D.C. Municipal Regulations (Last Updated: September 13, 2017) |
Title 22. HEALTH |
SubTilte 22-B. PUBLIC HEALTH AND MEDICINE |
Section 22-B10852. COLD-CATHODE GAS DISCHARGE TUBES
-
10852.1The 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.
10852.2Radiation exposure rates produced by cold-cathode gas discharge tubes shall not exceed ten milliroentgens per hour (10 mR/hr.) at a distance of thirty centimeters (30 cm.) from any point on the external surface of the tube, as measured in accordance with this section.
10852.3The divergence of the exit beam from tubes designed primarily to demonstrate the effects of x-radiation, with the beam blocking device in the open position, shall not exceed Pi steradians.
10852.4Compliance with the exposure rate limit defined in § 10852.2 shall be determined by measurements averaged over an area of one hundred square centimeters (100 cm2) with no linear dimension greater than twenty centimeters (20 cm).
10852.5Measurements of exposure rates from tubes in enclosures from which the tubes cannot be removed without destroying the function of the tube may be made at a distance of thirty centimeters (30 cm) from any point on the external surface of the enclosure, provided:
(a) In the case of enclosures containing tubes designed primarily to demonstrate the production of x-radiation, measurements shall be made with any beam blocking device in the beam blocking position; or
(b) In the case of enclosures containing tubes designed primarily to demonstrate the effects of a flow of electrons, measurements shall be made with all movable or removable parts of such enclosure in the position which would maximize external exposure levels.
10852.6Measurements shall be made under the conditions of use specified in instructions provided by the manufacturer.
10852.7Measurements shall be made with the tube operated under forward and reverse polarity.
10852.8Manufacturers shall provide, or cause to be provided, with each tube to which this section is applicable, appropriate safety instructions, together with instructions for the use of such tube, including the specification of a power source for use with the tube.
10852.9Each enclosure or tube shall have inscribed on or permanently affixed to it, tags or labels, which identify the intended polarity of the terminals and:
(a)In the case of tubes designed primarily to demonstrate the heat effect, fluorescence effect, or magnetic effect, a warning that application of power in excess of that specified may result in the production of x-rays in excess of allowable limits; and
(c) In the case of tubes designed primarily to demonstrate the production of x-radiation, a warning that this device produces x-rays when energized.
10852.10The tag or label required by this section shall be located on the tube or enclosure so as to be readily visible and legible when the product is fully assembled for use.