The Dive Rite 2015 O2ptima scrubber canister may be loaded with either an Extendair® Cartridge (EAC) or you can self-pack the canister with approximately { 5 lbs | 2 kgs } of loose granular absorbent. Dive Rite does not have a recommendation for brand or mesh size of granular absorbent, other than it must be diving grade, but the canister was tested with Intersorb 812. Granular absorbent duration and WOB testing results are consistent with other granular scrubbers of similar absorbent capacity. For both cartridge or 812 granular absorbents and based on monitoring oxygen consumption, divers with normal CO2 production rates are getting durations† of 4 to 6 hours in { 70 °F | 21 °C } water. With the 2015 O2ptima DSV and 2.5L counter lungs, work-of-breathing at an RMV of 40 L/min for the EAC is about 1.2 Joules/Liter and granular about 1.5 Joules/Liter. Although the cartridge outperforms granular, the granular WOB is within acceptable range typical of other granular scrubbers. (The CE EN14143 rebreather standard WOB specification at RMV 40 L/min is a maximum of 1.7 Joules/Liter.) Some divers may notice better WOB with the 3.0L counter lung.

The 2015 O2ptima canister is available as an easy plug-n-play direct replacement retrofit for all previous O2ptima units. The 2015 canister is 1/2-inch longer than the previous cartridge only canister. The extra length is to allow space between the cartridge and the screen for granular plus a lip to retain the cartridge. The O2ptima fabric cover fits, but is tight on the new canister and you may wish to consider also updating to the new Kydex hard shell cover designed around the new canister.

† The duration in actual use depends upon many factors related to the individual diver, specific dive conditions and particular brands of consumables. These are observations of what experienced divers are reporting and in no way suggests exceeding manufacturer recommendations or that novices should expect these durations.