True: I had hoped that I was showing what minimal effect a current service respirator would have at this time.Blood agents and NP are not biological agents.
The most common blood agent was Hydrogen cyanide (CK). The reason the canister life was only 30 mins is that it destroys the canister filling, removing any protection, with no advanced warning.
Unless a civvy was prepared to adopt either 3R or a closed air breathing system and HAZMAT rig.
. . . and follow the fully approved HO decontam and casualty handling regime for a CBRN event (admittedly, with an emphasis on the 'N' bit).