CADR, short for Clean Air Delivery Rate, refers to the rate at which a purifier delivers clean air.
It is the core indicator for measuring an air purifier’s actual purification capability, with the unit m³/h. This figure directly answers the question users care about most: how many cubic meters of clean air can this machine deliver per hour.
CADR is divided into two categories:
Particulate matter CADR: purification capability against solid particulate matter such as PM2.5, dust, and smoke
Formaldehyde CADR: purification capability against gaseous pollutants such as formaldehyde and TVOC
How to determine the applicable area using CADR?
According to the national standard GB/T 18801-2022, there is a simplified calculation formula for the applicable area: applicable area ≈ particulate matter CADR × 0.12. For example, a purifier with a particulate matter CADR of 1200m³/h has a theoretical applicable area of about 144㎡.
However, it should be noted that this formula is based on the assumption of a continuous pollution source indoors. In actual commercial scenarios, pollution source intensity is higher, ceiling heights are greater, and foot traffic is more frequent, so the actual applicable area often needs to be estimated somewhat conservatively.
Three details easily overlooked when looking at CADR values:
Whether the CADR is a measured value or a nominal value: The CADR claimed by some brands has not been tested by third-party laboratories. Only test reports from laboratories with CNAS/CMA accreditation have reference value.
The balance between CADR and noise: A high CADR often comes with a high fan speed, and a high fan speed means greater noise. A good purifier needs to strike a practical balance between clean air output and operating sound.
The CADR decay curve: The filter gradually becomes saturated during use, and the CADR declines accordingly. The greater the filter’s dust-holding capacity, the longer the CADR stays at a high level.
When designing the Y series products, YifeiAir prioritizes filter dust-holding capacity and air duct efficiency rather than simply pursuing peak CADR figures. This is because what we care more about is whether, after several months of continuous operation in commercial scenarios, the device’s actual clean air output can still meet the needs of the space.
