Here's how we test air purifiers.
Performance
Our air purifiers performance test is based on the clean air delivery rate (CADR) industry standard test for air purifiers.
We test air purifiers on their highest fan setting to see how quickly and effectively they remove particles of dust, smoke and volatile organic compounds (VOCs) from the air. VOCs are emitted as gases from solids or liquids, including paints, cleaning products, pesticides, building materials, glues, marker pens and photocopiers.
We use fine particles of titanium dioxide to test dust removal. We burn wood chips to test smoke removal, and we use acetone to test VOC removal.
We introduce these pollutants in a controlled way into the test chamber and mix them into the air.
First, we measure how fast these air contaminants naturally dissipate or decay in the air without the air purifier running. Then we clear the chamber and repeat the test with the air purifier running.
We calculate the percentage of particles the air purifier has removed and compare this with the natural decay rate measured without the air purifier running. This tells us how quickly and effectively the air purifier is clearing the air.
Ease of use
For ease of use, we assess how easy the air purifier's controls are to use and the clarity of their labelling, the stability of the unit, the ease of lifting and moving the unit, the ease of cleaning the unit, and whether it has cord storage.
Noise
We record the noise levels in decibels (dBA) produced on the highest fan setting, so you can compare which air purifiers are quietest.
Daily running cost
We calculate the daily running cost of each air purifier, running for 12 hours, based on the energy used (kWh) and current price of electricity.
Other functions and features
We make a note of any additional functions and features each air purifier has, such as heating and cooling, and additional filters.
