What is an acceptable noise level for a fume hood?
Most standards specify that the noise level from a fume hood, as measured 6″ in front of the hood, should be around 60 dBA (normal conversation level). This noise would be the total noise accumulated from the terminal exhaust box (device to control the airflow leaving the hood) and any operations directly from the hood (movement of sash, etc.). Another criteria used for laboratory noise levels are Noise Criteria Curves (NC-curves). NC-levels refer to the constant background noise in a total laboratory. NC levels for a lab should be below NC 50.
