As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SNN - FL49 - EN ROUTE CDG TO PHL, CREW NOTED ON EICAS THE CREW OXYGEN PRESSURE HAD FALLEN TO 50. FLIGHT DIVERTED TO SNN AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE IN SNN CONFIRMED THAT THE FIRST OFFICERS MASK/REGULATOR/BOX ASSEMBLY WAS LEAKING. THE UNIT WAS SWAPPED WITH THE 2ND OBSERVER'S UNIT, THE 2ND POSITION OXYGEN LINE CAPPED AND THE OXYGEN SYSTEM SERVICED. THE FLIGHT CONTINUED TO PHL. MAINTENANCE AT PHL REPLACED UNIT. (M)