R 333.5505 Equipment.

Rule 505. (1) During all phases of operation of an electron microscope at the maximum rated continuous tube current for the maximum rated peak tube potential the radiation exposure rate as measured in air at a distance of 5 centimeters from an accessible point on the external surface of the microscope shall not exceed 0.5 milliroentgen per hour. (2) Interlocks shall be provided on all potential radiation hazard access panels which terminate exposure and prevent operation while the panel is removed. (3) The instrument shall display a conspicuous warning label such as “CAUTION RADIATION - THIS EQUIPMENT PRODUCES X-RADIATION WHEN ENERGIZED.” (4) Electron microscopes that are not capable of exceeding an operating potential of 50 kilovolts are exempt from the requirements of R 333.5505 to R 333.5508.