Can an increased safety type junction box be placed in Zone II?
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Excuse me, sir. There’s a wiring box for a flammable gas area alarm in Zone II. Is it permissible to use an increased-safety type of wiring box there?
For electrical equipment in factories, Zone 2, enhanced safety type can be used. The wording should be clear, and the description accurate. There is no such term as “Zone II”; only “Category II” is used.
This “II” refers to the classification of hazardous locations based on explosive and combustible atmospheres; it should not be referred to as “Zone II”. Zone 2 refers to the probability of the presence of an explosive and combustible atmosphere; it corresponds to Zone 1 and Zone 0. In Zone 2, essentially any type of explosion-proof instrument junction box can be used, including the Ex n type that is non-sparking.