North Dakota Administrative Code › Title 33.1 - Department of Environmental Quality › Article 33.1-10 - Radiological Health Rules › Chapter 33.1-10-15 - Therapeutic Radiation Machines › Appendix A - INFORMATION ON RADIATION SHIELDING REQUIRED FOR PLAN REVIEWS

Current through Supplement No. 393, July, 2024
1. All therapeutic radiation machines.
a. Basic facility information, including name, telephone
				  number, and department registration number of the individual responsible for
				  preparation of the shielding plan; name and telephone number of the facility
				  supervisor; and the street address (including room number) of the therapeutic
				  radiation machine facility. The plan should also indicate whether this is a new
				  structure or a modification to existing structures.
b. All wall, floor, and ceiling areas struck by the useful
				  beam shall have primary barriers.
c. Secondary barriers shall be provided in all wall, floor,
				  and ceiling areas not having primary barriers.
2. Therapeutic radiation machines up to 150 Kv (photons
				  only). In addition to the requirements listed in subsection 1, therapeutic
				  radiation machine facilities which produce only photons with a maximum energy
				  less than or equal to 150 kilovolts shall submit shielding plans which contain,
				  as a minimum, the following additional information:
a. Equipment specifications, including the manufacturer and
				  model number of the therapeutic radiation machine, as well as the maximum
				  technique factors;
b. Maximum design workload for the facility, including total
				  weekly radiation output, (expressed in gray (rad) or air kerma at 1 meter),
				  total beam-on time per day or week, the average treatment time per patient,
				  along with the anticipated number of patients to be treated per day or week;
c. A facility blueprint or drawing indicating: scale (0.25
				  inch = 1 foot is typical); direction of north, normal location of the
				  therapeutic radiation machine's radiation ports, the port's travel and traverse
				  limits, general directions of the useful beam, locations of any windows and
				  doors, and the location of the therapeutic radiation machine control panel. If
				  the control panel is located inside the therapeutic radiation machine treatment
				  room, the location of the operator's booth shall be noted on the plan and the
				  operator's station at the control panel shall be behind a protective barrier
				  sufficient to ensure compliance with subsection 1 of section
				  33.1-10-04.2-06 [
				  10 CFR
				  20.1201 ] of these regulations;
d. The structural composition and thickness or lead or
				  concrete equivalent of all walls, doors, partitions, floor, and ceiling of the
				  rooms concerned;
e. The type of occupancy of all adjacent areas inclusive of
				  space above and below the rooms concerned. If there is an exterior wall,
				  showing distance to the closest areas where it is likely that individuals may
				  be present; and
f. At least one example calculation which shows the
				  methodology used to determine the amount of shielding required for each
				  physical condition (i.e., primary and secondary leakage barriers, restricted
				  and unrestricted areas, entry doors) and shielding material in the facility:
(1) If commercial software is used to generate shielding
				  requirements, please also identify the software used and the version or
				  revision date.
(2) If the software used to generate shielding requirements
				  is not in the open literature, please also submit quality control sample
				  calculations to verify the result obtained with the software.
3. Therapeutic radiation machines over 150 kilovolts. In
				  addition to the requirements listed in subsection 1, therapeutic radiation
				  machine facilities that produce photons with a maximum energy in excess of 150
				  kilovolts or electrons shall submit shielding plans which contain, as a
				  minimum, the following additional information:
a. Equipment specifications, including the manufacturer and
				  model number of the therapeutic radiation machine, and gray (rad) at the
				  isocenter and the energies and types of radiation produced (i.e., photon,
				  electron). The target to isocenter distance shall be specified; b. Maximum
				  design workload for the facility, including total weekly radiation output
				  (expressed in gray (rad) at 1 meter), total beam-on time per day or week, the
				  average treatment time per patient, along with the anticipated number of
				  patients to be treated per day or week;
c. Facility blueprint or drawing (including both floor plan
				  and elevation view) indicating relative orientation of the therapeutic
				  radiation machine, scale (0.25 inch = 1 foot is typical), types, thickness, and
				  minimum density of shielding materials, direction of north, the locations and
				  size of all penetrations through each shielding barrier (ceiling, walls, and
				  floor), as well as details of the doors and maze;
d. The structural composition and thickness or concrete
				  equivalent of all walls, doors, partitions, floor, and ceiling of the rooms
				  concerned;
e. The type of occupancy of all adjacent areas inclusive of
				  space above and below the rooms concerned. If there is an exterior wall,
				  showing distance to the closest areas where it is likely that individuals may
				  be present;
f. Description of all assumptions that were in shielding
				  calculations, including design energy (i.e., room may be designed for 6 MV unit
				  although only a 4 MV unit is currently proposed), workload, presence of
				  integral beam-stop in unit, occupancy and uses of adjacent areas, fraction of
				  time that useful beam will intercept each permanent barrier (walls, floor, and
				  ceiling), and "allowed" radiation exposure in both restricted and unrestricted
				  areas; and
g. At least one example calculation which shows the
				  methodology used to determine the amount of shielding required for each
				  physical condition (i.e., primary and secondary or leakage barriers, restricted
				  and unrestricted areas, small angle scatter, entry doors and maze) and
				  shielding material in the facility:
(1) If commercial software is used to generate shielding
				  requirements, also identify the software used and the version or revision date;
				  and
(2) If the software used to generate shielding requirements
				  is not in the open literature, also submit quality control sample calculations
				  to verify the result obtained with the software.
4. Neutron shielding. In addition to the requirements listed
				  in subsection 3, therapeutic radiation machine facilities that are capable of
				  operating above 10 MV shall submit shielding plans which contain, as a minimum,
				  the following additional information:
a. The structural composition, thickness, minimum density,
				  and location of all neutron shielding material;
b. Description of all assumptions that were used in neutron
				  shielding calculations, including neutron spectra as a function of energy,
				  neutron fluence rate, absorbed dose, and dose equivalent (due to neutrons) in
				  both restricted and unrestricted areas;
c. At least one example calculation which shows the
				  methodology used to determine the amount of neutron shielding required for each
				  physical condition (i.e., restricted and unrestricted areas, entry doors and
				  maze) and neutron shielding material utilized in the facility:
(1) If commercial software is used to generate shielding
				  requirements, also identify the software used and the version or revision date;
				  and
(2) If the software used to generate shielding requirements
				  is not in the open literature, also submit quality control sample calculations
				  to verify the result obtained with the software. d. The methods and
				  instrumentation that will be used to verify the adequacy of all neutron
				  shielding installed in the facility.
5. References.
a. NCRP Report 147, "Structural Shielding Design and
				  Evaluation for Medical Use of X-Rays and Gamma Rays of Energies Up to 10 MeV"
				  (2004).
b. NCRP Report 144, "Radiation Protection Design Guidelines
				  for 0.1-100 MeV Particle Accelerator Facilities" (2003).
c. NCRP Report 79, "Neutron Contamination from Medical
				  Electron Accelerators" (1984).