3 ms·
This is like theoretically true but mostly useless. There is filtration beyond even HEPA. For example, MERV-20 is 99.9999% efficient at 0.1->0.2um particle size
by DannyBee 5y ago
This is like theoretically true but mostly useless.
There is filtration beyond even HEPA.
For example, MERV-20 is 99.9999% efficient at 0.1->0.2um particle sizes.
It is 99.99% efficient at particle sizes like 0.01um.
The bigger issue is not whether you can get filters to do it, it's whether your system was built for the pressure drop you'd need to do it.
IE UV's advantage is that it doesn't really drop pressure (but does require some dwell time), not that you can't filter air well enough.
- bradknowles 5y agoI was referring to standalone systems that are designed to filter all the air in a room, and use so-called “HyperHEPA” filters to get particles way below the size that HEPA is designed for. Of course you can also get higher filtration rating filters to attach to your whole-house air handling units, and — as you point out — those would have to be sized and designed for that. But the whole house units weren’t what I was talking about.