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O.C.Diver · 17th November 2008, 03:30

Quote: (Originally Posted by NorthWoodsDiver)

I am looking at buying an evo (and doing the training of course) but The biggest setback for me is scrubber size. I can see myself doing dives that are 3 or 4 hrs long (including deco of course) and the scrubber rating is only 3hrs. Now I know that number is directly related to CO2 not time and CO2 production will be different with every dive and every diver so I am just kinda looking for some numbers with approx times.

My dives primarily will be shorter as I live in minnesota where its cold 9 months out of the year and the bottom temp seldom exceeds 41 degrees F but there are times where I will be cave diving in mexico or wreck diving in florida or what ever where the water temps wont limit my dives but my scrubber will.

I also plan to do some deeper stuff (read below 200ft but no line has been drawn as to how much deeper) in both cold and warm water but obviously the cold will limit me so I dont plan to push scrubber life up here in the frigid north.

I am personally a fan of the vision setup which uses the Temp stick to monitor scrubber life span so thats partially why I settles on an AP unit over something with a larger canister. And since I wont be needing that large canister 90% of the time it would be wasted sorb anyway.

So I just want to find out kinda how long people get on average with there evo+ or equivalent volume of sorb.

While the temp stick concept is a nice idea, think of it more as a warning device as opposed to a dive planning tool. Most Rebreather are rated using the same test standards. So 2 units with 3 hour scrubbers should have similar scrubber durations as water temp and CO2 flow rates vary.

Regarding "wasted sorb":

Sorb is cheap, $10 to $15 a fill. Chose a Rebreather so that it will handle with a margin of safety, the most extreme dive you will likely do. Think of the remaining time on the sorb and remaining O2 in your tank as a huge safety factor. Visualize a silt out in the cave in Mexico. Wouldn't it be nice to know you have a 3 to 6 hour window to find your way out. Kind of like the rule of 3rds, only with a much bigger safety factor. Every time we go cave diving we start with fresh sorb and know we could double or more our run time as far as O2 and scrubber goes in an emergency.

Ted

17th November 2008, 03:30	#3 (permalink)
O.C.Diver Helium Addict Revo with Hammerhead Halcyon, MK15, Home Built Join Date: Mar 2006 Location: Salisbury MD USA Summers; Wandering Florida Winters Posts: 359	Re: Max time on Sorb? Quote: (Originally Posted by NorthWoodsDiver) I am looking at buying an evo (and doing the training of course) but The biggest setback for me is scrubber size. I can see myself doing dives that are 3 or 4 hrs long (including deco of course) and the scrubber rating is only 3hrs. Now I know that number is directly related to CO2 not time and CO2 production will be different with every dive and every diver so I am just kinda looking for some numbers with approx times. My dives primarily will be shorter as I live in minnesota where its cold 9 months out of the year and the bottom temp seldom exceeds 41 degrees F but there are times where I will be cave diving in mexico or wreck diving in florida or what ever where the water temps wont limit my dives but my scrubber will. I also plan to do some deeper stuff (read below 200ft but no line has been drawn as to how much deeper) in both cold and warm water but obviously the cold will limit me so I dont plan to push scrubber life up here in the frigid north. I am personally a fan of the vision setup which uses the Temp stick to monitor scrubber life span so thats partially why I settles on an AP unit over something with a larger canister. And since I wont be needing that large canister 90% of the time it would be wasted sorb anyway. So I just want to find out kinda how long people get on average with there evo+ or equivalent volume of sorb. While the temp stick concept is a nice idea, think of it more as a warning device as opposed to a dive planning tool. Most Rebreather are rated using the same test standards. So 2 units with 3 hour scrubbers should have similar scrubber durations as water temp and CO2 flow rates vary. Regarding "wasted sorb": Sorb is cheap, $10 to $15 a fill. Chose a Rebreather so that it will handle with a margin of safety, the most extreme dive you will likely do. Think of the remaining time on the sorb and remaining O2 in your tank as a huge safety factor. Visualize a silt out in the cave in Mexico. Wouldn't it be nice to know you have a 3 to 6 hour window to find your way out. Kind of like the rule of 3rds, only with a much bigger safety factor. Every time we go cave diving we start with fresh sorb and know we could double or more our run time as far as O2 and scrubber goes in an emergency. Ted
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