Popup valve for Covid-19 ventialtor

[Butt_blaster]

You may not like my advice here, because I'm sure you've sunk some serious hours into your design, but just buy an off the shelf pressure relief valve and adapt it to your tubing.

Real engineers (not saying you aren't one) have spent time getting paid a lot of money and running hundreds of hours of tests to develop good spring-loaded pressure relief valves that work dependably and cost not very much money. Try not to get bogged down with reinventing the tangential details of your project, you'll just sink days into something that only barely applies to what you originally set out to do.

[Tim1]

You may not like my advice here, because I'm sure you've sunk some serious hours into your design, but just buy an off the shelf pressure relief valve and adapt it to your tubing.

Real engineers (not saying you aren't one) have spent time getting paid a lot of money and running hundreds of hours of tests to develop good spring-loaded pressure relief valves that work dependably and cost not very much money. Try not to get bogged down with reinventing the tangential details of your project, you'll just sink days into something that only barely applies to what you originally set out to do.

I tried looking for one but I had trouble finding the right one. Most pressure relief valves on market are in the range of 10-300 PSI while I need one rated 0.85PSI (60 cmH2O). I guess the only manufacturers for such valves will be medical manufacturer that will charge a lot for each valve.
Please let me know if you can find a website selling 60 cmH2O pressure relief valve.