The dark gray halo around a ceiling diffuser is the visible edge of a much larger problem. Dust that accumulates on register vanes gets re-suspended into breathing air every time the system cycles. Regular vent cleaning is one of the highest-ROI IAQ investments an office can make.
Recommended Frequency
- Supply diffusers: HEPA-vacuum quarterly, wet-wipe semi-annually.
- Return grilles: HEPA-vacuum monthly, wet-wipe quarterly.
- Filter grille faces: HEPA-vacuum at every filter change (usually quarterly).
- Full duct cleaning: every 3-5 years by a NADCA-certified specialist.
The Right Method
A duster or dry rag only smears dust and pushes it into the airstream. Use HEPA-filtered vacuum with a soft brush attachment, then follow with a microfiber wipe dampened in neutral cleaner. Never spray water directly into a live diffuser.
When to Call an IAQ Specialist
Visible mold, persistent musty odor, or tenant health complaints require a NADCA-certified duct cleaning firm — not a janitorial provider. Cleaning the visible register won't fix contamination inside the ductwork.
Add Vent Cleaning to Your Program
We include quarterly HEPA vent cleaning in most office contracts — no separate PO required.