Dare I suggest the person you spoke to is a complete plonker.
There are more productive ways to kill brain cells than faking a CO2 hit.
This has been discussed endlessly, lots of threads on here about it, try a search... not that we can't discuss it again of course....
Short story- Scrubber is Cheap, Life is Valuable.
Do the hours, bin the kitty litter and repeat.
I've always figured pushing slime time leaves you with very little reserve if something else fails, even 3hours into a fill there is probably some reserve for climbing out of the incident pit, 4 or 5hours in that might not be an option. (IMVHO of course)
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Know your PPO2, Pre-breath, Use checklists, Validate cells at 6mtrs, Use pure O2 at or near surface, Use a BOV, Don't dive Solo, Change Slime and Cells as recommended by Manufacturer and RTFM!
Beware Fridge Suck!
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