Chapter DHS 157

DHS 157.73 History History: CR 01-108: cr. Register July 2002 No. 559, eff. — see Note at the start of the chapter; CR 06-021: am. (15) (c), (22) (k) and (m) Register October 2006 No. 610, eff. 11-1-06; correction in (15) (d), (16) (c) made under s. 35.17, Stats., Register January 2018 No. 745; CR 22-015: am. (12) (d) (intro.), (e), (g), (14) (a), (c), (18) (b), (22) (e) Register June 2023 No. 810, eff. 7-1-23.

subch. VIII of ch. DHS 157 Subchapter VIII — X-ray Device Requirements

DHS 157.74 DHS 157.74 Administrative requirements.

DHS 157.74(1) (1) General. The registrant shall be responsible for directing the operation of the x-ray systems under their administrative control. The registrant or the registrant’s agent shall ensure the requirements of this section are met. An x-ray system shall meet the provisions of this subchapter to be operated for diagnostic or screening purposes. All images, hard copy or electronic, shall be interpreted by a licensed practitioner for the patient record.

DHS 157.74(2) (2) Radiation safety requirements.

DHS 157.74(2)(a) (a) Each individual who operates x-ray equipment shall be instructed in the safe operating procedures for each specific device and be competent in the safe use of the equipment as determined by the registrant.

DHS 157.74(2)(b) (b) A chart shall be available near the control panel of a diagnostic x-ray system that specifies, for all examinations performed with that system, all of the following information:

DHS 157.74(2)(b)1. 1. Patient’s body part to be examined and anatomical size, body part thickness or, for pediatrics, age versus technique factors to be utilized.

DHS 157.74(2)(b)2. 2. Type and size of the image receptor or film-screen combination to be used.

DHS 157.74(2)(b)3. 3. Type and focal distance of the grid to be used, if any.

DHS 157.74(2)(b)4. 4. Except for dental intra-oral radiography, source to image receptor distance to be used.

DHS 157.74(2)(b)5. 5. Type and location of placement of patient shielding to be used.

DHS 157.74 Note Note: This chart may be electronic in the form of pre-programmed controls.

DHS 157.74(2)(c) (c) The registrant of a facility shall create and make available to x-ray operators written safety procedures, including patient holding procedures and any restrictions of the operating technique required for the safe operation of the particular x-ray system. The operator shall be able to demonstrate familiarity with these procedures.

DHS 157.74(2)(d) (d) Only the staff, ancillary personnel or other persons required for the medical procedure or training may be in the room during the radiographic exposure. Other than the patient, the following applies to all persons in the room:

DHS 157.74(2)(d)1. 1. All persons shall be positioned such that no part of the body will be struck by the useful beam unless protected by not less than 0.5 millimeter lead equivalent material. If the hands must be in the beam and unprotected, a ring badge on the hand in the beam shall be worn unless contraindicated by the clinical procedure.

DHS 157.74(2)(d)2. 2. All persons, including any patients who cannot be removed from the room, shall be protected from the direct scatter radiation by whole body protective barriers of not less than 0.25 millimeter lead equivalent material or shall be so positioned that all parts of the person’s body are at least 2 meters from all of the following:

DHS 157.74(2)(d)2.a. a. The tube head.

DHS 157.74(2)(d)2.b. b. The direct beam.

DHS 157.74(2)(d)2.c. c. The nearest part of the examined patient’s body being struck by the useful beam.

DHS 157.74(2)(d)3. 3. Operators of c-arm configuration units which do not operate at a tube current in excess of 0.2 mA are exempt from the requirement to wear a leaded apron, provided the operator wears a personal dosimeter as required under s. DHS 157.25 (2).

DHS 157.74(2)(f) (f) Persons may not be exposed to the useful beam except for healing arts purposes and unless such exposure has been authorized by a licensed practitioner of the healing arts or a Wisconsin licensed physical therapist. Deliberate exposure for any of the following purposes is prohibited:

DHS 157.74(2)(f)1. 1. Exposure of a person for training, demonstration or other non-healing arts purpose, except as authorized by the department.

DHS 157.74(2)(f)2. 2. Exposure of a person for healing arts screening, except as authorized by the department.

