Posted by MHK on December 04, 2000 at 15:08:59:
In Reply to: on-gassing while ascending posted by JRM on December 04, 2000 at 14:53:47:
In terms of the *clock beginning to tick etc.", by in large you are correct in that there is a built in fudge within the tables.
Tables are calculated under the modified Bulman subset B algorith, which calculates in PLANNED time. Therefore, by definition the planned dive is X feet for X minutes and thus you can use the tables..
Whereas, the Buhlman modified subset C calculates in REAL time and is used in just about every underwater computer. It is this difference between the PLANNED and the REAL time that provides for added BT's when using a computer. The computer constantly updates your actual depth and time and provides REAL time calculations respecting the M-values which of course could not be accomplished under a PLANNED dive...
Later