As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED O2 LEAK, INSUFFICIENT QTY FOR CONTINUING TO ANC, DIVERTED TO YYC. CAPT O2 MASK HAD JUST BEEN REPLACED IN JFK PRIOR TO DEPARTURE.(<P>FOUND LOOSE FITTING ON 1ST OBSERVER O2 MASK BOX AND RETORQUED IAW AMM 35-11-18. NO FURTHER DEFECTS NOTED</P>)