84.1132—Breathing tubes; minimum requirements.
(a)
Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:
(1)
Restriction of free head movement;
(2)
Disturbance of the fit of facepieces, mouthpieces, hoods, or helmets;
(3)
Interference with the wearer's activities; and
(4)
Shutoff of airflow due to kinking, or from chin or arm pressure.