DHS 157.74 Note Note: The procedure for requesting permission to conduct screening x-ray examination is in ch. DHS 157 Appendix M.

DHS 157.74(2)(fm) (fm) Registrants may conduct medical research that includes exposure to radiation and are exempt from obtaining individual project authorization from the department under all the following conditions:

DHS 157.74(2)(fm)1. 1. The use of radiation-generating equipment to conduct research on human beings has been approved by an institutional review board as required by 45 CFR 46 and 21 CFR 56.

DHS 157.74(2)(fm)2. 2. The institutional review board’s review of the research project includes a radiation safety review by qualified radiation personnel.

DHS 157.74(2)(fm)3. 3. All research projects using radiation need to be identified and documentation shall be made available to the department upon request.

DHS 157.74(2)(fm)4. 4. The number of facilities and exam types used by the registrant are reported to the department annually.

DHS 157.74(2)(fm)5. 5. Nothing in this paragraph relieves registrants from complying with the other requirements of this subchapter.

DHS 157.74(2)(g) (g) When a patient or film must be provided with additional support during a radiation exposure, all of the following applies:

DHS 157.74(2)(g)1. 1. The human holder shall be instructed in personal radiation safety and protected as required by subd. 2. Written safety procedures are required.

DHS 157.74(2)(g)2. 2. In those cases where the patient must hold the film, any portion of the body other than the area of clinical interest struck by the useful beam shall be protected by not less than 0.5 millimeter lead equivalent material.

DHS 157.74(2)(g)3. 3. Each facility shall have leaded shielding garments and devices available in sufficient numbers to provide protection to all personnel who are involved with x-ray operations and who are otherwise not shielded.

DHS 157.74(2)(g)4. 4. Leaded shielding garments and devices shall be fluoroscopically or radiographically inspected at least every 2 years for defects and replaced if defective.

DHS 157.74(2)(g)5. 5. If visual inspection reveals possible defects, radiographic or fluoroscopic inspections shall be performed.

DHS 157.74 Note Note: Leaded shielding garments and devices include aprons, gloves, vests, skirts, thyroid shields and gonadal shields.

DHS 157.74(2)(h) (h) Procedures and auxiliary equipment designed to minimize patient and personnel exposure commensurate with the needed diagnostic information shall be utilized, as follows:

DHS 157.74(2)(h)1. 1. The speed of the image receptor used shall be of a speed consistent with the diagnostic objective of the examinations. Film cassettes without intensifying screens may not be used for any routine diagnostic radiological imaging, with the exception of veterinary radiography and standard film packets for intra-oral use in dental radiography.

DHS 157.74(2)(h)2. 2. The radiation exposure to the patient shall be the minimum exposure required to produce images of good diagnostic quality.

DHS 157.74(2)(h)3. 3. An x-ray system may not be utilized in a procedure where the source to patient distance is less than 30 centimeters, except for a veterinary system, bone density unit or a unit granted an exemption by the US food and drug administration.

DHS 157.74(2)(h)4. 4. If grids are used between the patient and the image receptor to decrease scatter to the film and improve contrast, the grid shall meet all of the following requirements:

DHS 157.74(2)(h)4.a. a. Be positioned with tube side facing the in right direction, and grid centered to the central ray.

DHS 157.74(2)(h)4.b. b. Be of the proper focal distance for the SIDs being used. Grids shall be of the proper ratio to adequately reduce scatter for the procedure being performed.

DHS 157.74(2)(h)4.c. c. Anti-scatter grids or an appropriate air gap technique to reduce scatter to the image receptor shall be used for all x-ray examinations of the human torso utilizing stationary x-ray equipment for patients 12 years of age or older.

DHS 157.74(2)(i) (i) All persons associated with the operation of an x-ray system are subject to the requirements of s. DHS 157.22 (1), (5), (7) and (8).

DHS 157.74(2)(j) (j) A person proposing to conduct a healing arts screening program may not initiate a program without the department’s prior approval. When requesting approval, the person shall submit the information outlined in ch. DHS 157 Appendix M. If any information submitted to the department becomes invalid or outdated, the department shall be immediately notified.

DHS 157.74(2)(k) (k) All facilities performing mammography shall meet the requirements of 21 CFR 900, US food and drug administration, Mammography Quality Standards Act.

