Defence against chemical (C) and biological (B) warfare agents roughly falls into two areas:
- - Military defence
- - Civilian defence
In the past, defence against CB weapons was almost exclusively a subject within NATO. The threat of CB weapons during the cold war came from states who were able to develop these weapons of mass destruction. CB defence was mostly aimed at protecting the military against large scale attacks.
More recently, the threat of CB terrorism has grown. As a consequence, CB defence is nowadays also aimed at protecting the civilian population and infrastructure. Knowledge of the CB (or CBRNE) threat and countermeasures is now also important for civilian first responders, who have to deal with different rules, different casualty acceptance, and a different environment than the military.