Symbol 3739 from ISO 7000 - Title/Meaning: Protection against CBRN (chemical, biological, radiological, nuclear) 
Function/description: To identify respiratory protective devices and components suitable for use in response to chemical, biological, radiological, or nuclear (CBRN) incidents. To indicate that the device or component meets CBRN protective requirements, particularly that filters have the necessary broad range of capability and that polymeric materials used in the device or component resist permeation by aggressive chemical warfare agents.
Own work using: iso.org/obp/graphics/grs/b368a7be-4001-4796-a600-97520b24cb0f 200.png
Vectorization:  Mrmw