Air purifier core index: clean air output ratio CADR
CADR (Chinese name for clean air output ratio) refers to the rate of clean air output from an air purifier determined by the Association of American Home Appliance Manufacturers (AHAM) according to strict testing standards. The higher the CADR value, the higher the purification efficiency of the purifier.
In order to make the indoor air quality reach a certain clean standard, air purifier has two necessary hard indicators, 1, must ensure that the indoor air reaches a certain number of ventilation (international is 5 times); 2. The primary purification efficiency of the air purifier must be relatively high. If indoor pollution sources continue to produce, the two hard indicators of the air purifier can make indoor pollutants maintained at a lower concentration.
First, it is necessary to ensure that the indoor air reaches a certain number of ventilation, that is, the built-in fan of the air purifier is required to have a certain air volume. The international standard is to ensure 5 air changes per hour in the applicable area.
Take an air purifier as an example:
The formula for calculating the applicable area of air purifier is as follows:
Applicable area S (square meter) =12F/60H
Among them:
Filter 5 times per hour, that is, every 12 minutes;
F= the maximum air output of the air purifier, the unit is cubic meters/hour;
H= the height of the room, generally 2.8 meters.
For example: an air purifier, the maximum air output F is 400 cubic meters/hour, calculate the applicable area S of the air purifier is:
S= 12×400/ (60*2.8) =28.57 square meters
If the effective volume of the room and other factors are considered, the room area of the air purifier is about 30 square meters.
Two, the primary purification efficiency of the air purifier must be relatively high. The higher the purification efficiency (CADR), the better the air purifier is There are three indicators of purification efficiency (CADR) value:
1. Dust;
2. Second-hand Smoke.
Pollen.
CADR value is a physical quantity that can quantitatively express the above two necessary conditions of air purifier.
The higher the CADR value, the higher the purification efficiency of the air purifier. The CADR value can be used to evaluate the effect of air purifiers on removing indoor air pollutants after a certain period of operation.
If indoor pollution sources continue to arise, the use of air purifiers with high CADR values can keep indoor pollutants at a lower concentration.
Purification efficiency η
Purification energy efficiency (η) refers to the amount of clean air that an air purifier can produce per unit power consumption, in cubic meters per hour watts (m³/ (W ·h)).
The National Household Appliance Quality Supervision and Inspection Center has introduced that the national standard GB/T18801-2015 will be divided into high efficiency and qualified level of purification energy efficiency. The evaluation of purification energy efficiency on the performance of purifiers is more comprehensive than CADR, making purifiers of different grades comparable. In general, the greater the value of purification energy efficiency, the better the purifier is, and it is the first choice of consumers. The new national standard stipulates that 2 or more are qualified, and 5 or more are efficient. The greater the value, the more efficient the air purifier is. Generally speaking, when the purification energy efficiency of gaseous pollutants of the product is lower than 0.1 m³/(W·h), the purification effect of the product on the pollutant is not obvious.
In addition, when choosing air purifier, we also need to pay attention to:
1. When buying, we should also understand the convenience of after-sale service. Include installation, whole machine guarantee time (1 to 2 years have), the cleaning of the product, filter net, change and change the cost of filter net, filter net whether to buy convenient and so on.
2. To purchase vehicular air purifier products through regular sales channels, ask for invoices and warranty tickets, in order to prepare for future maintenance and rights protection.