一个动火证只适用一个班次的作业，最多一天有效。

V one permit should never be valid more than of one working shift.

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受限空间内的所有动火作业必须要有动火作业许可证和受限空间作业许可证及作业危险性分析。

All hot work in confined space must have work Permits of the hot work and confined space and Job Hazard Analysis.

youdao

办理作业许可证才能进行动火作业。

Get a work Permit before you can start the hot work.

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