The best system is called an SCBA (self-contained breathing apparatus) system.

最好的呼吸器系统称为scba(自给式呼吸器)系统。

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Personnel, including rescue workers, should not enter areas where the oxygen concentration is below19.5%, unless provided with a self-contained breathing apparatus (SCBA) or airline respirator.

除非备有自己式呼吸器（SCBA）或空气管呼吸器，任何人，包括救援人员，都不能进入氧浓度低于19.5%的区域。

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Specific PPE, including acid suits and self-contained breathing apparatus (SCBA), may be required if the cylinder must be approached.

如果必须接近钢瓶，要求穿戴特殊的PPE，包括防酸服和自给式呼吸器(SCBA)。

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