Cause and prevention of dust explosions in grain elevators and flour mills

Grain and flour dusts can form explosive clouds and, because explosions from such clouds have caused some of the worst industrial accidents, it is necessary to draw public attention to this problem. Statistics of dust explosions in the United States show that more than 50% of all explosions of combustible dusts have occurred in grain elevators and flour mills. Dusts from wheat and other grains, as well as from flour, ignite and propagate flames readily because the source of heat required is relatively small. The author analyzes conditions and causes of dust explosions to determine critical concentrations of dust and air and the temperatures necessary to ignite an explosion. He describes the effect and destruction of dust explosions in examples of recent disasters in the United States and Europe and recommends preventive measures, as well as structural features of building and plant, to avoid the many injuries and deaths, as well as material losses worth millions of dollars, resulting from such explosions.