Sound insulating measures
Sound-insulating measures reduce the sound level emitted from components such as fans, filters, ducts, drive units, etc. Insulation is achieved through encapsulation (e.g., through insulating housings, insulating panels or the insulation of ducts and duct components).
Sound absorbing measures
These measures are used when openings to noise producing components cannot be avoided (e.g. noise emitted from an exhaust stack). Sound absorbers and rectangular attenuators are used. These designs are usually based on a housing with absorber material inside. The porous structure of the material extracts energy from the sound as it penetrates the material. A special form of sound absorber is the resonator, which is the preferred option when
dealing with low-frequency noises.
Measures for isolating noise from structural components
These measures include vibration dampers, expansion joints and plate-type resonators in fan units.