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(f) The exposure switch must be of a dead-man type switch and must be arranged in a manner that the switch cannot be operated outside a shielded area, except that exposure switches for spot film devices used in conjunction with fluoroscopic tables and for mobile diagnostic radiographic equipment are exempt from this shielding requirement. (g) The exposure switch for mobile equipment must be arranged in a manner that the operator can stand at least six feet from the patient and well away from the useful beam. (h) The control panel must include

(1) a device that will give positive indication of the production of x-rays whenever the x-ray tube is energized; and

(2) appropriate devices that will give positive indication of the physical factors used for the exposure, such as kVp, mA, and exposure time. (i) All wall, floor, and ceiling areas that may intercept the useful beam must have primary barriers. (j) A primary barrier in a wall must extend to a height of at least 84 inches or 210 centimeters above the floor. (k) A secondary barrier must be provided in all wall, floor, and ceiling areas not having a primary barrier or where the primary barrier requirements are lower than the secondary barrier requirements. In a radiographic installation where the average radiographic workload is comparatively low, the conventional structural material in ordinary walls, floors, and ceilings may suffice as a primary barrier and secondary barrier without adding special shielding materials, particularly if the useful beam cannot be directed at occupied areas. (l) The operator’s station must be behind a protective barrier that will intercept the entire useful beam and any radiation that has been scattered only once. An operator must be unable to energize the tube while outside the protective barrier, except that spot film devices used in conjunction with fluoroscopic tables are exempted from this requirement. (m) A window of lead equivalent glass, equal to that required by the adjacent barrier, mirror system, or closed circuit television monitor, must be provided and it must be large enough and placed in a manner that the operator can see the patient during the exposure without having to leave the protective area. (n) If a patient must be held in position for radiography, a mechanical supporting, or restraining device must be used unless the device will interfere with the diagnosis. (o) If a patient must be held by an individual, that individual must be protected with appropriate shielding devices, such as protective gloves and apron, and that individual must be positioned in a manner that no part of that individual’s body will be struck by the useful beam. (p) An individual occupationally exposed to radiation may not hold a patient during an exposure, except during an emergency. An individual may not be regularly used for this service.