How to measure air volume at HEPA Box

High-efficiency air outlets are ideal terminal filtration devices and are widely used in the pharmaceutical, health, electronics, chemical and other industries. In order to verify whether the clean room can meet the cleanliness requirements, it is necessary to test the clean room and high-efficiency air outlets, so its detection is very important.

 How to measure the air volume of high-efficiency air outlets: 

1. You can use the air volume hood to directly aim at the nozzle for one-time measurement. Since your nozzle has many small holes (to make the air volume uniform) and there is a grille, then your anemometer can be kept 3-5 cm away from the nozzle. If you have a thermal anemometer, try to face the gap instead of the grille, and measure the average value by the grid method. The same cross-section can be measured.

2. You can measure at multiple points at a distance of 2 times the width of the diffuser from the air outlet. The measuring points should be like a grid and then the wind speed is averaged. The sizes of these vents are similar. Use tinplate or even plastic plate to make a barrel that is slightly larger than the cross-section of the air outlet, and then cover the barrel on the air outlet when measuring, and then use the anemometer to measure the nozzle of the barrel at multiple points and calculate the average value.

3. Clean air can be obtained through the clean air conditioning circulation fan, high-efficiency air filter, medium-efficiency filter, and primary air filter. The cleanliness is different, and the wind flow direction is different. Of course, it is also necessary to supplement some fresh air through the fresh air outlet, otherwise people will feel stuffy inside.

 Air volume measurement of high-efficiency air outlet: 

1. The detection method of high-efficiency air outlet uses active sampling and passive sampling. Active sampling uses filtering method and impact method. The filtering method allows a certain amount of air to pass through an analytical filter.

2. The impact method can use Anderson sampler, Lute centrifugal sampler, and slit sampler. Passive sampling uses the landing method. The principle of diffusion of open agar plates with suspended particles is used.

3. Of course, with the development of science and technology today, some more sophisticated detection instruments can also be used to quickly detect it.