TM 10-8415-208-12 Table 2-1.  Operator Preventive Maintenance Checks and Services for the STEPO-I (Cont) B - Before Operation D - During Operation INTERVAL Item Item To Be Procedures Equipment Is No. Inspected Check For And Have Repaired Not Ready/ B D Or Adjusted As Necessary Available If: 20 • Face Piece Inspect for cuts, holes or any Cuts, holes or other damage and ensure inlet damage is found or and outlet valves are installed. inlet and outlet valves are missing. 21 • Ensure lens is clean. Dirty lens. 22 • Breathing Inspect breathing tube for Damage is found or Tube damage and ensure the cover cover not tied on. is tied at both ends. 23 • Face Piece Ensure warning light lamp is Lamp not installed. Light installed. CAUTION Equipment corrosion hazard.  Remove the battery from the EBA battery box when the unit is not in use.  Failure to remove the battery may cause equipment damage from corrosion and require replacement of the EBA. 24 • Battery Ensure "D" size battery is installed. Battery is missing. 25 • Cylinder Check the pressure gauge to Cylinder is charged ensure the cylinder is charged below the full mark. to approximately 2500 psig. 26 • Cushion Ensure cushion cover is Cushion cover not Cover installed. installed. NOTE PMCS steps 27 through 43 are checked only when using the rebreather system. Rebreather System (Rebreather System Mode) 27 • Rebreather Visually ensure unit is clean. Unit is dirty. 28 • Bypass Button Depress the bypass button to The bypass button ensure it operates properly. fails to operate. 29 • Face Piece Lens Ensure lens is clean. Lens is dirty. 2-10