Minnesota Administrative Rules

4731.6070 SHIELDING.

Subpart 1.

Panoramic irradiators.

For panoramic irradiators, the radiation dose rate in areas that are normally occupied during operation may not exceed two millirems (0.02 mSv) per hour at any location 30 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 100 square centimeters having no linear dimension greater than 20 centimeters. Areas where the radiation dose rate exceeds two millirems (0.02 mSv) per hour must be locked, roped off, or posted.

Subp. 2.

Dry-source-storage panoramic irradiators.

For dry-source-storage panoramic irradiators, the radiation dose rate at one meter from the shield when the source is shielded may not exceed two millirems (0.02 mSv) per hour and at five centimeters from the shield may not exceed 20 millirems (0.2 mSv) per hour.

Subp. 3.

Pool irradiators.

For pool irradiators, the radiation dose at 30 centimeters over the edge of the pool may not exceed two millirems (0.02 mSv) per hour when the sources are in the fully shielded position.

Statutory Authority:

MS s 144.1202; 144.1203

History:

29 SR 755

Published Electronically:

March 12, 2009