DHS 157.74(2)(L) (L) A registrant that uses two or more therapeutic radiation machines for human use shall establish a radiation safety committee consisting of at least three members to oversee the use of all therapeutic radiation machines. The committee shall include an operator authorized by the registrant, a representative of the institution’s management, and the radiation safety officer. If the institution has a radiation safety committee established under s. DHS 157.61 (1) (e), this committee may be designated to oversee the use of all therapeutic radiation machines, if an operator authorized by the registrant is appointed to this committee.

DHS 157.74(2)(m) (m) Each individual operating x-ray equipment for diagnostic medical purposes on humans shall have a current radiography license or limited x-ray machine operators permit from the State of Wisconsin.

DHS 157.74(3) (3) X-ray image processing equipment and processing procedures.

DHS 157.74(3)(a) (a) Film.

DHS 157.74(3)(a)1. 1. Each installation using a radiographic x-ray system for human diagnosis or screening and using analog image receptors shall have available suitable equipment for handling and processing radiographic film according to the film and chemistry manufacturer’s instructions.

DHS 157.74(3)(a)2. 2. Quality control and maintenance procedures shall be performed on a regular schedule according to the device manufacturer’s recommendations.

DHS 157.74(3)(a)3. 3. X-ray film processing control tests shall be performed and analyzed on days when human patient films are being processed and prior to the processing of the first films of the day, except dental and podiatry facilities. If analysis shows that the image quality has declined, corrective action shall be taken prior to processing patient films.

DHS 157.74(3)(a)4. 4. X-ray film processors in dental and podiatry facilities shall be tested at least once a week.

DHS 157.74(3)(b) (b) Digital imaging systems.

DHS 157.74(3)(b)1. 1. Each installation using a digital radiographic x-ray system for human diagnosis or screening shall have available suitable equipment for handling and processing the radiographic digital image according to the manufacturer’s instructions.

DHS 157.74(3)(b)2. 2. Quality control and maintenance procedures shall be performed on a regular schedule according to the device manufacturer’s recommendations or procedures approved by the department. If analysis shows that the system test results fall outside the device manufacturer’s recommended limits corrective action shall be taken prior to performing patient examinations.

DHS 157.74(4) (4) Other requirements.

DHS 157.74(4)(a) (a) Pass boxes, if provided, shall be constructed to exclude light from the darkroom when cassettes are placed in or removed from the boxes and shall incorporate adequate shielding from stray radiation to prevent exposure of undeveloped film.

DHS 157.74(4)(b) (b) The darkroom shall be light tight with proper safelights so that any film type in use exposed in a cassette to x-radiation sufficient to produce an optical density from 1 to 2 when processed may not suffer an increase in density greater than 0.1, or 0.05 for mammography, when exposed in the darkroom for 2 minutes with all safelights on. This test shall be performed at least once every 6 months. If used, daylight film handling boxes shall preclude fogging of the film. Darkrooms typically used by more than one person shall be provided a method to prevent accidental entry while undeveloped films are being handled or processed.

DHS 157.74(4)(c) (c) Film shall be stored according to the manufacturer’s requirements and shall be protected from exposure to stray radiation. Film in open packages shall be stored in a light tight container.

DHS 157.74(4)(d) (d) Film cassettes and intensifying screens shall be inspected periodically and shall be cleaned and replaced as necessary and consistent with the manufacturer’s instructions to best assure radiographs of good diagnostic quality.

DHS 157.74(4)(e) (e) Outdated x-ray film may not be used for diagnostic radiographs.

DHS 157.74(4)(f) (f) Film developing solutions shall be prepared using instructions given by the manufacturer and maintained in strength by replenishment or renewal so that full development is accomplished within the time specified by the manufacturer.

DHS 157.74(5) (5) Hospitals.

DHS 157.74(5)(a) (a) Hospitals using registered radiation machines shall comply with all of the following:

DHS 157.74(5)(a)1. 1. Keep the radiological service free of hazards for patients and personnel.

DHS 157.74(5)(a)2. 2. Maintain safety precautions against fire and explosion hazards, electrical hazards, and radiation hazards.

DHS 157.74(5)(a)3. 3. Inspect registered facilities and equipment at least once every 2 years for compliance with this chapter. This inspection shall be completed by one of the following:

DHS 157.74(5)(a)3.a. a. A qualified radiation physicist.

