Pennsylvania Code › Title 25 - ENVIRONMENTAL PROTECTION › Part I - Department of Environmental Protection › Subpart D - Environmental Health and Safety › Article V - Radiological Health › Chapter 221 - X-RAYS IN THE HEALING ARTS › DIAGNOSTIC INSTALLATIONS GENERAL REQUIREMENTS › Section 221.36a - Limitation of useful beam of fluoroscopic equipment

Current through Register Vol. 54, No. 28, July 13, 2024
(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 receptor distance.
(b) The X-ray tube used for fluoroscopy may
						not produce X-rays unless a barrier is in position to intercept the useful beam
						and the imaging device is in place and operable.
(c) A means shall be provided for stepless
						(continuous) adjustment of the field size.
(d) The minimum field size at the greatest
						source to image receptor distance shall be containable in a square of 5
						centimeters by 5 centimeters unless otherwise provided in
						21 CFR
						1020.32(b) (relating to
						fluoroscopic equipment).
(e)
						Equipment may not be operated at a source to skin distance less than 30
						centimeters or as required under
						21 CFR
						1020.32(g).
(f) The width of the X-ray field in the plane
						of the image receptor may not exceed that of the visible area of the image
						receptor by more than 3% of the source to image receptor distance. The sum of
						the excess length and the excess width may not be greater than 4% of the source
						to image receptor distance.
(g) For
						rectangular X-ray fields used with a circular image receptor, the error in
						alignment shall be determined along the length and width dimensions of the
						X-ray field which passes through the center of the visible area of the image
						receptor.
(h) Compliance with
						subsections (a)-(g) shall be determined with the beam axis perpendicular to the
						plane of the image receptor.
(i)
						Spot-film devices shall meet the following additional requirements:
(1) A means shall be provided between the
						source and the patient for adjustment of the X-ray field size to the size of
						the portion of film which has been selected on the spot-film
						selector.
(2) The adjustments shall
						be automatically accomplished except when the X-ray field size in the plane of
						the film is smaller than that of the film.
(3) The total misalignment of the edges of
						the X-ray field with the respective edges of the selected portion of the image
						receptor along the length or width dimensions of the X-ray field in the plane
						of the image receptor may not exceed 3% of the source-to image receptor when
						adjusted for full coverage of the selected portion of the image
						receptor.
(4) The sum, without
						regard to sign, of the misalignment along any two orthogonal dimensions, may
						not exceed 4% of the source to image receptor distance.
(5) The center of the X-ray field in the
						plane of the film shall be aligned with the center of the film within 2% of the
						source to image receptor distance.