I realize many eCCR 'ers don't like this. As mentioned, habitually use your eCCR as mCCR, with the "e" as back-up. I use the sound of the solenoid going-off as an alarm indicating insufficient attention to PO2. It works

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Much has to do with not complying to procedures (likewise occurs in HSE incidents in the oil industry). Emphasis on pre-dive checking and check-list utilization. I recall this as one of the "7-Sins" (see library)
Cell checking under-pressure. I wonder if an improvement could be made/designed that avoids removal/disconnection of the cells from the head. Makes everything more simple and test the unit leccies at the same time.
Installation of BOV/FFM could be considered a recomendation (don't have one yet but thinking about it).
May 2007 be fatality free!!!