Room noise criteria--the S12.2-1995 standard raises serious technical and economic considerations.

Abstract

The key issue with the S12.2-1995 standard is not the differences in the assessment of sound quality, particularly at the low frequencies, but rather the use of octave-band data to describe low-frequency equipment misbehavior. Unfortunately, the "NCB vs RC" controversy leads research efforts and technical discussions in the wrong directions, disregarding serious economic and technical considerations. This conflict can be resolved by: (1) avoiding the use of octave-band data to rate noise with abnormal (spectral and/or temporal) characteristics, (2) addressing the widespread need for the room noise criteria as a practical design tool for general use in architectural spaces, and (3) developing adequate descriptor/procedures to qualify, quantify, and determine the impact of "rumble" on human response. A further goal should be to develop integrated criteria that would apply to both HVAC and computer noise sources.