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Here is the contentious profile taken through the DCIEM tables:

	45 feet for 35 minutes - becomes 50 feet for 40 minutes => D diver
	(note that the DCIEM tables assumes a minimum 1 minute at 10 feet)
		Table 1

	2.5 hour surface interval => RF (Repetitive factor) of 1.3
		Table 4A

	60 feet for 35 minutes - becomes 60 feet for 35*1.3 = 45.5 minutes
					     (EBT - effective bottom time)

The DCIEM tables with a 1.3 RF specify a maximum of 31 minutes for
this profile to remain a no deco dive.
		Table 4B

So using the Standard Air Table, this dive using the EBT becomes

	60 feet for 50 minutes => this only specifies a 1 minute deco
				  at 10 feet, the DCIEM minimum
		Table 1

but their is a caveat in the DCIEM repetitive diving rules that requires
a minimum stop of 5 minutes at 10 feet for all dives between their No-D
limits in table 4B (repetitive dives) and the No-D limits in table 1 (which
are for first dives only).

So the dive profile with its rapid ascent is outside of the limits specified
by DCIEM.

The DCIEM tables are the most conservative I've come across (hey, maybe I should
use them!).  I agree with Bill's comments that the rapid ascent is probably
a greater contributing factor than ignoring the 'deepest dive first' rule.
It looks to me that the dive profile was marginal at best, and outside DCIEM
at worst.  The more I look at it, the more I consider repetitive diving to
be a bit of a dice game.

					Greg Ryan	gregr@cs*.su*.oz*.au*

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