N95? KN95? KF94? The best is whichever fits you. I have high cheekbones & most N95s leak at my upper face. All Kf94s & most KN95s fit me perfectly, though, & I tie knots in ear loops to tighten just right. @masknerd has a great video: Fit, Fit, Fit!!!
Faces come in different shapes. (For example, most well-rated N95s leak at my nose and don't fit my cheekbones. Oft-maligned ear loop Kf94s fit me perfectly, and pass fit tests.) How to fit test masks at home:
Thread Unpacking the multiple layers of wrong assumptions: Layer 1: An implicit misunderstanding of how electret filters work - thinking that they’re like sieves rather than the overlapped sticky spiderwebs that they actually are.
Fit Testing to ensure a good seal on your mask [Part 1]
This thread explains what mask fit testing is (qualitative and quantitative), why it is important, and my testing experience with some real-world results of various types of masks including NIOSH N95 and ear loop. 🧵1/
