Diphosgene (DP) pulmonary/choking agent

Diphosgene DP is a colorless vapor at normal temperatures. It has the odor of new-mown hay or grass, or of green corn. It causes tears (lacrimatory), which reduces its surprise value. Intended for use as a delayed-action casualty agent. Diphosgene is a combination of phosgene and chloroform. It must be carried in glass containers (instead of metal).

Choking agents injure the unprotected human chiefly in the respiratory tract, i.e., the nose, throat and lungs. In extreme cases,...