Toxic and Flammable Gas detectors
A continuous gas (or fire or heat detector) is one that is installed and as named, works all the time. Any time the level of gas exceeds the specified threshold, it initites a signal. This signal in turn may trigger a visual and/or audio alarm, or initiate an executive action like opening the deluge valve and sprinkler system, or shut down a facility.
A spot detector is used to measure the present level of gas intensity. If it is below the threshold, a decision to permit some work may be taken. Typically, if you want to cut or weld or do other work that may initiate a fire, you want to ensure that the place is free of gas. Generally these detectors are portable, and used in conjunction with Permit to Work systems.
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