NAC459.624. Other radiographic systems: Source to skin distance; exposure reproducibility; standby radiation.

     1. Except as otherwise provided in NAC 459.5595, all mobile or portable radiographic systems must be provided with a means to limit the source to skin distance to not less than 30 centimeters.

     2. The exposure produced must be reproducible to the following criteria: When all technique factors are held constant, the coefficient of variation must not exceed 0.10. This requirement is met if, when four exposures at identical technique factors are made, the value of the average exposure (E) is greater than or equal to five times the maximum exposure (E max) minus the minimum exposure (E min) in accordance with the formula: E 5 (E max-E min).

     3. Radiation emitted from the X-ray tube when the exposure switch or timer is not activated must not exceed a rate of 2 milliroentgens per hour at 5 centimeters from any accessible surface of the diagnostic source assembly, with the beam-limiting device fully open.

     [Bd. of Health, Radiation Control Reg. §§ 6.6.3-6.6.5, eff. 2-28-80]—(NAC A by R185-08, 5-7-2010)