the sentence
Quote:
This mean, you either have to wear it all the time or accept the risk.
was only ment as for the biological attacks.

As for the part about dust created by blast and fire, that is really a question you have to ask your self when it happends. No terrorist attack is identical, therefor you can't have a fixed protocol for wearing or not wearing a mask. The availible ventilation and exit routs vary from place.
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