covered instruments are required. Performance and storage limits under various environmental conditions, requirements for labeling, and test procedures are all established herein.