NIOSH Mining Laboratory

The Hemi-Anechoic Chamber

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The PRL Hemi-Anechoic Chamber is used primarily for noise source identification (NSID) to help target noise control efforts. The chamber has Eckel Supersoft Panels on the walls and ceiling to yield a virtual free-field over a reflecting plane (the hard floor). The interior dimensions of the room are approximately 16.7 meters long by 10.1 meters wide by 7.0 meters high yielding a volume of approximately 1200 cubic meters. The chamber meets the requirements of the ISO 3744 standard down to approximately 100 Hz. The Hemi-Anechoic Chamber is equipped with a Bruel & Kjaer Pulse data acquisition system with 46 inputs and 2 output channels and a 42-microphone Bruel & Kjaer beamforming array. The array is used in this chamber to perform NSID. In addition to NSID testing, the Hemi-Anechoic Chamber can be used to measure sound power levels according to ISO 3744.

Site:  Pittsburgh Research Laboratory