Noise

Sound output to duct

In most cases, a ventilation system needs silencers to ensure a low sound level in the room of use. To permit dimensioning of silencers, measurements are taken throughout the operating range, and the measured values are included in product information together with detailed description of how this data is to be used. Measurements are made in accordance with ISO5136.
Data is shown in product information and printouts from calculation programs.

Sound output to surroundings

In this case, sound is measured at a number of virtual points round a unit, with measurements throughout the operating range. The measured values are included in product information together with a detailed description of how this data is to be used. 

When measuring a product with a very low noise level, measurements are taken in a special sound laboratory– see photo.
Measurements are made in accordance with ISO3744 (ISO9614 in the case of VEX300C).

Data is shown in product information and printouts from calculation programs.


Assumptions for sound data
You can read more about the assumptions under which sound data is measured. This will enable you to compare our product data with that of our competitors.

You can find a description of assumptions for sound data in respect of: