Do not store full and empty cylinders together.

禁止把满瓶和空瓶存放在一起。

youdao

When returning empty cylinders, close the valve before shipment. Leave some positive pressure in the cylinder.

返还空瓶时，在运输之前关闭阀门，使钢瓶内部保持 正压 。

youdao

The process is expensive and lengthy, and includes bringing all non-disposables, like batteries and empty oxygen cylinders, back to Kathmandu and on to their home countries.

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There were no reports of injuries in the fire, and many of the 240 cylinders involved were believed to be empty.

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