April 8th Duration tests

Endurance tests on the ambu bags showed failure after 160’000 cycles. Bags were fully depressed at 1Hz. This translates to failure after 3 days of RR=35 BPM at full volume (1000 mL).

Failure mode is a tear near the hard, plastic endcap of the ambu bag.

We have updated the plunger design, to a narrower & more rounded version. This still achieves the requires Vt of 800mL , while putting less stress on the edges of the ambu bags.

The test version also did not have the silicone covers.
This updated version has been sent to the test facility.