1. (1) The protective tube housing shall be of diagnostic type.
2. (2) Collimating devices capable of restricting the useful beam to the area of clinical interest shall be used and shall provide the same degree of protection as is required of the tube housing.
3. (3) The X-ray films used as the recording medium during the X-ray examination shall show substantial evidence of cut-off (beam delineation).

4. (4) The aluminum equivalent of the total filtration in the useful beam shall not be less than that shown below:

   Operating kVp	Minimum total filtration (Inherent plus added)
   Below 50 kVp	0.5 mm aluminum
   50-70 kVp	1.5 mm aluminum
   Above 70 kVp	2.5 mm aluminum

5. (5) A device shall be provided which terminates the exposure after a preset time interval or exposure.
6. (6) All mobile, portable or beside equipment shall be provided with cones or metal frames so that the minimum source to skin distance is at least 12 inches.

7. (7) The exposure switch shall be of the dead-man type and shall be provided with a cord sufficiently long that the operator can stand at least six feet from the patient, the X-ray tube and the useful beam.

   (b) Use.

   If a mobile unit is used routinely in one location it shall be considered a fixed installation, and shall meet the requirements of section 16.56 of this Part.

   (c) Conditions for operation of equipment.

8. (1) No person shall be regularly employed to hold patients or films during exposures nor shall such duty be performed by any individual occupationally exposed to radiation during the course of his/her other duties. When it is necessary to restrain the patient, mechanical supporting or restraining devices shall be used. If patient or films must be held by an individual, that individual shall be protected with appropriate shielding devices such as protective gloves and a protective apron of at least 0.25 mm lead equivalent. No part of the attendant's body shall be in the useful beam. The exposure of any individual used for holding patients shall be monitored. Pregnant women and persons under 18 years of age shall not hold patients under any conditions.
9. (2) Gonadal shielding of not less than 0.5 mm lead equivalent shall be used for patients who have not passed the reproductive age during radiographic procedures in which the gonads are in the useful beam, except for cases in which this would interfere with the diagnostic procedure.

(a) Equipment.