I live five miles from one of the largest concentrations of nerve gas in the US. The rockets are disintegrating and the experts and want to be experts are arguing as to how to dispose of them as they continue to disintegrate. So I have NBC masks. The community has a good warning system if there is an accident at the Depot. The planned evacuation system isn't trustworthy because everyone will be running into each other at the interesections in panics. I'm sealing up with the masks, assuming I'm home. The masks I have pull over the head and the fit is assured. You can wear eyeglasses underneath. I'll find the website and link later.