Smoke, military

Smoke -military screening [PHOSPHORIC ACID AND PHOSPHATES] (Vol 18)... 

Smoke, Military. See under Pyrotechnics in Vol 8, P507-L to P508-R (Colored and White Smoke, Screening Smoke, Signal Smokes)... 

Military Application and Aerospace Wires. Depending on the specific appHcation, a variety of polymers can be considered PVC, polyamides, PTEE, etc (Eig. 3). Navy shipboard specifications require cables with dame retardancy, low smoke emission during fire, and containing no halogen. 

Smoke-Generating Devices. Smoke generators are used by the military for daytime obscuration and signaling. For field use where portable stable systems ate requited, pyrotechnic devices are often employed. The primary composition since the 1940s has been HC smoke, which generates a cloud of zinc chloride, ZnCl, smoke by a series of reactions between hexachloroethane, C2Clg(HC), zinc oxide, and aluminum (3) (eq. 4—6). The zinc regenerated in... 

Refs 1) R.P. Teele HJK. Hammond, Development of a Laboratory Test for Evaluation of the Effectiveness of Smoke Signals , NBS Rept 4742 (1956) 2) Anon, Military Chemis-... 

Red P has been employed as an ingredient of pyrotechnic smoke, delay and safety match formulations (Refs 1,2,3 4). White smoke consisting of small droplets of phosphoric acid have been widely used for military purposes. 

The pyrotechnic generation of smoke is almost exclusively a military device for screening and signaling. While first encountered on a significant scale in WWI, its importance was not realized until early in WW1I when the bulk of the presently known data were collected. In the last 30 years studies of smoke have continued at a reduced rate... 

Poly(aryloxyphosphazene) elastomers can be cured with peroxides, sulfur and radiation. The resulting vulcanizates are resistant to attack by moisture and oils and have been found to have desirable characteristics for electrical insulation applications where fire safety is a concern (Table II) (12). Fire resistant, low smoke, closed cell foams with excellent properties (Table III) have also been developed from poly(aryloxyphosphazene) elastomers (13). Applications for these foams, which can be produced as either slabstock or tube stock, are being developed for military, aerospace and commercial uses. (See Table II and III.)... 

Toxicity of Military Smokes and Obscurants, Volume 1 (1997), Volume 2 (1999), Volume 3 (1999)... 

Phosphorus pentoxide reacts with moisture in the air to form phosphoric acid. WP munitions were used by U.S. military forces and their allies to mark targets and to provide smoke screen coverage for troops and equipment in combat zones. These munitions were produced primarily by the dip-fill or wet-fill method illustrated by Figure 1. The method is called dip-fill because empty munition bodies are dipped below the molten phosphorus level in an open tank until the munitions are filled with liquid phosphorus. The method is also called wet-fill because a water overlay is maintained over the liquid phosphorus (in the fill tank) to prevent spontaneous combustion of the chemical element and because the filled munition will have a slight water overlay (up to 1/8" column height allowed). 

Hexachloroethane is a colorless solid that gradually evaporates when it is exposed to air. This compound is also called perchloroethane, carbon hexachloride, and HCE. It is sold under the trade names Avlothane, Distokal, Distopan, and Distopin. In the United States, about half of the hexachloroethane is used by the military for smoke-producing devices. It is also sold as degassing pellets that are used to remove the air bubbles in melted aluminum. Hexachloroethane may be present as an ingredient in some fungicides, insecticides, lubricants, plastics, and cellulose. At one time, hexachloroethane was prescribed for deworming animals. 

Hexachloroethane is released to the air during military operations and training exercises when smoke-producing devices containing it are used. In a smoke pot or grenade, most of it is used up by the smoke-producing reaction. Only small amounts (5% or less) remain after the smoke has formed. 

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