PREFLIGHT/POSTFLIGHT INSPECTION

Figure 4-26.—Adjustment of bayonet receivers. Adjustment of Bayonet Receivers To adjust the bayonet receivers, loosen the two adjusting screws (fig. 4-26) and rotate the receivers until the mask fits properly. Retighten the adjusting screws. NOTE: Ensure that the top buckles are tacked down prior to any adjustment. Adjustment of the bayonet receivers is performed with the helmet assembly and oxygen mask assembly donned by the aircrew member. When properly fitted, the MBU-12/P oxygen mask can retain a pressure in excess of ambient pressure up to the maximum pressure supplied by the regulator. Maintenance Proper care and use of oxygen masks is essential to ensure optimum performance during routine flight operations and emergencies. The aircrew member’s responsibility for maintenance of the oxygen mask is limited to cleaning. Repairs or other maintenance actions required are performed at the organizational level or above. PREFLIGHT/POSTFLIGHT INSPECTION The preflight/postflight inspection is a visual inspection performed by the aircrew member to 4-31 whom the oxygen mask is issued before each flight. The preflight/postflight inspection consists of-the following-procedures: NOTE: Defects or questionable areas noted during this inspection must be referred to the proper maintenance activity for required corrective action. 1. Check the communication system and microphone for proper installation. 2. Check the mask for damage and proper operation by using the tester and/or aircraft oxygen and communications system. Calendar Inspection The calendar inspection is conducted every 30 days at the organizational level and consists of a visual inspection, a functional check, and a thorough cleaning of the oxygen mask assembly. Refer to NAVAIR 13-1-6.7 for visual inspection and functional check procedures. NOTE: If a discrepancy is noted, refer to table 4-4 for guidance. Cleaning Mask To clean and sanitize the oxygen mask facepiece and housing assembly, proceed as follows: Preferred solution. Make a 1 percent by weight solution of cleaning compound (Detergent, Gen- eral Purpose, MIL-D-1 6791, Type I) by adding 1/4 to 1/2 ounce (liquid) of the compound to 1 gallon of water. CAUTION WHEN THE FOLLOWING ALTER- NATE CLEANING SOLUTION MUST BE USED, ONLY THE LATHER FROM T H E S O L U T I O N I S U S E D F O R CLEANING. THIS PREVENTS UN- DISSOLVED SOAP SOLUTION FROM GETTING INTO THE VALVE. Alternate solution. Make a suitable soap solution by adding approximately 4 tablespoons of soap powder (P-S-600) to 1 gallon of water. Hardness of water may require more soap, but the solution must be sufficiently strong to readily form lather when agitated. Make sure that all soap particles are dissolved.