Here is my thinking:
1. First of all, for these *recreational* dives, I would be completely comfortable using a P02 of 1.5 ata. So, I would be completely comfortable using NOAA Nitrox II at 100 fsw. (Moreover, this is completely consistent with what was taught in the IANTD Nitrox course I took in 1993 or so.)
2. For *planning* these 100 fsw recreational dives, I would compute using a max depth of 110 fsw (rather than 100 fsw), for which EAN36 has a corresponding PO2 of 1.6 ata, which has a NOAA CNS oxygen limit of 45 min.
Keep in mind, I am assuming you have only someone's (US Navy in my case) standard air tables, an oxygen analyzer, and a pencil and slate (and, maybe, a calculator).
Freewillow, Centrals, et al, does this additional detail help? If I can find some extra free time, I'll actually run through the hand calculations. It will be a fun exercise, and, besides, I'll get a chance to use the new iPhone HP 15C calculator app (reverse Polish notation) I recently purchased from Hewlett Packard!
Safe Diving,
rx7diver