Chapter DHS 157

DHS 157.03(212) (212) “Medium dose-rate remote afterloader” or “MDR” means a device that delivers a dose rate of greater than 2 gray (200 rads) but less than 12 gray (1200 rads) per hour at the point or surface where the dose is prescribed.

DHS 157.03(213) (213) “Megavolt” or “MV” means the energy equal to that acquired by a particle with one electron charge in passing through a potential difference of one million volts in a vacuum.

DHS 157.03 Note Note: The current convention is to use MV to designate photons and MeV to designate electrons.

DHS 157.03(214) (214) “Member of the public” means an individual in a controlled or unrestricted area. However, an individual is not a member of the public during any period in which the individual receives an occupational dose.

DHS 157.03(215) (215) “Minor” means an individual less than 18 years of age.

DHS 157.03(215m) (215m) “Mobile device” means a piece of equipment containing licensed radioactive material that is either mounted on wheels or casters, or otherwise equipped for moving without a need for disassembly or dismounting; or designed to be hand carried. “Mobile device” does not include stationary equipment installed in a fixed location.

DHS 157.03(216) (216) “Mobile medical service supplier” means a mobile service that carries or receives radioactive materials for medical use at a client’s address.

DHS 157.03(217) (217) “Mobile x-ray equipment” means x-ray equipment mounted on a permanent base with wheels or casters for moving while completely assembled.

DHS 157.03(218) (218) “Moderator” means a material that decreases the energy of neutrons.

DHS 157.03(219) (219) “Monitoring” means the measurement of radiation, radioactive material concentrations, surface area activities or quantities of radioactive material and the use of the results of these measurements to evaluate potential exposures and doses.

DHS 157.03(219m) (219m) “Movement control center” means an operations center that is remote from transport activity and that maintains position information on the movement of radioactive material, receives reports of attempted attacks or thefts, provides a means for reporting these and other problems to appropriate agencies, and requests and coordinates appropriate aid.

DHS 157.03(220) (220) “Moving beam radiation therapy” means radiation therapy with any planned displacement of radiation field or patient relative to each other or with any planned change of absorbed dose distribution. It includes arc, skip, conformal, intensity modulation and rotational therapy.

DHS 157.03(221) (221) “Multiple tomogram system” means a computed tomography x-ray system that obtains x-ray transmission data simultaneously during a single scan to produce more than one tomogram image.

DHS 157.03(221m) (221m) “Nationally tracked source” means a sealed source containing a quantity equal to or greater than category 1 or category 2 thresholds of any radioactive material listed in ch. DHS 157 Appendix T. In this context a sealed source is defined as radioactive material that is sealed in a capsule or closely bonded, in a solid form and which is not exempt from regulatory control. It does not mean material encapsulated solely for disposal, or nuclear material contained in any fuel assembly, subassembly, fuel rod, or fuel pellet. Category 1 nationally tracked sources are those containing radioactive material at a quantity equal to or greater than the category1 threshold. Category 2 nationally tracked sources are those containing radioactive material at a quantity equal to or greater than the category 2 threshold but less than the category 1 threshold.

DHS 157.03 Note Note: Chapter DHS 157 Appendix T is used to determine the category 1 and category 2 thresholds for a nationally tracked source. The category 1 and category 2 thresholds in ch. DHS 157 Appendix T and ch. DHS 157 Appendix U are not interchangeable.

DHS 157.03(222) (222) “NARM” means any naturally occurring or accelerator-produced radioactive material.

DHS 157.03(223) (223) “Natural radioactivity” means radioactivity of naturally occurring nuclides.

DHS 157.03(224) (224) “Natural thorium” means thorium with the naturally occurring distribution of thorium isotopes, which is essentially 100 weight percent thorium-232.

DHS 157.03(225) (225) “Natural uranium” means uranium with the naturally occurring distribution of uranium isotopes, which is approximately 0.711 weight percent uranium-235, and the remainder by weight essentially uranium-238.

