CFR > Title 42 - Public Health > CHAPTER I—PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES > SUBCHAPTER G—OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES (parts 80 to 87) > PART 84—APPROVAL OF RESPIRATORY PROTECTIVE DEVICES > SUBPART J—Supplied-Air Respirators (§84.130 to §84.163) > 84.152—Breathing tube test; minimum requirements.

84.152—Breathing tube test; minimum requirements.

(a) (1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from the facepiece to a connecting hose coupling attached to the belt or harness.
(2) The breathing tubes employed shall permit free head movement, insure against closing off by kinking or by chin or arm pressure, and they shall not create a pull that will loosen the facepiece or disturb the wearer.
(b) Breathing tubes employed on Type C supplied-air respirators of the continuous flow class shall meet the minimum requirements set forth in paragraph (a) of this section, however, an extension of the connecting hose may be employed in lieu of the breathing tubes required.
(c) (1) A flexible, nonkinking type breathing tube shall:
(i) Be employed on Type C supplied-air respirators of the demand and pressure-demand class; and
(ii) Extend from the facepiece to the demand or pressure-demand valve, except where the valve is attached directly to the facepiece.
(2) The breathing tube shall permit free head movement, insure against closing off by kinking or by chin or arm pressure, and shall not create a pull that will loosen the facepiece or disturb the wearer.