Noise level and sound insulation of industrial control rooms

Abstract

According to the standard ISO 11690-1, the maximum recommended background noise level of an industrial control room is 35-55 dB(A). In this study, the noise levels and the sound insulation performance of the control rooms were measured in situ in 16 control rooms in different industrial areas. The standard ISO 11957 was applied for the measurements. The average A-weighted sound pressure levels inside the control rooms varied between 44-62 dB(A), and outside between 65-92 dB(A). The greatest apparent sound pressure insulation of the control rooms was 45 dB. The reasons for this excellent sound insulation were the massive wall structure, the double-glazed windows with a large air space. In addition, getting from the control rooms to the hall required going through two doors. The smallest control room insulation was 18 dB. The reasons for this poor sound pressure insulation were the light wall structures, the thin double-glazed windows with a small air space and a light single door. In addition, the sound insulation spectrum was very flat implying a leaking structure. Half of the noise levels of the control rooms studied exceeded 55 dB(A), and 44% of operators considered the noise disturbing.