DHS 157.74(5)(a)3.b. b. A designee of a qualified radiation physicist.

DHS 157.74(5)(a)3.c. c. The department as outlined in s. DHS 157.89.

DHS 157.74(5)(a)4. 4. Correct radiation hazards identified by a qualified radiation physicist or their designee within 30 days of identification.

DHS 157.74 History History: CR 01-108: cr. Register July 2002 No. 559, eff. 8-1-02; CR 06-021: am. (2) (b) (intro.), (g) 3., 4., (3) (c) and (4) (b), cr. (2) (d) 3. and (g) 5. Register October 2006 No. 610, eff. 11-1-06; CR 09-062: am. (2) (g) 4. and (3) (title), cr. (2) (L), (3) (a) (title) and (b), renum. (3) (a) to (d) to be (3) (a) 1. to 4. Register April 2010 No. 652, eff. 5-1-10; CR 16-078: am. (2) (b) 2., (d) 3., (f) (intro.), (h) 1., 4. c., cr. (2) (m), am. (3) (b) 2., (4) (b) Register January 2018 No. 745, eff. 2-1-18; correction in (2) (j) made under s. 35.17, Stats., Register January 2018 No. 745; CR 22-015: am.(2) (f) 1., cr. (2) (fm), (5), Register June 2023 No. 810, eff. 7-1-23.

DHS 157.75 DHS 157.75 General requirements for all diagnostic x-ray systems. Diagnostic x-ray systems shall meet all the following requirements:

DHS 157.75(1) (1) Warning label. The control panel containing the main power switch shall bear the following warning statement, legible and accessible to view: “WARNING: This x-ray unit may be dangerous to patient and operator unless safe exposure factors and operating instructions are observed.”

DHS 157.75(2) (2) Battery charge indicator. On battery-powered x-ray generators, visual means shall be provided on the control panel to indicate whether the battery is in a state of charge adequate for proper operation.

DHS 157.75(3) (3) Leakage radiation from the diagnostic source assembly. The leakage radiation from the diagnostic source assembly measured at a distance of one meter in any direction from the source may not exceed one mGy (115 milliroentgens) in one hour when an x-ray tube is operated at its leakage technique factors. Compliance shall be determined by measurements averaged over an area of 100 square centimeters with no linear dimension greater than 20 centimeters. Leakage technique factors may be any of the following:

DHS 157.75(3)(a) (a) For diagnostic source assemblies intended for capacitor energy storage equipment, the maximum-rated peak tube potential and the maximum-rated number of exposures in an hour for operation at the maximum-rated peak tube potential with the quantity of charge per exposure being 10 millicoulombs, which is 10 mAs, or the minimum obtainable from the unit, whichever is larger.

DHS 157.75(3)(b) (b) For diagnostic source assemblies intended for field emission equipment rated for pulsed operation, the maximum-rated peak tube potential and the maximum-rated number of x-ray pulses in an hour for operation at the maximum-rated peak tube potential.

DHS 157.75(3)(c) (c) For all other diagnostic source assemblies, the maximum-rated peak tube potential and the maximum-rated continuous tube current for the maximum-rated peak tube potential.

DHS 157.75(4) (4) Radiation from components other than the diagnostic source assembly. The radiation emitted by a component other than the diagnostic source assembly may not exceed 20mGy (2.15 milliroentgens) in one hour at 5 centimeters from any accessible surface of the component when it is operated in an assembled x-ray system under any conditions for which it was designed. Compliance shall be determined by measurements averaged over an area of 100 square centimeters with no linear dimension greater than 20 centimeters.

DHS 157.75(5) (5) Beam quality.

DHS 157.75(5)(a) (a) The half-value layer of the useful beam for a given x-ray tube potential may not be less than the values shown in Table DHS 157.75. If it is necessary to determine the half-value layer at an x-ray tube potential that is not listed in Table DHS 157.75, linear interpolation or extrapolation may be made.

- See PDF for table

DHS 157.75(5)(b) (b) For x-ray systems using capacitor discharge to provide power to an x-ray tube, half-value layer shall be determined with the system fully charged and a setting of 10 mAs for each exposure.