1. For cylinders equipped with residual (positive) pressure valves, one evacuation under vacuum at 150 millibar is sufficient if the pressure is positive.
对于装有剩余压力阀门的气瓶，如果瓶内剩余压力是正压，把它抽真空到150mbar以下就可以了；
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2. For cylinders equipped with residual (positive) pressure valves, one evacuation under vacuum at 150 millibar is sufficient if the pressure is positive.
