AN MD80 CAPT RPTS CREW OXYGEN TESTS IN OPERATING MANUAL DO NOT CHK FOR PNEUMATIC INTEGRITY OF THE SYS.

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DEALING WITH CREW OXYGEN PROBS ON THE MD80. I AGREE THAT STRICT ADHERENCE TO THE PROCS ON PAGE 170 SYS DC9 OPERATING MANUAL; WILL ENSURE FLOW TO THE CREW OXYGEN MASK. THESE PROCS; HOWEVER; DO NOT CHK THE PNEUMATIC INTEGRITY OF THE SYS NOR DO THEY INCLUDE STEPS TO ENSURE THAT POSITIVE FLOW IS DELIVERED TO THE OXYGEN MASK VENT; WHICH I HAVE FOUND DEFECTIVE ON ONE OCCASION. A RECOMMENDED MANNER IN WHICH TO CHK FOR TOTAL INTEGRITY OF THE SYS IS TO DON THE MASK; INHALE AND EXHALE TO CONFIRM FLOW; AND THEN TO PLACE THE EMER (NORMAL) TEST MASK CTL TO THE TEST MASK POS. NEXT; TAKE A DEEP BREATH AND HOLD WHILE PRESSING ON THE OXYGEN MASK VENT TO ENSURE FLOW. RELEASE THE VENT TO ENSURE FLOW STOPS. WHILE STILL HOLDING BREATH; ENSURE THAT THE FLOW INDICATOR IS BLANK; IE; NO FLOW. IF FLOW PERSISTS; INVESTIGATE. I HAVE FOUND 2 OXYGEN SYS THAT HAD SIGNIFICANT LEAKS UNDER POSITIVE PRESSURE THAT WOULD NOT HAVE BEEN DISCOVERED USING CURRENT PROCS. ACFT #1 AUG/XA/02 WITH A LEAK AT THE REGULATOR. ACFT #2 SEP/XA/02 WITH A LEAK IN THE HOSE BTWN THE REGULATOR AND THE SIDE WALL. PLEASE CONSIDER THESE RECOMMENDED CHANGES AND ALSO CONSIDER CHKING OUR MD80 FLEET BY PLUGGING THE HOLE AT THE SIDEWALL AND APPLYING POSITIVE PRESSURE UPSTREAM OF THE PLUG. IF FLOW STOPS; THEN GOOD. IF FLOW DOES NOT STOP; THEN BAD.