R 333.5012 Definitions; T to V.

Rule 12. (1) “Traceable to a national standard” means an instrument is calibrated at either the national institute of standards and technology (NIST) or at a calibration laboratory that participates in a proficiency program with the NIST at least once every 2 years and the results of the proficiency test conducted within 24 months of calibration show agreement within 3% of the national standard in the appropriate energy range. (2) "Unrestricted area" or “uncontrolled area” means an area, access to which is neither limited nor controlled by the registrant for purposes of protection of individuals from exposure to radiation, or an area used for residential quarters. (3) "Very high radiation area" means an area, accessible to individuals, in which radiation levels from a radiation machine could result in an individual receiving an absorbed dose in excess of 5 Gy (500 rads) in 1 hour at 1 meter from a radiation machine or 1 meter from any surface that the radiation penetrates.