Applicability.(a) The provisions of this section are applicable to television receivers with cathode ray tubes manufactured subsequent to January 15, 1970.
Definitions.External surface(b) (1) means the cabinet or enclosure provided by the manufacturer as part of the receiver. If a cabinet or enclosure is not provided as part of the receiver, the external surface shall be considered to be a hypothetical cabinet, the plane surfaces of which are located at those minimum distances from the chassis sufficient to enclose all components of the receiver except that portion of the neck and socket of the cathode-ray tube which normally extends beyond the plane surfaces of the enclosure.
Maximum test voltage(2) means 130 root mean square volts if the receiver is designed to operate from nominal 110 to 120 root mean square volt power sources. If the receiver is designed to operate from a power source having some voltage other than from nominal 110 to 120 root mean square volts, maximum test voltage means 110 percent of the nominal root mean square voltage specified by the manufacturer for the power source.
Service controls(3) means all of those controls on a television receiver provided by…
Applicability.(a) The provisions of this section are applicable to cold-cathode gas discharge tubes designed to demonstrate the effects of a flow of electrons or the production of x-radiation as specified herein.
Definitions. Beam blocking device(b) means a movable or removable portion of any enclosure around a cold-cathode gas discharge tube, which may be opened or closed to permit or prevent the emergence of an exit beam.
Cold-cathode gas discharge tube means an electronic device in which electron flow is produced and sustained by ionization of contained gas atoms and ion bombardment of the cathode.
Exit beam means that portion of the radiation which passes through the aperture resulting from the opening of the beam blocking device.
Exposure−451 means the sum of the electrical charges on all of the ions of one sign produced in air when all electrons liberated by photons in a volume element of air are completely stopped in air divided by the mass of the air in the volume element. The special unit of exposure is the roentgen. One (1) roentgen equals 2.58 × 10 coulombs/kilogram.
RequirementsExposure rate limit.(c) —(1) (i) Radiation exposure rates produced by cold-cathode gas…
§ 1020.30Diagnostic x-ray systems and their major components.
Applicability.(a) (1) The provisions of this section are applicable to:
(i) The following components of diagnostic x-ray systems:
(A) Tube housing assemblies, x-ray controls, x-ray high-voltage generators, x-ray tables, cradles, film changers, vertical cassette holders mounted in a fixed location and cassette holders with front panels, and beam-limiting devices manufactured after August 1, 1974.
(B) Fluoroscopic imaging assemblies manufactured after August 1, 1974, and before April 26, 1977, or after June 10, 2006.
(C) Spot-film devices and image intensifiers manufactured after April 26, 1977.
(D) Cephalometric devices manufactured after February 25, 1978.
(E) Image receptor support devices for mammographic x-ray systems manufactured after September 5, 1978.
(F) Image receptors that are electrically powered or connected with the x-ray system manufactured on or after June 10, 2006.
(G) Fluoroscopic air kerma display devices manufactured on or after June 10, 2006.
(ii) Diagnostic x-ray systems, except computed tomography x-ray systems, incorporating one or more of such components; however, such x-ray systems shall be required to comply only with those provisions of this…
The provisions of this section apply to equipment for radiography, except equipment for fluoroscopic imaging or for recording images from the fluoroscopic image receptor, or computed tomography x-ray systems manufactured on or after November 29, 1984.
Control and indication of technique factorsVisual indication.(a) —(1) The technique factors to be used during an exposure shall be indicated before the exposure begins, except when automatic exposure controls are used, in which case the technique factors which are set prior to the exposure shall be indicated. On equipment having fixed technique factors, this requirement may be met by permanent markings. Indication of technique factors shall be visible from the operator's position except in the case of spot films made by the fluoroscopist.
Timers.(2) Means shall be provided to terminate the exposure at a preset time interval, a preset product of current and time, a preset number of pulses, or a preset radiation exposure to the image receptor.
(i) Except during serial radiography, the operator shall be able to terminate the exposure at any time during an exposure of greater than one-half second. Except during panoramic dental…
The provisions of this section apply to 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.
Primary protective barrierLimitation of useful beam.−351(a) —(1) The fluoroscopic imaging assembly shall be provided with a primary protective barrier which intercepts the entire cross section of the useful beam at any SID. 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 AKR 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 × 10 percent of the entrance AKR, at a distance of 10 cm from any accessible surface of the fluoroscopic imaging assembly beyond the plane of the image receptor. 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 §…
Applicability.(a) (1) The provisions of this section, except for paragraphs (b), (c)(1), and (c)(2) are applicable as specified herein to CT x-ray systems manufactured or remanufactured on or after September 3, 1985.
(2) The provisions of paragraphs (b), (c)(1), and (c)(2) are applicable to CT x-ray systems manufactured or remanufactured on or after November 29, 1984.
Definitions.(b) As used in this section, the following definitions apply:
Computed tomography dose index (CTDI)(1) means the integral of the dose profile along a line perpendicular to the tomographic plane divided by the product of the nominal tomographic section thickness and the number of tomograms produced in a single scan; that is:
Contrast scale(2) means the change in linear attenuation coefficient per CT number relative to water; that is:
CT conditions of operation(3) means all selectable parameters governing the operation of a CT x-ray system including nominal tomographic section thickness, filtration, and the technique factors as defined in § 1020.30(b)(36).
CT number(4) means the number used to represent the x-ray attenuation associated with each elemental area of the CT image.
(5) [Reserved]
CT…
Applicability.(a) The provisions of this section are applicable to cabinet x-ray systems manufactured or assembled on or after April 10, 1975, except that the provisions as applied to x-ray systems designed primarily for the inspection of carry-on baggage are applicable to such systems manufactured or assembled on or after April 25, 1974. The provisions of this section are not applicable to systems which are designed exclusively for microscopic examination of material, e.g., x-ray diffraction, spectroscopic, and electron microscope equipment or to systems for intentional exposure of humans to x-rays.
Definitions.(b) As used in this section the following definitions apply:
Access panel(1) means any barrier or panel which is designed to be removed or opened for maintenance or service purposes, requires tools to open, and permits access to the interior of the cabinet.
Aperture(2) means any opening in the outside surface of the cabinet, other than a port, which remains open during generation of x radiation.
Cabinet x-ray systemcabinet(3) means an x-ray system with the x-ray tube installed in an enclosure (hereinafter termed ) which, independently of existing architectural…
