The NIST-traceable Radiometer is used to calibrate the proper level of UVC energy when fixtures are in use during a procedure; and to ensure overall proper system operation. The user simply positions the radiometer on the table, pushes a button on the controller - the system takes over and runs a full calibration cycle entirely by itself. All performance data, and energy levels, are recorded and stored on the hard drive inside the controller. When the procedure mode is selected the surface mount, or direct mount units will automatically emit the proper reduced level of energy; when the disinfection mode is selected all fixtures, including the direct units, ramp up to 100% of power in order to provide the highest intensity for the shortest cycle times. American Ultraviolet currently recommends to periodically perform a calibration cycle, which typically takes 10-15 minutes (no staff is required to be present during this time).