Quote: (Originally Posted by
Genesis)
The possibility of flattening a battery to the point where you have a problem underwater without realizing it is higher than that of going in with the unit off and not looking at the handset prior to the loop going hypoxic and killing you.
BOTH require inattention.
But so does going in with the gas off on OC, and yet according to the DAN statistics this gets, on average, one person a year.
But there is no requirement in CE this-or-that mandating automatic gas valves! They could - but they don't.
The CE issue first: if the unit has any electronics in it, or electrical, then EN14143:2003 requires compliance with EN61508, and that requires SIL4, which means that collectively all the critical failure modes together must have with an incidence of less than 1 per billion hours. As there are only about 5000 rebreathers in active use by sports divers, then if there is one death per year from this cause alone, then the system does meet any Safety Integrity Level required by Table 3 of EN61508-Part 2, and 10,000 times worse than the SIL-4 level required.
On the battery issue, you are absolutely correct. Dead battery should not mean dead diver.
Alex