The PSRF filters are constructed from hydrophobic glassfibre…they do not meet the requirements for sterile air in pharma. Testing can be carried with a portable aerosol challenge device sold by Parker …Valairdata, it uses Ondina Oil and has a pass/fail value. It should work with the PSRF (pass when it’s intact!), but I’m not 100% certain. If the PSRF is pleated, then you’re probably OK, if it’s not pleated, then the face velocity might be too high because the area is much lower (it’s like a toilet roll), and this can result in a loss in efficiency.
I think for F&B it should be fine, in pharma, I’d be inclined to use PTFE membrane filters, because the testing corresponds closely with the requirements of PDA TR40 ‘Sterilizing Filtration of Gases’…that the filter must be validated to retain bacteria in a liquid challenge.