so given the analysis of ccr related deaths what % are machine breakdown versus human error
If only it were that simple.
So many factors go into it. Is there a problem with the unit? Did the diver know about it and still dive? Did the problem arise underwater? What caused the problem - was it diver error in the build or was it a mechanical failure that was unforeseeable? Did the electronics function properly to warn the diver of the problem? Did the warnings go unseen/unheeded? What was the outcome of the failure - did it cause hypercapnia (which causes confusion and a definite slowing of reaction time) or did it cause hyperoxia (which can cause unrecoverable convulsions leading to drowning) or did it cause hypoxia (which can cause dizziness and the inability to act)? Did someone choose the wrong gas to inject? Was the scrubber packed improperly? Were the oxygen sensors current limited? Were they properly calibrated? Were they too old? Was the oxygen turned off? Was the diluent a hypoxic mix and breathed too shallow?
I've experienced hypoxia and had to be saved. I never want to experience that again! Had I not been brought back to life, would my death have been considered an equipment failure? Possibly, as it was not giving me oxygen. Would that have been 100% accurate? No, because it was a known issue and I chose to splash. So does that make it a human error? Definitely. But if I had not been brought back, how would we have known?
Blaming the technology, the manufacturer, the individual unit, or blaming the diver is seldom the whole story. It's kind of like asking a couple going through a divorce what the cause of the divorce is. Rarely is it just one issue. Terrible analogy maybe, especially given that I am in the middle of that myself, but painfully accurate. That is why there is no way to come up with that magical number assigning blame. The ones who know all the answers can not contribute to the discussion.