Formulations
In its history, various types and mixtures of sulfur mustard have been employed. These include:
- H – Also known as HS ("Hun Stuff") or Levinstein mustard. This is named after the inventor of the quick but dirty Levinstein Process for manufacture, reacting dry ethylene with sulfur monochloride under controlled conditions. Undistilled sulfur mustard contains 20–30% impurities, for which reason it does not store as well as HD. Also, as it decomposes, it increases in vapor pressure, making the munition it is contained in likely to split, especially along a seam, releasing the agent to the atmosphere
- HD – Codenamed Pyro by the British, and Distilled Mustard by the US. Distilled sulfur mustard (bis(2-chloroethyl) sulfide); approximately 96% pure. The term "mustard gas" usually refers to this variety of sulfur mustard. A much-used path of synthesis was based upon the reaction of thiodiglycol with hydrochloric acid.
- HT – Codenamed Runcol by the British, and Mustard T- mixture by the US. A mixture of 60% sulfur mustard (HD) and 40% T (bis ether), a related vesicant with lower freezing point, lower volatility and similar vesicant characteristics.
- HL – A blend of distilled mustard (HD) and Lewisite (L), originally intended for use in winter conditions due to its lower freezing point compared to the pure substances. The Lewisite component of HL was used as a form of antifreeze.
- HQ – A blend of distilled mustard (HD) and sesquimustard (Q) (Gates and Moore 1946).
Read more about this topic: Mustard Gas