Code of Massachusetts Regulations › 105 CMR - DEPARTMENT OF PUBLIC HEALTH › Title 105 CMR 120.000 - The Control of Radiation › REPORTS › Section 120.659 - Design Requirements

Current through Register 1525, July 5, 2024
Irradiators whose construction began after July 1, 1993, must
				  meet the design requirements of 105 CMR 120.659.
(A)
Shielding
: For
				panoramic irradiators, the licensee shall design shielding walls to meet
				generally accepted building code requirements for reinforced concrete and
				design the walls, wall penetrations, and entranceways to meet the radiation
				shielding requirements of
				105 CMR 120.645. If the
				irradiator will use more than five million curies (2 x
				1017 becquerels) of activity, the licensee shall
				evaluate the effects of heating of the shielding walls by the irradiator
				sources.
(B)
Foundations
: For panoramic irradiators, the licensee
				shall design the foundation, with consideration given to soil characteristics,
				to ensure it is adequate to support the weight of the facility shield
				walls.
(C)
Pool
				Integrity
: For pool irradiators, the licensee 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
				105 CMR
				120.653(B), and that metal
				components are metallurgically compatible with other components in the
				pool.
(D)
Water
				Handling System
: For pool irradiators, the licensee shall verify
				that the design of the water purification system is adequate to meet the
				requirements of
				105 CMR
				120.653(E). The system must
				be designed so that water leaking from the system does not drain to
				unrestricted areas without being monitored.
(E)
Radiation
				Monitors
: For all irradiators, the licensee shall evaluate the
				location and sensitivity of the monitor to detect sources carried by the
				product conveyor system as required by
				105 CMR
				120.649(A). The licensee
				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. For
				pool irradiators, if the licensee uses radiation monitors to detect
				contamination under
				105 CMR
				120.679(B), the licensee
				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.
(F)
Source Rack
: For pool irradiators, the licensee shall
				verify that there are no crevices on the source or between the source and
				source holder that would promote corrosion on a critical area of the source.
				For panoramic irradiators, the licensee 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. For panoramic irradiators, the licensee shall
				review the design of the mechanism that moves the sources to assure that the
				likelihood of a stuck source is low and that, if the rack sticks, a means
				exists to free it with minimal risk to personnel.
(G)
Access Control
:
				For panoramic irradiators, the licensee shall verify from the design and logic
				diagram that the access control system will meet the requirements of
				105 CMR
				120.643.
(H)
Fire Protection
:
				For panoramic irradiators, the licensee 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. The licensee 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.
(I)
Source Return
:
				For panoramic irradiators, the licensee shall verify that the source rack will
				automatically return to the fully shielded position if offsite power is lost
				for more than ten seconds.
(J)
Seismic
: For panoramic irradiators to be built in
				seismic areas, the licensee 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 such as American Concrete
				Institute Standard ACI 318-89,
Building Code Requirements for
				Reinforced Concrete
, Chapter 21,
Special Provisions for
				Seismic Design
, or local building codes, if current.
(K)
Wiring
: For
				panoramic irradiators, the licensee shall verify that electrical wiring and
				electrical equipment in the radiation room are selected to minimize failures
				due to prolonged exposure to radiation.