Washington Administrative Code › Title 246 - Health, Department of › RADIATION › Chapter 246-236 - Licenses and radiation safety requirements for irradiators › DESIGN AND PERFORMANCE REQUIREMENTS FOR IRRADIATORS › Section 246-236-039 - Design requirements

Current through Register Vol. 24-14, July 15, 2024
Irradiators whose construction begins after July 1, 1993,
					 must meet the design requirements of this section.
(1) Shielding. For panoramic or beam-type
				  irradiators, the licensee 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 WAC 246-236-025. If the irradiator will use more than two
				  hundred petabecquerels (five million curies) of activity, the licensee shall
				  evaluate the effects of heating of the shielding walls by the irradiator
				  sources.
(2) Foundations. For
				  panoramic or beam-type 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.
(3) 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 WAC 246-236-033(2), and that metal components are
				  metallurgically compatible with other components in the pool.
(4) 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 WAC 246-236-033(5).
				  The system must be designed so that water leaking from the system does not
				  drain to unrestricted areas without being monitored.
(5) 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 under WAC
				  246-236-029(1). The licensee shall verify that the product conveyor is designed
				  to stop before a source on the product conveyor would cause a radiation
				  over-exposure to any person. For pool irradiators, if the licensee uses
				  radiation monitors to detect contamination under WAC 246-236-059(2), 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.
(6) 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 or beam-type 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 or
				  beam-type 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.
(7) Access control. For
				  panoramic or beam-type irradiators, the licensee shall verify from the design
				  and logic diagram that the access control system will meet the requirements of
				  WAC 246-236-023.
(8) Fire
				  protection. For panoramic or beam-type irradiators, the licensee shall verify
				  that the number, location, 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.
(9) Source return. For
				  panoramic or beam-type irradiators, the licensee shall verify that the source
				  rack will automatically return to the fully shielded position if off-site power
				  is lost for more than ten seconds.
(10) Seismic. For panoramic or beam-type
				  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.
(11) Wiring. For panoramic or
				  beam-type 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.