Nerve agents binary weapons

Uhe stockpile (the subject of the Amy s Chemical Stockpile Disposal Program) consists of (1) bulk containers of nerve and blister agents and (2) munitions, including rockets, mines, bombs, projectiles, and spray tanks, loaded with nerve or blister agents. Buried chemical warfare materiel, recovered chemical warfare materiel, binary weapons (in which two nonlethal components are mixed after firing to yield a lethal nerve agent), former production facilities, and miscellaneous chemical warfare materiel are not included in the stockpile. The disposition of these five classes of materials is the subject of a separate Non-Stockpile Chemical Materiel Pro-... 

So-called "binary" weapons have been developed. The idea behind these is that two relatively non-toxic chemicals are placed in separate compartments in a shell. On firing these mix — perhaps by rupture of a bursting disk — and then are further mixed by the rotation of the shell in flight, so that the actual nerve agent is formed after the shell has been fired. For example, with Sarin (see above) methylphosphonic difluoride (CHgPOF ) and a mixture of isopropyl alcohol and isopropylamine (this catalyses the reaction) could be the two components. However, methylphosphonic difluoride is far from being non-toxic and the main advantage, in fact, seems to be that the separate components are easier to store and transport than Sarin itself. 

J.P. Perry Robinson, Binary Nerve Gas Weapons in SIPRI, Chemical Disarmament New Weapons for Old, p. 26. The Soviet Union defines binaries differently - as a cocktail of different chemical warfare agents, rather than the precursors of an existing agent. See J. Hemsley, op. 

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