In the majority of rooms, the most common source of disturbing noise is mechanical system noise or HVAC noise. Here are some factors to be considered when designing different installations for buildings:
- The location of different machinery and HVAC equipment in a building should be chosen well at the beginning of the building design.
- HVAC equipment should be carefully selected with low sound input levels.
- All the possible vibrations from the equipment should be isolated.
- Fan noise should be insulated with silencers.
Here is an example of sound attenuation in a 500 mm rectangular duct: