DHS 157.76(4)(c)1.1. Equipped with automatic exposure rate control if operable at any combination of tube potential and current that results in an air kerma rate greater than 44 mGy per minute (5 R/min) at the measurement point specified in this subsection. Provision for manual selection of technique factors may be provided.

DHS 157.76(4)(c)2.2. 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)

DHS 157.76(4)(d)1.1. For equipment manufactured prior to June 10, 2006, during the recording of images from a fluoroscopic image receptor using photographic film or a video camera when the x-ray source is operated in a pulsed mode.

DHS 157.76(4)(d)2.2. For equipment manufactured on or after June 10, 2006, during the recording of images from the fluoroscopic image receptor for the purpose of providing the user with a recorded image after termination of exposure. Such recording does not include images resulting from a last image-hold feature that are not recorded.

DHS 157.76(4)(d)3.3. When a mode of operation has an optional high-level control and the control is activated, in which case the equipment shall not be operable at any combination of tube potential and current that will result in an air kerma rate in excess of 176 mGy per minute (20 R/min) at the measurement point specified par. (e). Special means of activation of high-level controls shall be required. The high-level control shall be operable only when continuous manual activation is provided by the operator. A continuous signal audible to the fluoroscopist shall indicate that the high-level control is being employed.

DHS 157.76(4)(e)1.1. If the source is below the x-ray table, the air kerma rate shall be measured at 1 cm above the tabletop or cradle.

DHS 157.76(4)(e)2.2. If the source is above the x-ray table, the air kerma rate shall be measured at 30 cm above the tabletop with the end of the beam-limiting device or spacer positioned as closely as possible to the point of measurement.

DHS 157.76(4)(e)3.3. In a C-arm type of fluoroscope, the air kerma rate shall be measured at 30 cm from the input surface of the fluoroscopic imaging assembly, with the source positioned at any available source to image distance, provided that the end of the beam limiting device or spacer is no closer than 30 cm from the input surface of the fluoroscopic imaging assembly.

DHS 157.76(4)(e)4.4. In a C-arm type of fluoroscope having an source to image distance less than 45 cm, the air kerma rate shall be measured at the minimum source to skin distance.

DHS 157.76(4)(e)5.5. In a lateral type of fluoroscope, the air kerma rate shall be measured at a point 15 cm from the centerline of the x-ray table and in the direction of the x-ray source with the end of the beam limiting device or spacer positioned as closely as possible to the point of measurement. If the tabletop is movable, it shall be positioned as closely as possible to the lateral x-ray source, with the end of the beam-limiting device or spacer no closer than 15 cm to the centerline of the x-ray table.

DHS 157.76(4)(e)6.6. Fluoroscopic radiation therapy simulation systems are exempt from this paragraph.

DHS 157.76(5)(5) Indication of potential and current. During fluoroscopy and cinefluorography, x-ray tube potential and current shall be continuously indicated. Deviation of x-ray tube potential and current from the indicated values shall not exceed the maximum deviation as stated by the manufacturer in accordance with 21 CFR 1020.30 (h) (3).

DHS 157.76(6)(a)(a) Means shall be provided to limit the source to skin distance to not less than 38 cm on stationary fluoroscopes and to not less than 30 cm on mobile and portable fluoroscopes. In addition, for fluoroscopes intended for specific surgical application that would be prohibited at the source-skin distances specified in this paragraph, provisions may be made for operation at shorter source-skin distances but in no case less than 20 cm.

DHS 157.76(6)(b)(b) For stationary, mobile, or portable C-arm fluoroscopic systems manufactured on or after June 10, 2006, having a maximum source-image receptor distance of less than 45 cm, means shall be provided to limit the source-skin distance to not less than 19 cm. Such systems shall be labeled for extremity use only. In addition, for those systems intended for specific surgical application that would be prohibited at the source-skin distances specified in this paragraph, provisions may be made for operation at shorter source-skin distances but in no case less than 10 cm.

DHS 157.76(7)(a)(a) Fluoroscopic equipment manufactured before June 10, 2006, shall be provided with means to preset the cumulative irradiation time of the fluoroscopic tube. The maximum cumulative time of the timing device shall not exceed 5 minutes without resetting. A signal audible to the fluoroscopist shall indicate the completion of any preset cumulative Irradiation time. Such signal shall continue to sound while x-rays are produced until the timing device is reset.

DHS 157.76(7)(b)(b) As an alternative to the requirements of par. (a), radiation therapy simulation systems may be provided with a means to indicate the total cumulative exposure time during which x-rays were produced, and which is capable of being reset between x-ray examinations.

DHS 157.76(7)(c)(c) For x-ray controls manufactured on or after June 10, 2006, all of the following shall be provided for each fluoroscopic tube:

DHS 157.76(7)(c)1.1. A display of the fluoroscopic irradiation time at the fluoroscopist’s working position.

DHS 157.76(7)(c)2.2. The display required in subd. 1. shall function independently of the audible signal described in par. (a) and meet all the following requirements:

DHS 157.76(7)(c)2.a.a. When the x-ray tube is activated, the fluoroscopic irradiation time in minutes and tenths of minutes shall be continuously displayed and updated at least once every 6 seconds.

DHS 157.76(7)(c)2.b.b. The fluoroscopic irradiation time shall also be displayed within 6 seconds of termination of an exposure and remain displayed until reset.

DHS 157.76(7)(c)2.c.c. Means shall be provided to reset the display to zero prior to the beginning of a new examination or procedure.

DHS 157.76(7)(c)3.3. A signal audible to the fluoroscopist shall sound for each passage of 5 minutes of fluoroscopic irradiation time during an examination or procedure. The signal shall sound until manually reset or, if automatically reset, for at least 2 seconds.

DHS 157.76(7)(d)(d) If fluoroscopic equipment is modified in accordance with 21 CFR 1020.30(q) to comply with the requirements in par. (a), it shall bear a label that states: