Currently, most AHUs Possess a secondary filter and that is possibly an electronic air filter or bag filter that has a filtration grade of all over F9 or MERV13. This kind of filtration quality not just protects the AHUs and also gives cleaner air for that folks. What about humidity https://andywphxm.csublogs.com/38693196/air-handling-units-ahus-things-to-know-before-you-buy