(a) The apparatus shall satisfy the respiratory requirements of the wearer for the classified service time.
(b) Fogging of the eyepiece shall not obscure the wearer's vision, and the wearer shall not experience undue discomfort because of fit or other characteristics of the apparatus.
(c) When the ambient temperature during testing is 24 6 [deg]C. (75 10 [deg]F.), the maximum temperature of inspired air recorded during man tests shall not exceed the following, after correction for deviation from 24 [deg]C. (75 [deg]F.): ------------------------------------------------------------------------
Where percent Maximum permissible
relative temperature of inspired
Where service life of humidity of air shall not exceed--
apparatus is-- inspired air -------------------------
is-- [deg]F. [deg]C.------------------------------------------------------------------------\1/4\ hour or less............ 0-100 135 57\1/4\ hour to \3/4\ hour...... 0-50 125 52
50-100 \1\ 110 \1\ 431 to 2 hours.................. 0-50 115 46
50-100 \1\105 \1\413 hours....................... 0-50 110 43
50-100 \1\100 \1\ 384 hours....................... 0-50 105 41
50-100 \1\ 95 \1\ 35------------------------------------------------------------------------\1\ Where percent relative humidity is 50-100 and apparatus is designed
for escape only, these maximum permissible temperatures will be
increased by 5 [deg]C (10 [deg]F).