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)(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DHS 157 Appendix M. If any information submitted to the department becomes invalid or outdated, the department shall be immediately notified.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)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)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)(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)(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)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 20
µGy (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)(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.
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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.
DHS 157.75(5)(c)
(c) The required minimal half-value layer of the useful beam shall include the filtration contributed by all materials that are permanently between the source and the patient.
DHS 157.75(5)(d)
(d) For x-ray systems with variable filtration controls, the system shall prevent an exposure unless the appropriate filtration is in place for the kilovolts peak selected.
DHS 157.75(6)
(6)
Multiple tubes. When 2 or more radiographic tubes are controlled by one exposure switch, the tube that has been selected shall be clearly indicated prior to initiation of the exposure. The indication shall be both on an x-ray control panel and at or near the selected tube housing assembly.
DHS 157.75(7)
(7)
Mechanical support of tube head. The tube housing assembly supports shall be adjusted such that the tube housing assembly will remain stable during an exposure unless tube-housing movement is a designed function of an x-ray system.
DHS 157.75(8)(a)(a) The technique factors to be used during an exposure shall be indicated before the exposure begins. If automatic exposure controls are used, the technique factors, which are set prior to the exposure, shall be indicated.
DHS 157.75(8)(b)
(b) The requirement in par.
(a) may be met by permanent markings on equipment having fixed technique factors. Indication of technique factors shall be visible from the operator's position except in the case of spot films made by the fluoroscopist.
DHS 157.75(9)
(9)
Maintaining compliance. Diagnostic x-ray systems and their associated components used on humans and certified under the federal x-ray equipment performance standard,
21 CFR 1020, shall be maintained in compliance with applicable requirements of that standard.
DHS 157.75(10)
(10)
Locks. All position locking, holding and centering devices on x-ray system components and systems shall function as intended.
DHS 157.76
DHS 157.76 Fluoroscopic equipment. Only image-intensified or direct-digital receptor fluoroscopic equipment shall be used for fluoroscopy. Equipment for fluoroscopic imaging or for recording images from the fluoroscopic image receptor, except computed tomography x-ray systems manufactured on or after November 29, 1984, shall meet all the following requirements:
DHS 157.76(1)(a)
(a) The fluoroscopic imaging assembly shall be provided with a primary protective barrier which intercepts the entire cross section of the useful beam at any source to image distance. The x-ray tube used for fluoroscopy shall not produce x-rays unless the barrier is in position to intercept the entire useful beam. The air kerma rate due to transmission through the barrier with the attenuation block in the useful beam combined with radiation from the fluoroscopic image receptor shall not exceed 3.34 x 10
-3 percent of the entrance air kerma rate, at a distance of 10 cm from any accessible surface of the fluoroscopic imaging assembly beyond the plane of the image receptor.
DHS 157.76(1)(b)1.
1. The air kerma rate shall be measured as required under sub.
(4). The air kerma rate due to transmission through the primary barrier combined with radiation from the fluoroscopic image receptor shall be determined by measurements averaged over an area of 100 square cm with no linear dimension greater than 20 cm.
DHS 157.76(1)(b)2.
2. If the source is below the tabletop, the measurement shall be made with the input surface of the fluoroscopic imaging assembly positioned 30 cm above the tabletop. If the source is above the tabletop and the source to image distance is variable, the measurement shall be made with the end of the beam-limiting device or spacer as close to the tabletop as it can be placed, provided that it shall not be closer than 30 cm.
DHS 157.76(1)(b)3.
3. Movable grids and compression devices shall be removed from the useful beam during the measurement.
DHS 157.76(1)(b)4.
4. For all measurements, the attenuation block shall be positioned in the useful beam 10 cm from the point of measurement of entrance air kerma rate and between this point and the input surface of the fluoroscopic imaging assembly.
DHS 157.76(1)(c)
(c) Radiation therapy simulation systems shall be exempt from this requirement provided the systems are intended only for remote control operation and the manufacturer sets forth instructions for assemblers with respect to control location as part of the information required in
21 CFR 1020.30 (g).
DHS 157.76(2)(a)(a) For fluoroscopic equipment manufactured after February 25, 1978, when the angle between the image receptor and the beam axis of the x-ray beam is variable, means shall be provided to indicate when the axis of the x-ray beam is perpendicular to the plane of the image receptor. Compliance with par.
(e) 1. and
2. shall be determined with the beam axis indicated to be perpendicular to the plane of the image receptor.
DHS 157.76(2)(b)
(b) Means shall be provided to permit further limitation of the x-ray field to sizes smaller than the limits of par.
