Air filter cleaning practice: who is correct?

• A. Technician A
• B. Technician B
• C. Both A and B
• D. Neither Technician A nor Technician B

Answer: (D)

The important idea here is when to clean versus replace an air filter. In most systems, disposable filters are not meant to be cleaned at all. Cleaning can leave fine particles embedded in the media, reduce filtration efficiency, and can damage or deform the filter so it doesn’t seal properly, which lets unfiltered air bypass the filter. Even when a filter looks dirty, the safer, more reliable practice is to replace it.

If a filter is designed to be cleaned and the manufacturer provides explicit instructions, then cleaning must be done exactly as specified, using the approved method and ensuring the filter is completely dry and undamaged before reinstalling. In situations where the filter isn’t approved for cleaning, or the proper procedure isn’t followed, the maintenance performed isn’t considered correct.

So, since neither technician followed the appropriate replacement-or-manufacturer-approved-cleaning procedure, the correct approach is that neither is correct.