净化是指清除不需要或有害的杂质，使物品达到纯净的程度。在一定空间范围内，将空气中的微粒子、有害空气、细菌等污染物排除，并将室内温度、洁净度、压力、气流速度与气流分布、噪音振动及照明、静电控制在某一需求范围内的工程学科。空气净化器(又称为室内空气净化器)广泛应用于空调房间如办公室、宾馆、民用住宅、医院病房以及其他需要净化空气的实验室、计算机房等场所，它对于改善室内的空气质量大为有益。
Purification refers to the removal of unnecessary or harmful impurities, so that the goods can reach the level of purity. In a certain space, it is an engineering discipline that removes the air particles, harmful air, bacteria and other pollutants, and controls the indoor temperature, cleanliness, pressure, air velocity and air distribution, noise, vibration, lighting and static electricity within a certain demand range. Air purifier (also known as indoor air purifier) is widely used in air-conditioned rooms such as offices, hotels, residential buildings, hospital wards and other places where air purification is needed, such as laboratories and computer rooms. It is very beneficial to improve indoor air quality.