What was found
LANYARD FOR ACTIVATING PASSENGER CHEMICAL OXYGEN SYSTEM FAILED DURING ACTIVATION TEST. INSPECTION OR OTHER LANYARDS ON THE ACFT RESULTED IN APPROXIMATELY 50 PERCENT FAILURE RATE. ALL LANYARDS REPLACED WITH NEW SERVICEABLE LANYARDS. OXYGEN ASSEMBLY MANUFACTURER PURITAN BENNETT WAS NOTIFIED AND IS PERFORMING FAILURE ANALYSIS ON REMOVED LANYARDS. BOEING AIRCRAFT HAS BEEN NOTIFIED AND IS INVESTIGATING THE PROBLEM.