Louisiana Administrative Code
Title 33 - ENVIRONMENTAL QUALITY
Part XV - Radiation Protection
Chapter 6 - X-Rays in the Healing Arts
Section XV-605 - Fluoroscopic X-Ray Systems

i. a means shall be provided to permit further limitation of the field. Beam-limiting devices manufactured after May 22, 1979, and incorporated in equipment with a variable SID and/or a visible area of greater than 300 square centimeters shall be provided with means for stepless adjustment of the X-ray field;

ii. all equipment with a fixed SID and a visible area of 300 square centimeters or less shall be provided with either stepless adjustment of the X-ray field or with means to further limit the X-ray field size at the plane of the image receptor to 125 square centimeters or less. Stepless adjustment shall provide continuous field sizes from the maximum obtainable to a field size of 5 centimeters by 5 centimeters or less;

iii. for equipment manufactured after February 25, 1978, when the angle between the image receptor and beam axis 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; and

iv. compliance shall be determined with the beam axis indicated to be perpendicular to the plane of the image receptor. For rectangular X-ray fields used with circular image reception, the error in alignment shall be determined along the length and width dimensions of the X-ray field that pass through the center of the visible area of the image receptor.

i. means shall be provided between the source and the patient for adjustment of the X-ray field size in the plane of the image receptor to the size of that portion of the image receptor that has been selected on the spot film selector. Such adjustment shall be automatically accomplished when the X-ray field size in the plane of the image receptor is greater than that of the selected portion of the image receptor. If the X-ray field size is less than that of the selected portion of the image receptor, the field size shall not open automatically to the size of the selected portion of the image receptor unless the operator has selected that mode of operation;

ii. it shall be possible to adjust the X-ray field size in the plane of the image receptor to a size smaller than the selected portion of the image receptor. The minimum field size at the greatest SID shall be equal to, or less than, 5 centimeters by 5 centimeters;

iii. the center of the X-ray field in the plane of the image receptor shall be aligned with the center of the selected portion of the image receptor to within 2 percent of the SID; and

iv. means shall be provided to reduce the X-ray field size in the plane of the image receptor to a size smaller than the selected portion of the image receptor such that:

i. For fluoroscopic equipment manufactured before June 10, 2006, other than radiation therapy simulation systems, the following applies:

ii. For fluoroscopic equipment manufactured on or after June 10, 2006, other than radiation simulation systems, the maximum area of the X-ray field in the plane of the image receptor shall conform with one of the following requirements:

i. For X-ray systems manufactured on or after June 10, 2006, the following applies:

i. Fluoroscopic equipment provided with automatic exposure rate control (AERC) shall not be operable at any combination of tube potential and current that will result in an AKR in excess of 88 mGy per minute (vice 10 R/min exposure rate) at the measurement point specified in LAC 33:XV.605.A.4.d, except as specified in LAC 33:XV.605.A.4.a.v.

ii. Equipment provided without AERC shall not be operable at any combination of tube potential and current that will result in an AKR in excess of 44 mGy per minute (vice 5 R/min exposure rate) at the measurement point specified in LAC 33:XV.605.A.4.d, except as specified in LAC 33:XV.605.A.4.a.v.

iii. Equipment provided with both an AERC mode and a manual mode shall not be operable at any combination of tube potential and current that will result in an AKR in excess of 88 mGy per minute (vice 10 R/min exposure rate) in either mode at the measurement point specified in LAC 33:XV.605.A.4.d, except as specified in LAC 33:XV.605.A.4.a.v.

iv. Equipment may be modified in accordance with this Section to comply with LAC 33:XV.605.A.4.b. When the equipment is modified, it shall bear a label indicating the date of the modification and the statement:

v. Exceptions: during recording of fluoroscopic images.

i. Equipment shall be equipped with AERC if operable at any combination of tube potential and current that results in an AKR greater than 44 mGy per minute (vice 5 R/min exposure rate) at the measurement point specified in LAC 33:XV.605.A.4.d. Provision for manual selection of technique factors may be provided.

ii. Equipment shall not be operable at any combination of tube potential and current that will result in an AKR in excess of 88 mGy per minute (vice 10 R/min exposure rate) at the measurement point specified in LAC 33:XV.605.A.4.d, except as specified in LAC 33:XV.605.A.4.b.iii.

