Operator Preventive Maintenance Checks and Services (Cont)

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