The coronavirus particles are so small they go right through the filter so N95 masks have special fibers that use electrostatic charge to bind them. The electro

The coronavirus particles are so small they go right through the filter so N95 masks have special fibers that use electrostatic charge to bind them. The electrostatic filter doesn't work effectively when damp, eg after prolonged exposure to humid breath. There's an incredible amount of engineering that goes into PPE.