TM 5-4220-225-14
Table 2-1. Operator Preventive Maintenance Checks and Services (Cont).
B - Before
D - During
A - After
Q - Quarterly
Interval
Item
Item to be Inspected.
Equipment Will Be
No.
B
D
A
Q
Procedure
Reported Not Ready If
HELMET ASSEMBLY (Cont)
6.
Interior.
a. Visually inspect the helmet interior for dirt, oil, and
grease, especially under the edges of the helmet
liner and mixed gas ducting.
b. Ensure all components and parts are properly
Inspection reveals any of the
installed and in good condition.
defects sighted above or
any defect that renders the
helmet inoperable.
7.
Air Supply System.
Inspect the air supply system for corrosion, dirt, oil
Inspection reveals any of the
and loose or missing screws, fittings, and component
defects sighted above or
parts.
any defect that renders the
helmet inoperable.
8.
Air Adapter and Tubing Assembly.
a. Inspect the adapter cap, filter screen, and non-
return valve and inspect for dirt, corrosion, and
cut, nicked, or deteriorated preformed packing.
Notify your supervisor if damage is found.
b. Inspect the air adapter and tubing assembly for
Inspection reveals any of the
corrosion, dirt, and damaged threads.
defects sighted above or
any defect that renders the
helmet inoperable.
9.
Supply Valve Assembly.
a. Turn the valve handle through its full range
(approximately 3-1/2 turns). Operation should be
firm but smooth. When fully shut, the valve
handle should be approximately 1/16-inch above
the helmet shell.
2-7
