Section 325.5407. Enclosures.

   (1) An enclosure shall be a permanent part   of   the   building   or equipment.

Portable shields shall not be used for permanent installations.

(2)     The degree of protection required for an enclosure shall be determined by  the workload, use and occupancy factors and the  kilovoltage, milliamperage, mechanical movement, and distance factor, and shall be subject to design approval by the department.

(3)   Radiographic-room wall and floor areas exposed to the useful beam plus an additional area extending at least 30 centimeters (1 foot) beyond shall be provided with a primary protective barrier where necessary as determined by workload, use, occupancy and distance factors. All vertical primary protective barriers specified in this rule shall extend continuously from the floor to a minimum height of 2.1 meters (7 feet).

(4)   Secondary protective barriers shall be provided in  the  radiographic room ceiling and in those walls not requiring primary barriers.

(5)     Control apparatus for the radiographic equipment shall be shielded by a primary protective barrier which cannot be removed from a protective position between the operator and the radiation source during machine operation.

(6)   Movable barriers with electrical interlocks shall not be approved in lieu of compliance with subrule (5).

(7)  The primary exposure switch location and control shield shall be oriented so that, at arm's length from the exposure switch, the operator shall not be exposed to the useful beam, leakage radiation or  any radiation which has been scattered only once.

(8)  The operator shall be able to see and communicate with personnel within the room from a shielded position at the control panel. When an observation window is provided, it shall have a lead equivalence at least equal to that required  of the control  barrier  and  shall  be installed so that the attenuation effectiveness of the barrier is not impaired.

(9)   At times it may be necessary for personnel to remain within operating room or special procedure installations during radiographic exposures. A primary protective barrier shall be provided for personnel protection under these circumstances unless necessary technique prevents use of  such protection.  This barrier may be  movable  if   necessary. Movable barriers shall not be permitted in lieu of the provisions of subrules (3) and (5).

History: 1979 AC.