Not completely ineffective, but ineffective at filtering the designed 95%. Here’s NIOSH’s page [0] defining fit testing and why it’s important. You don’t see this warning because it’s on NIOSH’s site, just like you don’t see the definition of all the stuff and just have the certification is for your test.
Some masks are just incompatible with some faces, it’s greaT that Aura’s have an instruction video, that doesn’t mean it will work for all people.
> An ill-fit N95 that might not be perfectly adjusted to conform is still way better than a cloth mask which isn't intended to seal at all.
I think you’re probably right. But I don’t know of a study that tests this because N95s are measured as conforming to spec, not when they are worn improperly without a seal at the nose and chin. I hope we get some info on this.
The Dirextors (and Fauci’s) comments weren’t about this though, they mentioned how N95s are uncomfortable and thus hard to wear consistently. Try wearing an N95 for 6 hours of school. Especially without training. I think the recommendation for cloth masks is because of the ability for people to wear them.
So the recommendation is not based around optimal standards of use, but around likely use.
This doesn’t mean that N95s don’t protect people. I wear them in public. I’m just trying to correct GP’s criticism that someone the CDC director’s comments are incorrect or illogical.
[0] https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part...