TM 3-4240-212-14&P
Bausch and Lomb Standard, Semi-Rimless, Highland Bal-
are in the canister or until the oxygen-producing chemical
Grip. Personnel who must wear spectacles while using
is expended even if the apparatus is not being worn. The
the apparatus should request them from the medical
generated oxygen flows from the canister into the
officer in charge. The spectacles should meet the
breathing bag. The heat evolved during the chemical
following specifications:
reaction is dissipated as the breathing mixture circulates
in the breathing bag.
(1)
Eye size ............................ 42 to 46 mm
c. When the operator inhales, air is drawn from the
(2)
Bridge ............................. 18 to 24 mm
breathing bag through the inhalation breathing tube, the
(3)
Lens prescription plastic (CR-39), oval shape
inhalation valve in the facepiece valve assembly, and
(4)
Temple ............ size 5 1/2 in to 7 in., type CC,
then into the facepiece. A pressure relief valve in the
plain. U15b, flat without
facepiece valve assembly allows the operator to release
embossment
any excess pressure that builds up in the breathing
apparatus.
b. When wearing spectacles with the apparatus, the
M20 OBA hood must be attached to the facepiece.
1-7.
Use of Spectacles
a. Of the spectacles tested, the only ones found to
satisfactory for use with the breathing apparatus are
1-8
