ALTIMETER MISSED; LOW ALT ALERT; GAR.

Narrative

THIS WAS A CARGO FLT FROM HONG KONG -- NARITA -- ANCHORAGE. THE DEST WX ANCHORAGE WAS 600 FT OVCST; 1 1/2 MI; LIGHT SNOW. ILS 6R; ALT 2883. PRIOR TO INITIAL DSCNT THE SO RECEIVED AND PUT THE ATIS INFO ON THE LNDG BUG CARD. EXCEPT THE ALTIMETER WAS WRITTEN AS 2983. WE WERE INITIALLY CLRED TO 13000 FT. I REPEATED THE DSCNT CLRNC AND GAVE THE ALTIMETER AS 29.83. CTR DID NOT CATCH THIS IN MY READBACK. DURING DSCNT WE DID NOT LEVEL OFF AT ANY INTERMEDIATE ALTS. AT APPROX 6000 FT WE ENCOUNTERED MODERATE TO SEVERE TURB. DURING THIS TURB WE WERE TOLD WE WOULD BE LNDG RWY 6L. RWY 6R WAS BEING CLOSED FOR SNOW REMOVAL. THERE MAY HAVE BEEN ANOTHER ALTIMETER SETTING GIVEN WHEN WE WERE TRANSFERRED TO APCH CTL. BUT DUE TO THE TURB THE CHANGE OF RWYS AND HAVING TO SLOW FOR TFC; WE DO NOT RECALL ONE. WE WERE CLRED FOR RWY 6L LOC APCH AND MAINTAIN 1600 FT UNTIL ESTABLISHED AND CONTACT THE TWR. APPROX 3 MI FROM BRUCK LOM (IAF) (THIS WAS REFED FROM ANC VOR WHICH IS CLOSE TO BRUCK.) THE SO NOTICED THE RADIO ALT AT 800 FT AND THE BAROMETRIC ALT AT APPROX 1800 FT. I SAID LET'S GAR. THE CAPT STARTED THE GAR AT THE SAME TIME THE TWR RPTED THEY HAD A LOW ALT ALERT WARNING FROM US. WE WENT AROUND. THE CORRECT ALTIMETER SETTING WAS SET AND A LOC RWY 6L APCH WAS COMPLETED WITHOUT INCIDENT. AFTER LNDG WE WERE TOLD TO TAXI TO PARKING ON TWR FREQ. AS WE TAXIED WE HEARD THE TWR TELL ANOTHER ACFT THEY HAD A LOW ALT ALERT; AND TO MAINTAIN THEIR ALT. WAS THIS DONE TO AN IMPROPER ALT SETTING TOO? ATC DOES USE THE TERM LOW/LOW AFTER LOW ALTIMETER SETTINGS. AT WHAT SETTING IT IS REQUIRED? I DON'T KNOW. BUT I FEEL ANY TIME IT IS BELOW 2900 FT IT SHOULD BE USED.