liberty rebreather scrubber time.

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That seems just a bit overly dramatic. Yes, it is bad to unpack and repack sorb. Never ever do that! But's it's not instant death either. A CO2 hit can be dangerous but it's not like hypoxia where you just pass out. It could trigger a cascade leading to panic, but it can also be recovered safely.

I've had a CO2 hit before. My experience was that I did one dive on fresh packed sorb, then drove several hours to another location and did another dive the next day. In the first 10 minutes of that dive I started to get very irritable and frustrated over nothing. Then I started breathing faster. I quickly realized my loop was bad and bailed out. On OC bailout stayed put for a few minutes and got my composure back. I did a safe ascent with my buddy and all was well.

I suspect that some channeling occurred in my scrubber during the drive which allowed for a breakthrough. This was on a Sport Kiss about 10 years ago. That unit's scrubber does not have a spring loaded cap holding the scrubber in place and it's a single chamber canister. I have since moved to a Kiss Spirit with two canisters with a simple cylinder shape and tight spring loaded heads. A much better design.
Id think that at a low workload you might not even notice. Have to work a bit? Now that reduced scrubber efficiency could cook your goose.
 
Id think that at a low workload you might not even notice. Have to work a bit? Now that reduced scrubber efficiency could cook your goose.

I had a very low workload. I had just dropped on a wall with no current. In just a few minutes I was feeling anxiety and starting to hyperventilate. I understand these are pretty common reactions.
 
I had a very low workload. I had just dropped on a wall with no current. In just a few minutes I was feeling anxiety and starting to hyperventilate. I understand these are pretty common reactions.
Im curious as to how much of your scrubber time you had used.

But I guess I should have stated in my above post that a mixed (used and unused granules mixed together) might go undetected depending on workload.
 
Im curious as to how much of your scrubber time you had used.

But I guess I should have stated in my above post that a mixed (used and unused granules mixed together) might go undetected depending on workload.

I had loaded fresh scrubber the night before and then done about 1 hour of diving. Then I loaded everything up and drove about 4 hours. The next day I had a break through on the first dive within minutes. For sure it was channeling from the agitation of the drive. The scrubber should have been good for 3-4 hours in 50F water temps.
 
I had loaded fresh scrubber the night before and then done about 1 hour of diving. Then I loaded everything up and drove about 4 hours. The next day I had a break through on the first dive within minutes. For sure it was channeling from the agitation of the drive. The scrubber should have been good for 3-4 hours in 50F water temps.
Descending on the scrubber design if it’s laid down on its back that’s a possibility.
 
I had loaded fresh scrubber the night before and then done about 1 hour of diving. Then I loaded everything up and drove about 4 hours. The next day I had a break through on the first dive within minutes. For sure it was channeling from the agitation of the drive. The scrubber should have been good for 3-4 hours in 50F water temps.

How much bail out did you go through. and from what depth? and how long did it take to fully recover at surface?
 
When you guys say "channeling" I pictured a gap or area of no sorb that gas would easily pass thru verses the sorb. Is channeling also a path of used up sorb?

If gas is passing from outer to inner area, is it somewhat of a used up area of sorb on the outer surface that gradually moves inward as the sorb is used?
 
When you guys say "channeling" I pictured a gap or area of no sorb that gas would easily pass thru verses the sorb. Is channeling also a path of used up sorb?

If gas is passing from outer to inner area, is it somewhat of a used up area of sorb on the outer surface that gradually moves inward as the sorb is used?

What @davehicks described is a gap of no sorb that happens due to either bad packing of the scrubber or vibration that causes weird settling.

What we were talking about with repacking a scrubber is a path of used up sorb. On radial scrubbers that is out to in, on axial it is top to bottom. Axial is a lot less likely to channel
 
How much bail out did you go through. and from what depth? and how long did it take to fully recover at surface?

It was unremarkable. I had dropped to maybe 60' when I had the issue. I surfaced on 21% OC from my 40cf bailout. I don't typically dive below 100' or plan on deco. I stayed there for a few minutes recovered off the loop and went to the surface. I don't recall any issues or recovery needed at the surface. I changed my scrubber and did a couple more dives that day.
 
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