Hi @stuartv
Over the years, I have struggled with trying to understand the ANSTI simulator testing of regulators. Some background for the testing equipment can be found at Ansti Test Systems Ltd under products/Life Support Equipment Test Facility.
The graphics results in the recent Scuba Diving article are mislabeled and make it harder to understand. The first parameter listed should be RMV rather than BPM, i.e. 37.5 RMV. The breathing rates used are actually 15, 30, and 25 breaths/min @ 2.5 liters per breath. This generates the RMVs of 37.5, 75, and 62.5 liters per minute, corresponding to 1.32, 2.65, and 2.21 cubic feet per minute.
Thank you for that bit of info! That puts things much more in perspective.
I have the computer-recorded-via-AI gas consumption data from pretty much every dive I have ever done. My highest RMV over the course of a whole dive was 1.36cu-ft/min, on a 20 minute dive with a max depth of 45'. Looking at the dive's data, I can see a stretch early in the dive with a sustained RMV over 3.0 for around 3 minutes, with a peak of 3.6 cu-ft/min. That was just me. The dive was just over 1 year ago and my notes tell me where I was and who I was with, but I don't really remember the dive specifically. It was just practice in the local quarry.
I might throw out that dive's data as an outlier. I don't think I had a 3-minute long free-flow, but maybe I'm just really forgetful.
I have numerous other dives where I have short periods of an RMV over 2.0, even though the overall dive average is only a little over 1.0.
So, a test that simulates RMV of 1.32 and 2.65 seems completely relevant to me. A reg that would give me any noticeable increase in WOB in the scenario where I am sharing with a buddy and we are, for example, working to get back to an anchor line is probably one I would prefer to avoid.
However, what @tbone1004 said about diver orientation and how that affects the results also means the Scuba Labs results are not really something I can necessarily draw any conclusions from.
Hmmm...
I am still curious about different reg designs and how one setup could become a little harder to breathe when face-up and another setup could become a lot harder to breathe when face-up. I would have thought that if the regs are the same distance apparent, then the change in WOB would be the same when you invert the orientation.
The Deep6 Signature is basically a Version 2.0 of the HOG Zenith. It is the same basic design but has some minor tweaks that make it a bit better than the Zenith. Parts kits are interchangeable on the regulators fwiw. If you are looking at HOG for that reason, the Deep6 will breathe a bit better and are of a bit higher quality due to the internal material improvements, and represent a better value since they include the first service for free and also include the first set of parts kits for free
Are you saying the parts kits are interchangeable between a HOG D3/Zenith and a Deep6 Signature 1st/2nd?