Adopted by NATO in the early 1980s, the Marker Set, Contamination, NBC was designed to be used by soldiers in the field to mark out areas contaminated by nuclear, biological, and chemical weapons.

SOURCES:

TM 2-9905-001-10: Operator’s Manual for Market Set, Contamination: Nuclear, Biological, Chemical (NBC) (9905-12-124-5955), Headquarters, Department of the Army, August 1982

https://armychemicaloperations.tpub.com/CM7114B/Part-A-Nbc-Contamination-Markers-5.htm

https://www.groundzerobooksltd.com/pages/books/81638/united-states-army/marker-set-contamination-nbc

https://www.trngcmd.marines.mil/Portals/207/Docs/TBS/B2I0413XQ-DM CBRN.pdf?ver=2015-12-22-084156-727

https://www.scribd.com/presentation/597041914/NBC-marking-Kit

https://talesfromthesupplydepot.blog/2020/04/27/nbc-marker-signs/

https://blueshield.es/wp-content/uploads/2022/07/380180eng.pd