mislav:
Agreed, Nereas - I also promote diving on Nitrox on every occasion possible. In fact - I've done 5 Nitrox dives this last weekend. Outside of that club of course, they don't dive Nitrox...
With an increasing number of dive centers offering free EAN fills I see Nitrox diving as the future of rec diving. Voodoo gas is going mainstream.
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Cool!
Just for more info, for you, on the technical part of their policy, it is perfectly normal to plan and carry out 2 deco dives in one day, as well. Repetitive deco diving is no more unusual than repetitive NDL diving. This is precisely why I have 2 sets of doubles, of each size that I own, small and large. (4 of them. They take up a lot of room.)
The only issue is the depth and time spent on the first dive, regarding what the required surface interval must be. Generally speaking, a 2 hour surface interval is considered to be the minimum between any 2 deco dives.
However you must use a software program like V-Planner to determine when a longer surface interval is needed. The required surface interval can be anywhere from 2 to 6 hours, according to the V-Planner model.
In addition, some agencies such as NAUI-Tech have additional safety rules forbidding a repetitive deco dive within 12 hours, if the first dive has been 250 fsw or deeper (75 meters). [I don't know exactly what their rules are now, but once upon a time, that was one of their rules.]
That is just food for thought, for you, since you seem like a very well informed person, who likes to obtain more knowledge.