BD700 CREW DID NOT KNOW THE DIFFERENCE BTWN QNH; QNE; ALTIMETER SETTING IN MM AND ALTIMETER SETTING IN HPA.

Narrative

WHILE DSNDING PAST THE TRANSITION LEVEL TO AN ASSIGNED ALT; MOSCOW APCH ADVISED US OF THE ALTIMETER SETTING IN MILLIMETERS. ON OUR PRE-DSCNT BRIEFING WE NOTED THAT QNH WAS AVAILABLE ON REQUEST; AND OUR POLICY IS TO FLY QNH WHENEVER POSSIBLE; TO ELIMINATE ALT ERRORS. I ASKED THE CO-CAPT TO REQUEST THE ALT ASSIGNMENTS IN QNH. AS WE DSNDED AND CIRCLED OVER THE ARPT IN DAYTIME VISUAL CONDITIONS; THE CTLR ADVISED US OF THE ALTIMETER SETTING AGAIN IN MILLIMETERS. I IMMEDIATELY ASKED THE CO-CAPT TO VERIFY THAT THE ALTIMETER ASSIGNMENT WAS ISSUED IN QNH MEASUREMENTS. THE CTLR SEEMED TO NOT UNDERSTAND THE REQUEST. I THEN NOTICED THAT THE RADIO ALTIMETER SHOWED THAT WE WERE AT THE APPROPRIATE ALT; IF THE ISSUED ALTIMETER SETTING HAD BEEN IN QNH. WE ASKED THE CTLR TO VERIFY THE QNH SETTING AND HE RECONFIRMED THAT THE ALTIMETER SETTING WAS IN MILLIMETERS. I AM CONVINCED THAT HE DID NOT UNDERSTAND OUR REQUEST FOR QNH INSTEAD OF QFE. WITH THE USE OF THE RADIO ALTIMETER; WE CONCLUDED THAT WE WERE AT 600 METERS QNH AND THE CTLR WANTED US AT 600 METERS; EVEN THOUGH HE DID NOT USE THE TERMS QFE OR QNH IN ANY OF HIS XMISSIONS. WE SURMISED THAT WE WERE 200 METERS LOWER THAN THE CTLR WANTED US TO BE. WE CONCLUDED THAT THE LANGUAGE BARRIER AND PERHAPS SOME MISUNDERSTANDING OF THE 'QNH ON REQUEST' ISSUE BY THE CTLR; CONTRIBUTED TO THIS EVENT. WE ARE REEVALUATING OUR POLICY OF ALWAYS USING QNH WHENEVER POSSIBLE. PERHAPS IF WE CONFORM TO THE LOCALLY USED METHODS OF ALTIMETRY MEASUREMENTS; THE LANGUAGE BARRIER EFFECT WILL BE MINIMIZED.