iii. Exceptions:

i. if the source is below the X-ray table, the AKR shall be measured 1 centimeter above the tabletop or cradle;

ii. if the source is above the X-ray table, the AKR shall be measured at 30 centimeters above the tabletop with the end of the beam-limiting device or spacer positioned as closely as possible to the point of measurement;

iii. in a C-arm or L-U arm type of fluoroscope, the AKR shall be measured 30 centimeters from the input surface of the fluoroscopic imaging assembly, with the source positioned at any available SID, provided that the end of the beam-limiting device or spacer is no closer than 30 centimeters from the input surface of the fluoroscopic imaging assembly;

iv. in a C-arm type fluoroscope having an SID less than 45 cm, the AKR shall be measured at the minimum SSD; and

v. in a lateral type fluoroscope, the AKR shall be measured at a point 15 centimeters 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 centimeters to the center line of the X-ray table.

i. The AKR due to transmission through the primary protective barrier combined with radiation from the image intensifier shall be determined by measurements averaged over an area of 100 square centimeters with no linear dimension greater than 20 centimeters.

ii. If the source is below the tabletop, the measurement shall be made with the input surface of the fluoroscopic imaging assembly positioned 30 centimeters above the tabletop.

iii. If the source is above the tabletop and the SID 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 centimeters.

iv. Movable grids and compression devices shall be removed from the useful beam during the measurement.

v. For all measurements, the attenuation block shall be positioned in the useful beam 10 cm from the point of measurement of entrance AKR and between this point and the input surface of the fluoroscopic imaging assembly.

i. 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 five 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. Fluoroscopic equipment shall be modified in accordance with LAC 33:XV.605 to comply with the requirements of this Paragraph. When the equipment is modified, it shall bear a label indicating the statement; or

ii. as an alternative to the requirements of this Paragraph, radiation therapy simulation systems shall 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.

i. a display of the fluoroscopic irradiation time at the fluoroscopist's working position. This display shall function independently of the audible signal described in this Subparagraph. The following requirements apply:

ii. a signal audible to the fluoroscopist shall sound for each passage of five minutes of fluoroscopic irradiation time during an examination or procedure. The signal shall sound until manually reset or, if automatically reset, for at least two seconds.

i. For fluoroscopes with X-ray source below the X-ray table, X-ray source above the table, or of lateral type, the reference location shall be the respective locations specified in LAC 33:XV.605.A.4.d.i, ii, or v for measuring compliance with AKR limits.

ii. For C-arm fluoroscopes, the reference location shall be 15 cm from the isocenter toward the X-ray source along the beam axis. Alternatively, the reference location shall be at a point specified by the manufacturer to represent the location of the intersection of the X-ray beam with the patient's skin.

i. Shielding required under LAC 33:XV.605.A.11.a shall be maintained to the degree possible under the clinical conditions.

ii. All persons, except the patient, in the room where fluoroscopy is performed shall wear protective aprons that provide a lead equivalent shielding of at least 0.25 mm.

iii. The fluoroscopic field size shall be reduced to the minimum required for the procedure being performed (area of clinical interest).

iv. Operating and safety procedures shall reflect the above conditions, and fluoroscopy personnel shall exhibit awareness of situations requiring the use and/or nonuse of the protective drapes.

i. for systems without automatic exposure control, be made utilizing a milliamperage and kVp typical of the clinical use of the fluoroscopic system;

ii. for systems with automatic exposure control, be made utilizing sufficient attenuating material in the useful beam to produce a milliamperage and kVp typical of the clinical use of the fluoroscopic system;

i. identification of individuals who are authorized to use fluoroscopic systems for interventional purposes;

ii. a method to be used to monitor patient radiation dose during FGI;

iii. dose notification levels, as appropriate, at which the physician is notified and appropriate actions are taken for patient safety; and

iv. a review of the established protocols at intervals of no less than 12 months, and no more than 14 months, from the previous review;

i. patient identification;

ii. type and date of examination;

iii. identification of the fluoroscopic system used;

iv. peak skin dose, cumulative air kerma, or dose area product used if the information is available on the fluoroscopic system; and

v. if the peak skin dose, cumulative air kerma, or dose area product are not displayed on the fluoroscopic system, records shall include other information necessary to estimate the radiation dose to the skin in accordance with established protocol or the following, as necessary: