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Such a location must be classified Div. 1. d. Increasing wear If a process equipment is regularly operated or worked on, it means that mechanical wear will increase. Increase in wear is normally caused by excessive operations. The rate of wear is generally accelerated by high temperatures and high pressure in the system. Increasing wear will reduce life expectancy and eventually cause leakage and/or breakdown of the equipment. For example, valves being used for a prolonged period of time in a piping system for which classification is required, may start leaking when they are subjected to excessive opening and closing cycles.

An alarm should only be applied if the enclosed space requiting a non hazardous classification is located in a Div. 2 area. An enclosed space provided with an alarm system cannot be classified nonhazardous if it is located in a Div. 1 area. The space with an alarm can only be classified n o n hazardous if it is located in a Div. 2 area. ) The likelihood that during a ventilation failure ignitable gases or vapors will enter an enclosed space, is considered greater when the enclosed space is located in a Div.

The location must be considered highly dangerous because of the continuous presence of the flammable vapors in the air and because of this, the location must be classified Div. 1. b. Closed Sources of Hazard Frequently Leaking or Opened A location is also considered highly dangerous if ignitable concentrations of gases or vapors frequently exist in a location. Flammable gases or vapors are only frequently released into the atmosphere if a closed source of hazard is frequently or continuously leaking or frequently opened because of failure, malfunction or because of repair and maintenance.