What membrane has been used to prevent water from passing, but would allow regular air to pass?
FAQ
The common membranes used for gas/air filtration are hydrophobic Polypropylene (PP) and PTFE. They both inhibit the flow of water while allowing air to pass.
The table below is to show the water intrusion pressure of PTFE membrane which is based on the principle of the smaller the pore size is, the greater intrusion will be.
Water intrusion of PTFE | |
Pore size (um) | Water intrusion pressure (psi) |
0.2 | 40 |
0.45 | 20 |
1.0 | 7 |
3.0 | 2 |
5.0 | 1 |
