Tear Agent - CNB

Persistency Varies, depending upon amount of contamination and form 

Use Training and riot control limited tactical use in counter- 

The symbol CNB identifies a mixture of 10% CN, 45% carbon tetrachloride, and 45% benzene. It is a powerful lacrimator. US forces adopted CNB in 1920 and used it until CNS replaced it. The advantage claimed for CNB was that its lower CN content made it more satisfactory than CNC for training purposes. Actually, merely using a lower concentration would obtain the same result with CNC. 

Mixture [not available] chloroacetophenone [532-27-4] carbon tetrachloride [56-23-5] benzene [71-43-2], 

CNB is a slightly brown liquid Smells heavily of benzene C8H7C10 CC14 C6H6 154.59 154 78 

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