Industrial Fan Noise: Case Study

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A manufacturing plant contacted Unger Technologies to review noise exposure from several of its variable frequency belt driven centrifugal fans.

We conducted sound level readings around the Chicago Blowers and noted low and mid frequency levels between 90-91 dB(A) 5 feet from the fans.

Our client expressed a need to access the machines for routine maintenance. They also did not desire a full sound enclosure because of ventilation and lighting concerns.


Blower casing shown with Unger's removable sound blanket (click image for larger view)	Fan shown with sliding access sound curtain (click image for larger view)

Unger determined noise sources associated with this fan where the variable speed driven motors and the fan casings. The variable speed drives where re-tuned by the equipment supplier with little reduction in noise. After this option was tried, Unger suggested a removable sound blanket wrap be installed on the fan housing and then a perimeter sound curtain system be installed.

We supplied our rugged industrial sound curtains with a ceiling suspended steel track. We engineered modular sliding sound curtain panels on a double track to allow the customer multiple access points in the enclosure.

The sound reduction was measured at 12 decibels thus achieving the customers acoustic goals well below 85 dBA.

Modular sound curtains used on
double sliding track
(click image for larger view)

Please call Unger Technologies for your industrial fan noise problems.