Fine and ultra‐fine powders are actively studied in pyrotechnics, explosives and propellants. The important questions are how to produce a powder with specified characteristics and how to use the powder produced.

This paper describes the technique and results of an experimental study of the ignition of condensed materials (model composite propellants) by a hot single metal particle. The dependence of the ignition delay of condensed materials (CMs) on the initial particle temperature is investigated. The mechanism of interaction of a single particle heated to high temperatures with unmetallized and metallized CMs is analyzed. It is found that the presence of a metallic filler in the CM changes the absolute values of the ignition delay and the relative characteristics of their spread.

This paper investigates the cause of ignition of wooden shields during surface fire fronts. For this purpose an experiment was conducted in which a zone 50m in length and 10m in width was chosen as the experimental site. Wooden shields (made of spruce boards) and samples of high-moor and valley peat were placed in this zone. In the experiment it was ascertained that to ensure safety during the surface fire in absence of firebrands and embers it was necessary to clear a perimeter around the zone not less than 5m in width, and remove cleared fuels. To reduce the risk of fence ignition, it was necessary to make the fences permeable. It was found that grass fires turn into peat fires if there is a conductor of combustion above the layer of peat.

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