Chemical, biological, radiological and nuclear defense (CBRN defense or CBRNE defense) are protective measures taken in situations in which chemical, biological, radiological or nuclear warfare (including terrorism) hazards may be present. CBRN defense consists of CBRN passive protection, contamination avoidance and CBRN mitigation.
A CBRN incident differs from a hazardous material incident in both scope (i.e., CBRN can be a mass casualty situation) and intent. CBRN incidents are responded to under the assumption that they are intentional and malicious; evidence preservation and perpetrator apprehension are of greater concern than with HAZMAT incidents.
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