TM 10-8415-208-12 Table 3-2.  Unit Preventive Maintenance Checks and Services for the STEPO-I(Cont) A - After Operation Q - Quarterly INTERVAL Item Item To Be Procedures Equipment Is No. Inspected Check For And Have Repaired Not Ready/ A Q Or Adjusted As Necessary Available If: Rebreather System (Rebreather System Mode) 42 Rebreather Clean, disinfect and sanitize the Unit not clean. system. (See paragraph 3-10.5) 43 Visually ensure unit is clean. Unit is dirty. 44 Bypass Button Depress the bypass button to The bypass button ensure it operates properly. fails to operate. 45 Face Piece Ensure lens is clean. Lens is dirty. 46 Inspect for cuts, holes or any Cuts holes or other damage. damage is found. 47 Air Hoses Inspect hoses for cuts, holes or Cuts, holes or any other damage. damage is found. 48 Disconnect air hoses from face piece. Air hoses connected. NOTE The CO₂ absorbent must be replaced if the air hose plugs are missing. 49 Air Hose Plugs Ensure red plugs are installed in Plugs missing. the ends of the exhalation hose and coolant canister hose. NOTE The CO₂ absorbent will be replaced after each use or every 12 months for a unit in storage. 50 CO₂ Absorbent Ensure maintenance tag Maintenance tag is indicates CO₂ absorbent is fresh. missing or outdated. 51 Change the CO₂ absorbent. Absorbent not (See paragraph 3-10.2) changed or maintenance tag missing. 52 ·    Absorbent Ensure preformed packing are Preformed packing Canister Well clean and have a thin film of are dirty, cut or have Preformed silicone lubricant on them. no lubricant. Packing 53 Coolant Ensure canister is placed in Canister not frozen. Canister freezer. Change 2  3-140