Noise in multiple-workstation open-plan computer rooms: measurements and annoyance.

Computers in the workplace have become very prevalent. As with the introduction of any new technology, unanticipated problems often develop. Noise in open-plan computer rooms and annoyance and perceived deterioration in performance associated with it also appears to be a problem that may be similarly categorized. An experimental investigation was undertaken as a result of frequent user complaints about the difficulty of concentrating and performing their work in the computer rooms of a large service organization. Two typical computer rooms were investigated. Noise levels were measured at random times during the working hours. The noise spectrum was found to be almost similar in both facilities. The 10-second A-weighted noise level for all frequencies ranged between 53 and 62 dB. Most noise energy was either in the high-frequency bands (above 2,000 Hz) or low-frequency bands (below 500 Hz). The highest noise energy levels were recorded at 8,000 Hz (between 64 and 73 dB). Least noise energy levels were recorded between 500 and 2,000 Hz (between 35 and 44 dB). The noise spectrum, thus, was substantially different from those of open-plan offices. Eighty-nine percent of the users questioned indicated their tasks required concentration. Fifty percent of all respondents rated the noise level between extremely annoying and unbearable and intolerable (scale values between 22 and 25 on a 25-point scale; 1 being noticeable but not objectionable and 25 being unbearable and intolerable); 10% of the respondents considered the noise very annoying; 20% of the respondents considered the noise levels moderately annoying; the remaining respondents did not seem to have a major problem. Conversational sound and computer-printer beeping sounds were reported to be most annoying by 90% of the respondents who considered the noise levels annoying. Constant arrival and departure of users, sound from keyboards, and ventilation equipment also appeared to be major contributing factors.