正压减压装置将用于建筑排水废物和通风（DWV）系统。它们旨在减少DWV网络中因使用而产生的短时气压瞬变的影响。它们不会对空气压力的长期或稳态偏移产生任何影响。

Positive pressure reduction devices are to be used in building drainage waste and vent (DWV) systems. They are intended to reduce the impact of short duration air pressure transients which arise in DWV networks through use. They are not intended to have any effect on long duration or steady-state offsets in air pressure.