DHS 157.03(226) (226) “Negative pressure respirator — tight fitting” means a respirator in which the air pressure inside the facepiece is negative during inhalation with respect to the ambient air pressure outside the respirator.

DHS 157.03(227) (227) “Neutron absorber” means a material that absorbs neutrons emitted from radioactive material.

DHS 157.03(228) (228) “Noble gas” means a chemically inert gas that does not combine with other elements.

DHS 157.03(228m) (228m) “No-later-than arrival time” means the date and time that the shipping licensee and receiving licensee have established as the time at which an investigation will be initiated if the shipment has not arrived at the receiving facility. The no-later-than arrival time may not be more than 6 hours after the estimated arrival time for shipments of category 2 quantities of radioactive material.

DHS 157.03(229) (229) “Nominal tomographic section thickness” means the full width at half-maximum of the sensitivity profile taken at the center of the cross-sectional volume over which x-ray transmission data are collected.

DHS 157.03(230) (230) “Nominal treatment distance” means:

DHS 157.03(230)(a) (a) For electron irradiation, the distance from the scattering foil, virtual source or exit window of the electron beam to the entrance surface of the irradiated object along the central axis of the useful beam.

DHS 157.03(230)(b) (b) For x-ray irradiation, the virtual source or target to isocenter distance along the central axis of the useful beam. For non-isocentric equipment, this distance shall be that specified by the manufacturer.

DHS 157.03(230m) (230m) “Non-fixed contamination” means contamination that can be removed from a surface during normal conditions of transport.

DHS 157.03(231) (231) “Nonstochastic effect” or “deterministic effect” means health effects, the severity of which varies with the dose and for which a threshold is believed to exist. Radiation-induced cataract formation is an example of a nonstochastic effect.

DHS 157.03(232) (232) “Normal form radioactive material” means radioactive material that has not been demonstrated to qualify as special form radioactive material.

DHS 157.03(233) (233) “Notice of violation” means a written notice provided in response to an alleged infraction of ss. 254.31 to 254.45, Stats., this chapter, the conditions of a license or an order issued by the department.

DHS 157.03(234) (234) “NRC” means the U.S. nuclear regulatory commission.

DHS 157.03(235) (235) “Nuclear waste” means a quantity of source, byproduct or special nuclear material required to be in NRC-approved specification packaging while transported to, through or across a state boundary to a disposal site, or to a collection point for transport to a disposal site.

DHS 157.03(235m) (235m) “Open-beam x-ray equipment” means an open-beam x-ray system in which the beam path could be entered by any part of the body at any time.

DHS 157.03(236) (236) “Optically stimulated luminescent dosimeter” or “OSL” means a dosimeter containing a crystalline solid for measuring radiation dose plus filters to help characterize the type of radiation encountered.

DHS 157.03 Note Note: When exposed to the appropriate energy of light, exposed optically stimulated luminescent crystals give off light proportional to the energy received from the radiation.

DHS 157.03(237) (237) “Occupational dose” means the dose received by an individual in the course of employment in which the individual’s assigned duties involve exposure to radiation, or to radioactive material from licensed and unlicensed sources of radiation, whether in the possession of the licensee, registrant or other person. Occupational dose does not include dose received from background radiation, from any medical administration the individual has received, from exposure to individuals administered radioactive material and released under s. DHS 157.62 (8), from voluntary participation in medical research programs or as a member of the public.

DHS 157.03(238) (238) “Offshore platform radiography” means industrial radiography conducted from a platform over a body of water.

DHS 157.03(239) (239) “Offsite response organization” means the non-licensee offsite organizations that may be needed to respond to an emergency, including local fire, police, ambulance and hospital services.

DHS 157.03(239m) (239m) “Ophthalmic physicist” means an individual who meets all of the following qualifications:

DHS 157.03(239m)(a) (a) Meets the requirements in ss. DHS 157.61 (11) and 157.65 (6m) (a) 2.

