B.1 | North American Classification of Hazardous | ||||
| Locations, Continued | ||||
Examples |
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| Given the above criteria, the following examples are made: | |||
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| • A Class III, Division 1 location is a location in which easily | ||
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| ignitable fibers or material processing combustible flyings are | ||
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| handled, manufactured or used. | ||
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| • A Class III, Division 2 location is a location in which easily | ||
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| ignitable fibers are stored or handled. | ||
Groups |
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| Flammable gases, vapors and ignitable dusts, fibers and flyings are | |||
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| classified into one of the following groups according to the energy | ||
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| required to ignite the most | ||
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| Class I | Description of Atmosphere |
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| Group |
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| A | Atmospheres containing acetylene. |
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| B | Atmospheres containing hydrogen, fuel and combustible |
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| process gases containing more than 30 percent hydrogen by |
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| volume, or gases or vapors of equivalent hazard |
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| C | Atmospheres such as ethyl ether, ethylene, or gasses or vapors |
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| of equivalent hazard. |
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| D | Atmospheres such as acetone, ammonia, benzene, butane, |
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| cyclopropane, ethanol, gasoline, hexane, methanol, methane, |
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| natural gas, naphtha, propane or gases or vapors of equivalent |
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| hazard. |
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| Class II | Description |
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| Group |
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| E | Atmospheres containing combustible metal dusts including |
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| aluminum, magnesium, and their commercial alloys, and other |
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| metals of similarly hazardous characteristics. |
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| F | Atmospheres containing combustible carbonaceous dusts |
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| including carbon black, charcoal, coal or other dusts that have |
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| been sensitized by other materials so that they present an |
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| explosion hazard. |
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| G | Atmospheres containing combustible dusts not included in |
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| Group E or F, including flour wood, grain, and other dusts of |
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| similarly hazardous characteristics. |
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84 | ST 3000 Release 300 Installation Guide | 2/05 |