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TECHNICAL DATACLASSIFICATION OF HAZARDOUS LOCATIONS812exmweb.com | 1-800-363-2423 | [email protected] of ProtectionThere are generally three methods of protection that are used to reduce the risk of explosion. Guidelines for using the most popular Methods of Hazardous ProtectionIntrinsic MethodThis method of protection has three levels. They are: \\ ic \the highest level. PreventionThis is a method that limits both the electrical and thermal energy to safe levels under both normal operation and fault conditions. Intrinsic safety is the most representative choice for this method. The first stepis to know the classification of the hazardous area under consideration. Almost every type of area has already been classified by the various governing bodies. The second stepis to choose the various types of equipment along with the method of protection that is suitable for the intended hazardous location. \ ia \intrinsic safety system offers the highest level of protection of all other protection methods. It is the safest method of protection for Zone 0 applications. That is all applications whereby there is a continuous hazardous presence. Some applications of Division 1 fall into this category. SegregationThis method attempts to physically separate or isolate the electrical parts or hot surfaces from the explosive mixture. This method includes several different techniques such as purge & pressurization, Encapsulation, etc. * Notice that every piece of equipment or method of protection that is available to increase the safety in a hazardous location should have an applicable certification indicating the Class, Group, Division or Zone to which the product has been certified to. If a product has been certified to a certain standard of protection it can then be used in any standard that requires a lesser degree of protection. \ ib \intrinsic safety system offers protection for Zone 1 applications. That is all applications whereby there is intermittent hazardous presence. Some applications of Division 1 fall into this category. Explosion containmentThis is the only method that allows the explosion to occur, but confines it to a well defined area, thus avoiding it spreading to the surrounding atmosphere. Explosionproof enclosures are based on this method. Example NEMA 7 type enclosures. \ ic \intrinsic safety system offers protection for Zone 2 applications. That is all applications whereby it is abnormal for a hazard to be present. Applications of Division 2 fall into this category.