PDFWAC 246-236-025

Shielding.

(1) The radiation dose rate in areas that are normally occupied during operation of a panoramic or beam-type irradiator may not exceed two-hundredths millisievert (two millirems) per hour at any location thirty centimeters or more from the wall of the room when the sources are exposed. The dose rate must be averaged over an area not to exceed one hundred square centimeters having no linear dimension greater than twenty centimeters. Areas where the radiation dose rate exceeds two-hundredths millisievert (two millirems) per hour must be locked, roped off, or posted.
(2) The radiation dose at thirty centimeters over the edge of the pool of a pool irradiator may not exceed two-hundredths millisievert (two millirems) per hour when the sources are in the fully shielded position.
(3) The radiation dose rate at one meter from the shield of a panoramic or beam-type dry-source-storage irradiator when the source is shielded may not exceed two-hundredths millisievert (two millirems) per hour and at five centimeters from the shield may not exceed two-tenths millisievert (twenty millirems) per hour.
[Statutory Authority: RCW 70.98.050, 70.98.110 and 58 F.R. 7728, 76 F.R. 56963, 77 F.R. 39906, 80 F.R. 54234. WSR 18-15-017, § 246-236-025, filed 7/9/18, effective 8/9/18.]