Equipment Requirements

(A) Safety Device. A device which prevents the entry of any portion of an individual's body into the primary x-ray beam path or which causes the beam to be shut off upon entry into its path shall be provided on all open-beam configurations. A registrant [or licensee] may apply to the Agency for an exemption from the requirement of a safety device. Such application shall include: (1) A description of the various safety devices that have been evaluated; (2) The reason each of these devices cannot be used; and, (3) A description of the alternative methods that will be employed to minimize the possibility of an accidental exposure, including procedures to assure that operators and others in the area will be informed of the absence of safety devices. (B) Warning Devices. (1) Open-beam configurations shall be provided with a readily discernible indication of: (a) X-ray tube "on-off" status located near the radiation source housing, if the primary beam is controlled in this manner; and/or, (b) Shutter "open-closed" status located near each port on the radiation source housing, if the primary beam is controlled in this manner. (2) Warning devices shall be labeled so that their purpose is easily identified. On equipment installed after the effective date of 105 CMR 120.600, warning devices shall have fail-safe characteristics. (C) Ports. Unused ports on radiation source housings shall be secured in the closed position in a manner which will prevent casual opening. (D) Labeling. All analytical x-ray equipment shall be labeled with a readily discernible sign or signs bearing the radiation symbol and the words: (1) "CAUTION - HIGH INTENSITY X-RAY BEAM", or words having a similar intent, on the x-ray source housing; and, (2) "CAUTION RADIATION - THIS EQUIPMENT PRODUCES RADIATION WHEN ENERGIZED", or words having a similar intent, near any switch that energizes an x-ray tube if the radiation source is an x-ray tube; or, (3) "CAUTION - RADIOACTIVE MATERIAL", or words having a similar intent, on the source housing in accordance with 105 CMR 120.237 and 120.238 if the radiation source is a radionuclide. (E) Shutters. On open-beam configurations installed after the effective date of 105 CMR 120.600, each port on the radiation source housing shall be equipped with a shutter that cannot be opened unless a collimator or a coupling has been connected to the port. (F) Warning Lights. (1) An easily visible warning light labeled with the words "X-RAY ON", or words having a similar intent, shall be located: (a) Near any switch that energizes an x-ray tube and shall be illuminated only when the tube is energized; or, (b) In the case of a radioactive source, near any switch that opens a housing shutter and shall be illuminated only when the shutter is open. (2) On equipment installed after the effective date of 105 CMR 120.600, warning lights shall have fail-safe characteristics. (G) Radiation Source Housing. Each radiation source housing shall be subject to the following requirements: (1) Each x-ray tube housing shall be equipped with an interlock that shuts off the tube if it is removed from the radiation source housing or if the housing is disassembled. (2) Each radioactive source housing or port cover or each x-ray tube housing shall be so constructed that, with all shutters closed, the radiation measured at a distance of five centimeters from its surface is not capable of producing a dose in excess of 2.5 millirems (0.025 mSv) in one hour. For systems utilizing x-ray tubes, this limit shall be met at any specified tube rating. (H) Generator Cabinet. Each x-ray generator shall be supplied with a protective cabinet which limits leakage radiation measured at a distance of five centimeters from its surface such that it is not capable of producing a dose in excess of 0.25 millirem (2.5 µSv) in one hour.