HC Replacement Research

A number of research programs have been carried out in recent years in efforts to develop white smoke screening compositions to replace HC smoke that are low in toxicity and meet aU of the other requiranents for a good pyrotechnic smoke. This 

FIGU RE 9.2 The chemical structure of terephthalic acid, used for the production of low toxicity, white smoke. 

While the TA (for terephthalic acid) smokes cannot match the HC smokes in obscuration on a pound-for-ponnd basis, it may well tnm ont to be the case that smoke devices for use in training will contain a low-toxicity composition like the TA smoke mixture, and the more highly obscuring HC smokes are reserved for use in true battlefield conditions. 

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