The double chamber measurement method based on AMCA standard 210 conforms to JIS standard. The reason for this is that there is evidence to show that the Chater method can be used. In the following explanation, the air flow test method and measurement specification are introduced,

The radiator fan to be inspected is placed at the entrance of the equipment, between the independent Airflo measuring nozzles. The air flow through the nozzle can be calculated by measuring the pressure gap between the front and rear of the nozzle. At the same time, the static pressure generated by the cooling fan can be measured. The function of the auxiliary fan is to measure the air flow through the gap pressure before and after the nozzle when there is no difference between the front and rear pressure of the fan.

First, close all nozzles and measure the maximum static pressure by closing the fixed air holes on the side of the measuring fan. Secondly, release the nozzle to automatically control the auxiliary cooling fan without pressure damage. Then calculate the maximum air flow between the pressure between the air holes and the diameter of the nozzle, and measure the airflow and static pressure of the measured point. This is specified by measuring the air flow, and the auxiliary cooling fan is used to make the air flow report,