NAC459.658. Equipment requirements.

     1. A safety device which prevents the entry of any portion of a person’s body into the primary X-ray beam path or which causes the beam to be shut off upon entry into its path must be provided on all open-beam configurations. A registrant or licensee may apply to the Division for an exemption from the requirements of a safety device. Such an application must include:

     (a) A description of the various safety devices that have been evaluated;

     (b) The reason each of these devices cannot be used; and

     (c) A description of the alternative methods that will be employed to minimize the possibility of an accidental exposure, including procedures to ensure that operators and others in the area will be informed of the absence of safety devices.

     2. Open-beam configuration must be provided with a readily discernible indication of:

     (a) X-ray tube status whether on or off, located near the radiation source housing if the primary beam is controlled in this matter; or

     (b) Shutter status whether open or closed, located near each port on the radiation source housing if the primary beam is controlled in this manner.

     3. Warning devices must be so labeled that their purpose is easily identified. On equipment installed after February 28, 1980, warning devices must have fail-safe characteristics.

     4. Unused ports on radiation source housings must be secured in the closed position in a manner which will prevent casual openings.

     5. All analytical X-ray equipment must be labeled with a readily discernible sign bearing the radiation caution symbol and the words:

     (a) “CAUTION - HIGH INTENSITY X-RAY BEAM,” or words having a similar intent, on the X-ray source housing; and

     (b) “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

     (c) “CAUTION - RADIOACTIVE MATERIAL,” or words having a similar intent, on the source housing if the radiation source is a radionuclide.

     6. On open-beam configurations installed after February 28, 1980, each port on the radiation source housing must be equipped with a shutter that cannot be opened unless a collimator or a coupling has been connected to the port.

     7. An easily visible warning light labeled with the words “X RAY ON,” or words having a similar intent, must be located:

     (a) Near any switch that energizes an X-ray tube and 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 be illuminated only when the shutter is open.

     8. On equipment installed after February 28, 1980, warning lights must have fail-safe characteristics.

     9. Each X-ray tube housing must be constructed so that with all shutters closed the leakage radiation measured at a distance of 5 cm from its surface is not capable of producing a dose in excess of 2.5 mrem in 1 hour at any specified tube rating. If radioactive sources are used, corresponding dose limits must not exceed 2 mrem per hour.

     10. Each X-ray generator must be supplied with a protective cabinet which limits leakage radiation measured at a distance of 5 cm from its surface so that it is not capable of producing a dose in excess of 0.25 mrem in 1 hour.

     [Bd. of Health, Radiation Control Reg. §§ 8.3-8.3.8, eff. 2-28-80]