Flame arrester types generally

Type II Flame arresters acceptable for in-line applications. Type II arresters shall be specifically tested widi the inclnsion of all pipes, tees, bends, cowls, weather hoods, etc., which may be fitted between die arrester and the atmosphere. Owing to the prohibitive cost of testing deflagration flame arresters for each particular installation, the Type II (in-line) category is generally not enconntered. 

Flame arresters are fitted in the vent lines of equipment that contains flammable material to prevent the propagation of flame through the vents. Various types of proprietary flame arresters are used. In general, they work on the principle of providing a heat sink, usually expanded metal grids or plates, to dissipate the heat of the flame. Flame arrestors and their applications are discussed by Rogowski (1980), Howard (1992) and Mendoza et al. (1988). 

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