Because there is usually a great degree of force behind the air that shoots out of ceiling diffusers in industrial ventilation systems, these diffusers are often surrounded by turbulent air. When particles of dirt get caught up in this turbulent air, they hit the ceiling and, at least some of them, stick, creating unsightly streaks on the ceiling directly surrounding the diffuser.
Ceiling diffusers are a common element in ventilation systems, particularly in industrial buildings. These fixtures, like wall-mounted registers in residential ventilation systems, are the source from which air flows. Used in overhead ventilation systems, these elements are notorious for developing dust and becoming surrounded by smudges, potentially making them quite the eyesore. There are a number of factors that contribute to this dirt development.
Just like any other rarely touched item within a room, ceiling diffusers are prone to becoming a home for dust. Despite the fact that air shoots out of these vents, blowing off some dust, some sections of the diffuser will experience air running directly over them, allowing dust buildup to develop. This dust development is particularly common in the center of the diffuser as well as along the perimeter as neither of these areas experience much breeze.
Humidity can also play a part in diffuser dirtiness. When humidity is high, the dust that flies through the air will meet with this moisture and more easily build up on the diffuser and the surrounding ceiling. Because of this, areas that often experience high humidity may also be home to generally dirtier diffusers.
The manner in which the room featuring the diffuser is used will contribute greatly to how dirty the diffuser becomes. Rooms in which dust and dirt are plentiful, such as copy rooms where toner often escapes into the air or storage spaces in which dust commonly settles, will likely have dirtier diffusers than rooms in which these dirt sources aren't present. Because dirty diffusers can lead to poor air quality, cleaning diffusers when they acquire dirt is a wise choice.