BTW/FWIW the magenta color of the filters indicate that these are P100. (‘100’ means minimum 99.7% of 2.5 micron particulate matter filtered out, and ‘P’ means the filter is not degraded by airborne oil mist). NIOSH specifies this color coding (for OSHA workplace inspection, I’d guess). The GVS Elipse might be more appropriate for medical personnel, as that respirator is low-profile (no canisters) and fits under many welding masks, so probably would work well with a transparent face shield. Canister-style respirators do not work with a welding mask.
As someone with facial hair, I can tell you that mine seals quite well (can make my ears pop if I cover the exhaust); the 3M N95s don’t seal well over a beard. There’s some breathing resistance, but not much (like using a two-hose SCUBA regulator). I’ve read that cyclists in CA have been using them to deal with smoke.
One downside is that it’s difficult to make myself understood when wearing it. Also, for a medical-reuse situation, although the filters are easy to remove/replace the elastic is fabric, which is more comfortable than rubber but is problematic if you want to dip the mask (minus filters) into sanitizing solution. It’d be nice if there were a quick way to remove/replace the straps.
The filters are ‘worn out’ when they become difficult to breathe through. I’d been using mine to deal with the cloud of dust around me when I mow the lawn on a dry day. The filters look dirty, but no restriction. I’m sure they’d go a year or more in an environment that’s not dusty. I’m not much of a ‘hoarder’ but I did buy a replacement set of filters when I first heard about community transmission in WA.
UVC cannot be used to sterilize the disposable 3M N95 masks as it degrades the filtration media, but that might not be true for these. I suspect these do not degrade under UVC, as they’re used for welding. Arc welding emits a good bit of UVC (enough to damage eyes / burn skin, which is why those hoods are used. I’ve queried GVS about this, haven’t heard back. Will update/respond if/when I do.
