Posted by northcoast diver on January 24, 2005 at 09:51:40:
In Reply to: Thanks... posted by Eric S on January 23, 2005 at 20:59:46:
Twin 72s are perfect for dives in the 150 to 180 range. Here is a deco plan that I recommend for you. At first, your intructor will have you use only one deco bottle with EAN50. But ultimately, you will want to consider TWO OF EVERYTHING, even for shallow deco diving.
V-Planner 3.43 by R. Hemingway, VPM code by Erik C. Baker.
Decompression model: VPM-B
DIVE PLAN #1
Surface interval = 5 day 0 hr 0 min.
Elevation = 0ft
Conservatism = + 3
Dec to 180ft (3) on Trimix 20.0/40.0, 50ft/min descent.
Level 180ft 16:24 (20) on Trimix 20.0/40.0, 1.29 ppO2, 75ft ead, 95ft end
Asc to 100ft (22) on Trimix 20.0/40.0, -30ft/min ascent.
Stop at 100ft 0:20 (23) on Trimix 20.0/40.0, 0.80 ppO2, 34ft ead, 47ft end
Stop at 90ft 1:00 (24) on Trimix 20.0/40.0, 0.74 ppO2, 29ft ead, 41ft end
Stop at 80ft 1:00 (25) on Trimix 20.0/40.0, 0.68 ppO2, 24ft ead, 35ft end
Stop at 70ft 1:00 (26) on Nitrox 50.0, 1.56 ppO2, 32ft ead
Stop at 60ft 1:00 (27) on Nitrox 50.0, 1.41 ppO2, 26ft ead
Stop at 50ft 2:00 (29) on Nitrox 50.0, 1.26 ppO2, 20ft ead
Stop at 40ft 3:00 (32) on Nitrox 50.0, 1.10 ppO2, 13ft ead
Stop at 30ft 4:00 (36) on Nitrox 50.0, 0.95 ppO2, 7ft ead
Stop at 20ft 2:00 (38) on Oxygen, 1.60 ppO2, 0ft ead
Stop at 15ft 11:00 (49) on Oxygen, 1.45 ppO2, 0ft ead
Asc to sfc. (49) on Oxygen, -30ft/min ascent.
Off gassing starts at 129ft
OTU's this dive: 67
CNS Total: 28.5%
104.9 cu ft Trimix 20.0/40.0
12.5 cu ft Nitrox 50.0
9.6 cu ft Oxygen
127.1 cu ft TOTAL
DIVE PLAN #2
Surface interval = 0 day 3 hr 0 min.
Elevation = 0ft
Conservatism = + 3
Dec to 150ft (3) on Trimix 20.0/40.0, 50ft/min descent.
Level 150ft 17:00 (20) on Trimix 20.0/40.0, 1.11 ppO2, 60ft ead, 77ft end
Asc to 70ft (22) on Trimix 20.0/40.0, -30ft/min ascent.
Stop at 70ft 0:20 (23) on Nitrox 50.0, 1.56 ppO2, 32ft ead
Stop at 60ft 1:00 (24) on Nitrox 50.0, 1.41 ppO2, 26ft ead
Stop at 50ft 1:00 (25) on Nitrox 50.0, 1.26 ppO2, 20ft ead
Stop at 40ft 2:00 (27) on Nitrox 50.0, 1.10 ppO2, 13ft ead
Stop at 30ft 2:00 (29) on Nitrox 50.0, 0.95 ppO2, 7ft ead
Stop at 20ft 2:00 (31) on Oxygen, 1.60 ppO2, 0ft ead
Stop at 15ft 8:00 (39) on Oxygen, 1.45 ppO2, 0ft ead
Asc to sfc. (39) on Oxygen, -30ft/min ascent.
Off gassing starts at 108.1ft
OTU's this dive: 50
CNS Total: 28.7%
86.6 cu ft Trimix 20.0/40.0
8.0 cu ft Nitrox 50.0
7.5 cu ft Oxygen
102 cu ft TOTAL
DIVE PLAN COMPLETE