US ARMY SCIENTISTS DEVELOPING NEW SMOKESCREEN COMPOSITIONS

Scientists from the US Army’s Edgewood Chemical Biological Center (ECBC) are developing new smokescreen compositions to help soldiers effectively mask themselves from enemy fire. Developed under a multi-year programme, the new formula is expected to replace the army’s World War II-era MP2S-HC screening smoke grenade, which delivers a dense cloud of grey hexachloroethane smoke with a discharge time of 100 seconds. The scientists are currently considering four basic smoke compositions, the first of which is a zinc-free composition, HX, which is similar to the hexachloroethane composition but doesn’t generate a toxic, irritant smoke containing zinc chloride. ECBC Pyrotechnics and Explosives Branch senior engineer Joseph Domanico said the chemical reaction of the HX composition produces slightly less combustion products and has a higher efficiency, which results in a similarly dense smoke cloud. The second hexachloroethane-free composition encapsulates chlorine atoms in a plastic matrix, which are subsequently freed by the heat of combustion, enabling the smoke to pull water from the atmosphere, thus producing a dense smoke cloud.