Open‐plan offices may be hazardous to persons with impaired hearing

Abstract

The increasingly popular open‐plan design of office space defines work zones not by room partitions, but by free‐standing barriers and specially constructed acoustical environments. The key ingredient in achieving privacy, while maintaining the desired flexibility of the open‐plan office, is the insertion of low‐level masking noise throughout the space. While the level chosen for the background noise depends on several architectural and personal factors, broadband noise at levels up to 52 dBA is acceptable, at least to most people with normal hearing (ASTM, 1976). But what about the substantial segment of the population that is known to have a significant hearing problem? It is well known, for example, that a major limitation of the listener with sensorineural hearing damage is the inability to understand audible speech presented against a background of competing sound. For the impaired listener, the ratio of speech to background level (or S/N) must be increased by about 10 dB over that measured for normally hearing individuals. It thus appears that the modern design of office space, emphasizing acoustical sound insulation, is totally incompatible with the auditory abilities of many potential, especially elderly, users of these enclosures. In the present paper the limitations of the open office plan for handicapped listeners are examined; where appropriate, design criteria are recommended.