Connecticut Administrative Code › Title 19 - Public Health and Safety › 25d - X-Ray Devices used for Diagnosis and Therapy › Section 19-25d-4 - Fluoroscopic installations

Current through July 10, 2024
(a)
Equipment
(1) The tube housing
			 shall be of diagnostic type.
(2)
			 The target-to-panel or target-to-table top distance of equipment installed
			 before January 1, 1965, shall not be less than twelve inches, and shall not be
			 less than fifteen inches in equipment installed or reinstalled
			 thereafter.
(3) The total
			 filtration permanently in the useful beam shall not be less than two and
			 one-half millimeters aluminum equivalent. This requirement may be assumed to
			 have been met if the half-value layer is not less than two and one-half
			 millimeters aluminum at normal operating voltages.
(4) The equipment shall be so constructed
			 that the entire cross-section of the useful beam is attenuated by a primary
			 barrier. This barrier is usually the viewing device, either a conventional
			 fluoroscopic screen or an image intensification mechanism.
(A)
(i) For
			 equipment installed before January 1, 1965, the required lead equivalent of the
			 barrier shall not be less than one and one-half millimeters for one hundred
			 kvp, shall not be less than one and eight-tenths millimeters for one hundred
			 twenty-five kvp, or shall not be less than two millimeters for one hundred
			 fifty kvp.
(ii) For equipment
			 installed or reinstalled after January 1, 1965, the required lead equivalent of
			 the barrier shall not be less than two millimeters for one hundred kvp, shall
			 not be less than two and four-tenths millimeters for one hundred twenty-five
			 kvp, or shall not be less than two and seven-tenths millimeters for one hundred
			 fifty kvp.
(iii) Insofar as related
			 to the provisions of subparagraphs (A) (i) and (A) (ii) of the subdivision for
			 conventional fluoroscopes these requirements may be assumed to have been met if
			 the exposure dose rate measured at the viewing surface of the fluorescent
			 screen does not exceed fifty milliroent gens per hour with the screen in the
			 primary beam of the fluoroscope without a patient, under normal operating
			 conditions.
(B)
			 Collimators shall be provided to restrict the size of the useful beam to less
			 than the area of the barrier. For conventional fluoroscopes this requirement is
			 met if, when the adjustable diaphragm is opened to its fullest extent, an
			 unilluminated margin is left on the fluorescent screen with the screen centered
			 in the beam at a distance of thirty-five centimeters (fourteen inches) from the
			 panel or table top. The margin requirement does not apply to installations
			 where image intensifiers are used, but a protective shield shall be provided in
			 these installations so that the useful beam does not produce a radiation
			 hazard.
(C) The tube mounting and
			 the barrier shall be so linked together that, under conditions of normal use,
			 the barrier always intercepts the useful beam.
(D) Collimators and adjustable diaphragms or
			 shutters to restrict the size of the useful beam shall provide a minimum of two
			 millimeters lead-equivalent protection for one hundred kvp, two and four-tenths
			 millimeters for one hundred twenty-five kvp or two and seven-tenths millimeters
			 for one hundred fifty kvp.
(5) The exposure switch shall be of the
			 dead-man type.
(6) A manual-reset,
			 cumulative timing device shall be used which will either indicate elapsed time
			 by an audible signal or turn off the apparatus when the total exposure exceeds
			 a predetermined limit in one or a series of exposures.
(7) For routine fluoroscopy, the exposure
			 rate measured at the panel or table top should be as low as practicable and
			 shall not exceed ten roentgens per minute.
(8) Mobile fluoroscopic equipment shall meet
			 the requirements of this section where applicable, except that:
(A) In the absence of a table top, a cone or
			 spacer frame shall limit the target-to-skin distance to not less than twelve
			 inches.
(B) Image intensification
			 shall always be provided. Conventional fluoroscopic screens shall not be
			 used.
(C) It shall be impossible to
			 operate a machine when the collimating cone or diaphragm is not in
			 place.
(D) A maximum permissible
			 dose rate of ten roentgens per minute shall be measured at the minimum
			 target-to-skin distance.