DHS 157.03(239m)(b) (b) Is identified as an ophthalmic physicist on a specific medical use license, or other equivalent permit or license issued by the department, the NRC or an agreement state, or broad scope medical use licensee.

DHS 157.03(240) (240) “Output” means the exposure rate, dose rate or a quantity related in a known manner to these rates from a brachytherapy source or a teletherapy, remote afterloader or gamma stereotactic radiosurgery unit for a specified set of exposure conditions.

DHS 157.03(241) (241) “Package” means the packaging together with its radioactive contents as presented for transport.

DHS 157.03(242) (242) “Packaging” means the assembly of components necessary to ensure compliance with the packaging requirements of 49 CFR Part 173, Subpart I. It may consist of one or more receptacles, absorbent materials, spacing structures, thermal insulation, radiation shielding and devices for cooling or absorbing mechanical shocks. The vehicle, tie-down system and auxiliary equipment may be designated as part of the packaging.

DHS 157.03(243) (243) “Panoramic dry-source-storage irradiator” means a device in which the irradiations occur in air in areas potentially accessible to personnel and in which the sources are stored in shields made of solid materials. The term includes beam-type dry-source-storage devices in which only a narrow beam of radiation is produced.

DHS 157.03(244) (244) “Panoramic irradiator” means a device in which the irradiations are performed in air in areas potentially accessible to personnel. The term includes beam-type devices.

DHS 157.03(245) (245) “Panoramic wet-source-storage irradiator” means a device in which the irradiations occur in air in areas potentially accessible to personnel and in which the sources are stored under water in a storage pool.

DHS 157.03(246) (246) “Pass box” means a box with openings on each side that is placed in a wall between an x-ray room and a darkroom allowing transfer of film holders between the 2 rooms.

DHS 157.03(247) (247) “Patient” means an individual or animal subjected to healing arts examination, diagnosis or treatment.

DHS 157.03(247m) (247m) “PACS” means picture archiving and communication system.

DHS 157.03(248) (248) “Periodic quality control check” means a procedure that is performed to ensure that a previous calibration continues to be valid.

DHS 157.03(249) (249) “Permanent radiographic installation” means an enclosed shielded room, cell or vault, not located at a temporary jobsite, in which radiography is performed.

DHS 157.03(250) (250) “Person” means any individual, corporation, partnership, firm, association, trust, estate, public or private institution, group, agency, political subdivision of this state, any other state or political subdivision or agency thereof and any legal successor, representative, agent or agency of the foregoing, but does not include federal government agencies or Indian tribes or bands.

DHS 157.03(251) (251) “Person in control” means the individual directly responsible for safe operation of the radiation installation.

DHS 157.03(252) (252) “Personal supervision” means guidance and instruction by the supervisor who is physically present at the jobsite and watching the performance of the operation in such proximity that contact may be maintained and immediate assistance given as required.

DHS 157.03(252g) (252g) “Personnel dosimeter”means a dosimeter assigned to an individual.

DHS 157.03(252r) (252r) “Personnel security screening system” means any x-ray equipment used on humans for security evaluation.

DHS 157.03(253) (253) “Phantom” means a volume of material behaving in a manner similar to tissue with respect to the attenuation and scattering of radiation.

DHS 157.03 Note Note: This requires that both the atomic number (Z) and the density of the material be similar to that of tissue.

DHS 157.03(254) (254) “Pharmacist” means an individual licensed under ch. 450, Stats., to practice pharmacy.

DHS 157.03(255) (255) “Physician” means a medical doctor or doctor of osteopathy licensed under ch. 448, Stats., to prescribe drugs in the practice of medicine.

DHS 157.03(256) (256) “Picture element” means an elemental area of a tomogram.

DHS 157.03(257) (257) “Planned special exposure” means an infrequent exposure to radiation, separate from and in addition to the annual occupational dose limits, that requires a licensee or registrant to calculate the dose to be received by individuals prior to initiation of the planned task, as required under s. DHS 157.22 (6).

DHS 157.03(258) (258) “Pocket dosimeter” means a type of individual monitoring device that allows the user to view the accumulated radiation exposure received as recorded by the device.

DHS 157.03(259) (259) “Podiatrist” means an individual licensed under ch. 448, Stats., to practice podiatry.

DHS 157.03(260) (260) “Pool irradiator” means any irradiator where the sources are stored or used in a pool of water including panoramic wet-source-storage irradiators and underwater irradiators.

DHS 157.03(261) (261) “Portable x-ray equipment” means x-ray equipment designed to be hand-carried.

DHS 157.03(262) (262) “Position indicating device” or “PID” means a device on dental x-ray equipment used to indicate the beam position and to establish a definite source-surface distance from the skin.

DHS 157.03 Note Note: A position indicating device may or may not incorporate or serve as a beam-limiting device.

DHS 157.03(263) (263) “Positive beam limitation” or “PBL” means the automatic or semi-automatic adjustment of an x-ray beam to the size of the selected image receptor, whereby exposures cannot be made without such adjustment.

DHS 157.03(264) (264) “Positive pressure respirator” means a respirator in which the pressure inside the respiratory inlet covering exceeds the ambient air pressure outside the respirator.

DHS 157.03(264m) (264m) “Positron emission tomography/computed tomography” or “PET/CT” means a dual modality imaging assembly comprised of two distinct components, one using radioactive material for imaging and the other using an x-ray source.

DHS 157.03(264r) (264r) “Positron emission tomography radionuclide production facility” or “PET facility” means a facility operating a cyclotron or accelerator for the purpose of producing PET radionuclides within a consortium for noncommercial distribution among its associated members for medical use.

DHS 157.03(265) (265) “Powered air-purifying respirator” or “PAPR” means an air-purifying respirator that uses a blower to force the ambient air through air-purifying elements to the inlet covering.

DHS 157.03(266) (266) “Practical examination” means a demonstration through application of the safety rules and principles in industrial radiography including use of all procedures and equipment to be used by radiographic personnel.

DHS 157.03(267) (267) “Preceptor” means an individual who provides, directs or verifies training and experience required for an individual to become an authorized user, an authorized medical physicist, an authorized nuclear pharmacist, a radiation safety officer for medical use, or an associate radiation safety officer.

DHS 157.03(268) (268) “Prescribed dosage” means the specified activity or a range of activities of a drug containing radioactive material as documented by any of the following means:

DHS 157.03(268)(a) (a) In a written directive or prescription.

DHS 157.03(268)(b) (b) Under directions of the authorized user for procedures not requiring a written directive.

DHS 157.03(269) (269) “Prescribed dose” means any of the following:

DHS 157.03(269)(a) (a) For gamma stereotactic radiosurgery, the total dose as documented in the written directive.

DHS 157.03(269)(b) (b) For teletherapy, the total dose and dose per fraction as documented in the written directive.

DHS 157.03(269)(c) (c) For brachytherapy, either the total source strength and exposure time or the total dose, as documented in the written directive.

DHS 157.03(269)(d) (d) For remote afterloaders, the total dose and dose per fraction as documented in the written directive.

DHS 157.03(270) (270) “Pressure demand respirator” means a positive pressure atmosphere-supplying respirator that admits breathing air to the facepiece when the positive pressure is reduced inside the facepiece by inhalation.

DHS 157.03(271) (271) “Primary dose monitoring system” means a system which will monitor the useful beam during irradiation and which will terminate irradiation when a pre-selected number of dose monitor units have been delivered.

DHS 157.03(272) (272) “Primary protective barrier” means the material, excluding filters, placed in the useful beam.

DHS 157.03(273) (273) “Principal activities” means activities authorized by the license that are essential to achieving the purpose for which the license was issued or amended. “Principal activities” do not include storage during which no licensed material is accessed for use or disposal and activities incidental to decontamination or decommissioning.