[QUOTE=Capt. Phoenix;72842]Six months equals 180 (8 hour) days. Since 12 hour days count as 1.5 days you only need 120 twelve hour days to get qmed (120 + 60 = 180).[/QUOTE]
The 1.5 to 1 is for 12 hours of watches. Per 46 CFR USC 8104(g) , engineer ratings are not permitted to be dividied into two watches.