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Subchapter 7. General Industry Safety Orders
Group 20. Flammable Liquids, Gases and Vapors
Article 142. Industrial Plants

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§5549. Sources of Ignition.

(a) Adequate precautions shall be taken to prevent the ignition of flammable vapors by open flames; lightning; smoking; cutting and welding; hot surfaces; frictional heat; static, electrical and mechanical sparks; spontaneous ignition, including heat-producing chemical reactions; radiant heat; or other sources of ignition.

(b) Class I liquids shall not be dispensed into metal containers unless the nozzle or fill pipe is in electrical contact with the container. This can be accomplished by maintaining metallic contact during filling, by a bond wire between them, or by other conductive path having an electrical resistance not greater than 106 ohms. Bonding is not required where a container is filled through a closed system, or the container is made of glass or other nonconducting material.

(c) See Article 140 for electrical classifications.

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