Of course the presence of humans themselves also changes the odds of fire, as people are a frequent source of ignition—both accidental and deliberate.

当然，人类自身的存在也改变火灾的可能性，因为人类是一个经常地导火源——有无意的也有故意的。

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Personnel should stay in a well-ventilated area and avoid any source of ignition until their clothing is completely free of any excess oxygen.

人员应一直呆在通风良好的区域，避开任何火源，直到他们的衣物彻底没有任何多余的氧为止。

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This is another area where the tool can be the source of the spark or heat causing ignition of flammable materials.

这是工具可能成为火花源或热源并点燃可燃物的又一类区域。

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As part of their investigation, Japanese and U.S. experts want to determine if an internal battery failure, or defective lithium-ion cell, was the ignition source in either of the two incidents.

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