Yellow Zone : Areas where contamination with chemical, biological, radiological, or nuclear (CBRN) agents is possible but active release has ended and initial monitoring exists
National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention (CDC), The Emergency Response Safety and Health Database, Atlanta, GA, USA 2014. http://www.cdc.gov/NIOSH/ershdb/glossary.html#B, (Emr Resp Sfty and Hlth Database - Amer) {794}