TM 55-1930-209-14&P-19 Table 7-2.  Preventive Maintenance Checks and Services for Compressed Air System (Continued) B - Before D - Daily Q -  Quarterly D - During W - Weekly S -  Semiannually A - After M - Monthly A -  Annually INTERVAL ITEM PROCEDURES EQUIPMENT ITEM TO BE CHECK FOR AND HAVE IS NOT READY/ NO. INSPECTED REPAIRED OR ADJUSTED AVAILABLE IF B   D   A   D  W  M   Q   S   A AS NECESSARY e. Check     receiver     safety valve on all com- pressors (Barges 1, 2, and 3). 1) Pull up on safety link on safety valveAir does not in top of receiver.  Air should escape escape from from valve. valve. WARNING System MUST NOT be operated without an  operating  receiver  safety  valve.    In the event that the compressor continues   to   run   beyond   factory   set pressure,   this   valve   reduces   receiver pressure to a sale level. 2) If air does not escape, replace receiver safety valve.  This valve can not be adjusted or repaired.  Replace as follows: (a) Shut down air compressor sys- tem. (b) Redtag power panel 1 circuit breaker 3P5 indicating, "WARNING - DO NOT ACTIVATE. REPAIRS BEING MADE." (c) Unscrew safety valve. (d) Screw in new safety valve (Barge 1 - P/N 9710-5332-00) (Barges 2 and 3 - P/N 91A033175-001) wrench tight. (e) Start air compressor system. (f) When receiver pressure gauge reads at least 100 psi, check receiver safety valve by pulling safety link.  Air should escape from receiver thru valve.  If not, repeat above procedures and install another new safety valve.  This valve is NOT adjustable or repairable. (g) Remove red tag from power panel 1 circuit breaker 3P5. 7-19