摘要 |
In this pack there are fixed requirements for the cross-section of the outlet opening of the shut-off device, for the ratio of the cross-section of a vapour emergence opening of the shut-off device to that of the immersion tube end piece or to the internal cross-section of the immersion tube, and the sedimentation volume of a spraying agent containing a suspended powder. If these requirements are met there is a reduction in the proportion, arising on spraying the spraying agent, of those constituents which are inhaled by people and deposited in their lungs. |