净化效率（CADR）值有三项指标：
The purification efficiency (CADR) value has three indicators:
1、固态颗粒物，又称粉尘 (Particle)，国内通常用香烟来模拟，所以又称烟尘
1. Solid particulate matter, also known as Particle, is usually simulated by cigarettes in China, so it is also called smoke and dust.
2、挥发性有机物 (VOC)，通常用甲苯作为测试源
2. Volatile Organic Compounds (VOC), usually using toluene as test source
3、甲醛 (formaldehyde)
3. Formaldehyde
由于一般的空气净化器对于粉尘的去处效果非常明显，而对挥发性有机物和甲醛的去处效果则不如粉尘，所以很多商家仅标示粉尘的CADR。
Because the general air purifier has a very obvious effect on dust removal, but the effect on volatile organic compounds and formaldehyde removal is not as good as dust, so many businesses only label the dust CAD R.