Section 2810. Design requirements

A. For all irradiators, licensees shall evaluate the location and sensitivity of the monitor to detect sources carried by the product conveyor system as required by 12VAC5-481-2760 A. Licensees shall verify that the product conveyor is designed to stop before a source on the product conveyor would cause a radiation overexposure to any person.

B. For panoramic irradiators:

1. Licensees shall design shielding walls to meet generally accepted building code requirements for reinforced concrete and design the walls, wall penetrations, and entrance ways to meet the radiation shielding requirements of 12VAC5-481-2740. If the irradiator will use more than 5 million curies (2 x 10¹⁷ Bq) of activity, licensees shall evaluate the effects of heating of the shielding walls by the irradiator sources.

2. Licensees shall design the foundation, with consideration given to soil characteristics, to ensure it is adequate to support the weight of the facility shield walls.

3. Licensees shall verify from the design and logic diagram that the access control system will meet the requirements of 12VAC5-481-2730.

4. Licensees shall verify that the number, locations, and spacing of the smoke and heat detectors are appropriate to detect fires and that the detectors are protected from mechanical and radiation damage. Licensees shall verify that the design of the fire extinguishing system provides the necessary discharge patterns, densities, and flow characteristics for complete coverage of the radiation room and that the system is protected from mechanical and radiation damage.

5. Licensees shall verify that the source rack will automatically return to the fully shielded position if offsite power is lost for more than 10 seconds.

6. Licensees shall verify that electrical wiring and electrical equipment in the radiation room are selected to minimize failures due to prolonged exposure to radiation.

7. Licensees shall determine that source rack drops due to loss of power will not damage the source rack and that source rack drops due to failure of cables (or alternate means of support) will not cause loss of integrity of sealed sources.

8. Licensees shall review the design of the mechanism that moves the sources to assure that the likelihood of a struck source is low and that, if the rack sticks, a means exists to free it with minimal risk to personnel.

9. For panoramic irradiators to be built in seismic areas, licensees shall design the reinforced concrete radiation shields to retain their integrity in the event of an earthquake by designing to the seismic requirements of an appropriate source or local building codes, if current.

D. For pool irradiators:

1. Licensees shall design the pool to assure that it is leak resistant, that it is strong enough to bear the weight of the pool water and shipping casks, that a dropped cask would not fall on sealed sources, that all outlets or pipes meet the requirements of 12VAC5-481-2780 C, and that metal components are metallurgically compatible with other components in the pool.

2. Licensees shall verify that the design of the water purification system is adequate to meet the requirements of 12VAC5-481-2780 E. The system shall be designed so that water leaking from the system does not drain to unrestricted areas without being monitored.

3. Licensees shall verify that there are no crevices on the source or between the source and the source holders that would promote corrosion on a critical area of the source.

4. If licensees use radiation monitors to detect contamination under 12VAC5-481-2870 B, they shall verify that the design of radiation monitoring systems to detect pool contamination includes sensitive detectors located close to where contamination is likely to concentrate.

Historical Notes

Derived from Volume 22, Issue 25, eff. September 20, 2006; amended, Virginia Register Volume 24, Issue 18, eff. June 12, 2008; Volume 32, Issue 24, eff. August 25, 2016.

Statutory Authority

§ 32.1-229 of the Code of Virginia.