Are Higher HEPA Filter Grades Always Better?

2023-10-26 10:02:16

Click：

“ Air-purification performance depends on airflow multiplied by filtration efficiency. H11-H13 filters are already highly efficient, so the best grade depends on the application. ”

Air-purification performance equals outlet airflow multiplied by filtration efficiency. This is essentially the CADR value specified in China's national standard.

Airflow: H11 > H12 > H13

Filtration efficiency: H11 < H12 < H13

The final result depends on the product of these two values. An H grade is simply a standard and a range, not a specific filter type.

Even filters with the same grade can have different resistance and airflow.

For example:

Assume that an H11 filter delivers 500 m3/h, an H12 filter delivers 450 m3/h, the H11 filter has a single-pass efficiency of 98%, and the H12 filter has a single-pass efficiency of 99.9%.

Their resulting clean-air outputs are:

H11 - 500 x 98% = 490 m3/h

H12 - 450 x 99.9% = 449.55 m3/h

A higher grade is therefore not necessarily better; the specific circumstances must be considered.

There is no need to focus excessively on grade. H11-H13 filters already provide very high filtration efficiency. For an air purifier using one of these filters, the main metric to consider is its CADR.

For ordinary indoor purification, the small difference in filtration efficiency is not especially important.

The conclusion changes when air is brought in from outdoors and the indoor environment has extremely strict requirements, such as a hospital sterile room. In that case, a higher grade is naturally preferable. The priority is not how much air can be purified in an hour, but ensuring that the incoming air is as clean as possible.

0

Long by picture save/share

Prev : How to Clean an Air Purifier Filter

Next : How Should You Interpret an Air Purifier's CADR?

Are Higher HEPA Filter Grades Always Better?

分享至微信分享

分享至微信