I had a sensor (R22D) "go out" on me recently. If removed from the bag, the cell should be considered operational. The bag is a lot more important than it may appear. If removed from a bag and resealed it can increase the failure rate: the gas in the bag should not be dry nitrogen.

Teledyne sensors failed many of the tests in the report with a lot of quality control issues. We had things like sensors that should be 8s response time being 50s, leaking issues, early failures, etc. IMHO, there is a considerable amount of work to be done by Teledyne to produce sensors suitable for rebreathers. The highest levels at Teledyne do seem committed to put in that work, and we will report the results when they succeed. We cut the Teledyne results from the report, otherwise it reads as too much of an inditement on their products. Having at least two sources is good for everyone, so Teledyne should be allowed to do this without focusing on the past.

Until they have a suitable product, the low risk approach is to use the AI equivalent (in this case, PSR-11-39-MD). The AI cells were the only ones we found suitable for rebreather applications. Alas.

Alex