(e) 1. and
2. Beam limiting devices manufactured after May 22, 1979, and incorporated in equipment with a variable source to image distance, the capability of a visible area of greater than 300 square cm, or both, shall be provided with means for stepless adjustment of the x-ray field. Equipment with a fixed source to image distance and the capability of a visible area of no greater than 300 square cm shall be provided with either stepless adjustment of the x-ray field or with a means to further limit the x-ray field size at the plane of the image receptor to 125 square cm or less. Stepless adjustment shall, at the greatest source to image distance, provide continuous field sizes from the maximum obtainable to a field size containable in a square of 5 cm by 5 cm. This paragraph does not apply to intensified fluoroscopy units without image intensification.
DHS 157.76(2)(c)
(c) The x-ray field produced by non-image-intensified fluoroscopic equipment shall not extend beyond the entire visible area of the image receptor. Means shall be provided for stepless adjustment of field size. The minimum field size, at the greatest source to image distance, shall be containable in a square of 5 cm by 5 cm.
DHS 157.76(2)(d)
(d) For fluoroscopic equipment with inherently circular image receptors manufactured before June 10, 2006, other than radiation therapy simulation systems, all the following applies:
DHS 157.76(2)(d)1.
1. Neither the length nor the width of the x-ray field in the plane of the image receptor shall exceed that of the visible area of the image receptor by more than 3% of the source to image distance. The sum of the excess length and the excess width shall be no greater than 4% of the source to image distance.
DHS 157.76(2)(d)2.
2. For rectangular x-ray fields used with circular image receptors, the error in alignment shall be determined along the length and width dimensions of the x-ray field which pass through the center of the visible area of the image receptor.
DHS 157.76(2)(e)
(e) For fluoroscopic equipment manufactured on or after June 10, 2006, other than radiation therapy simulation systems, the maximum area of the x-ray field in the plane of the image receptor shall conform to one of the following requirements:
DHS 157.76(2)(e)1.
1. When any linear dimension of the visible area of the image receptor measured through the center of the visible area is less than or equal to 34 cm in any direction, at least 80% of the area of the x-ray field overlaps the visible area of the image receptor.
DHS 157.76(2)(e)2.
2. When any linear dimension of the visible area of the image receptor measured through the center of the visible area is greater than 34 cm in any direction, the x-ray field measured along the direction of greatest misalignment with the visible area of the image receptor does not extend beyond the edge of the visible area of the image receptor by more than 2 cm.
DHS 157.76(2)(f)
(f) For x-ray systems with inherently rectangular image receptors manufactured on or after June 10, 2006, all the following applies:
DHS 157.76(2)(f)1.
1. Neither the length nor the width of the x-ray field in the plane of the image receptor shall exceed that of the visible area of the image receptor by more than 3% of the source to image distance. The sum of the excess length and the excess width shall be no greater than 4% of the source to image distance.
DHS 157.76(2)(f)2.
2. The error in alignment shall be determined along the length and width dimensions of the x-ray field which pass through the center of the visible area of the image receptor.
DHS 157.76(2)(g)
(g) If the fluoroscopic x-ray field size is adjusted automatically as the source to image distance or image receptor size is changed, a capability may be provided for overriding the automatic adjustment in case of system failure. If it is so provided, a signal visible at the fluoroscopist's position shall indicate whenever the automatic field adjustment is overridden. Each such system failure override switch shall be clearly labeled as follows:
For X-ray Field Limitation System Failure
DHS 157.76(3)
(3)
Activation of tube. X-ray production in the fluoroscopic mode shall be controlled by a device which requires continuous pressure by the operator for the entire time of any exposure. When recording serial radiographic images from the fluoroscopic image receptor, the operator shall be able to terminate the x-ray exposure at any time, but means may be provided to permit completion of any single exposure of the series in process.
DHS 157.76(4)(a)(a) Fluoroscopic equipment manufactured before May 19, 1995 shall meet all the following requirements:
DHS 157.76(4)(a)1.
1. Equipment provided with automatic exposure rate control shall not be operable at any combination of tube potential and current that will result in an air kerma rate in excess of 88 mGy per minute (10 R/min) at the measurement point specified in par.
(e), except as specified in par.
(e) 6. DHS 157.76(4)(a)2.
2. Equipment provided without automatic exposure rate control shall not be operable at any combination of tube potential and current that will result in an air kerma rate in excess of 44 mGy per minute (5 R/min) at the measurement point specified in par.
(e), except as specified in par.
(e) 6. DHS 157.76(4)(a)3.
3. Equipment provided with both an automatic exposure rate control mode and a manual mode shall not be operable at any combination of tube potential and current that will result in an air kerma rate in excess of 88 mGy per minute (10 R/min) in either mode at the measurement point specified in par.
(e), except as specified in par.
(e) 6. DHS 157.76(4)(a)4.
4. Equipment may be modified in accordance with
21 CFR 1020.30(q) to comply with par.
(a). When the equipment is modified, it shall bear a label indicating the date of the modification and the statement:
