Have you noticed that the ceiling air conditioning vents in offices are usually dirty? Sometimes the ceiling around the vent shows dirt too? Residential homes have the same problem.
This was particularly noticeable a while ago when a family member visited the dentist and was staring at a dirty ceiling vent for over 30 minutes. Pristine clean environment, but the ceiling vent was grey and definitely not clean. This is a very common situation around the world.
If you see dirty vents in your premises it is simple to test for mould, follow with a sanitising clean and thereafter stop mould reinfestation. SAN-AIR specialises in providing cost-effective products that can be used by anyone to keep their indoor environments healthy for humans and pets.