Changing levels of quiet in an intensive care nursery

Abstract

Objectives: To document low sound levels, the range and pattern of levels, and the relative effects of operational (staff and equipment generated) and facility (building generated) noise on the acoustic environment of a level III nursery. Study Design: A quasi-experimental, prospective, longitudinal study of one bed space. Operational noise was reduced through staff behavior change while facility noise was reduced through renovation. Results: Initial noise levels were typical of those in the literature and in recently measured nurseries. About 80% of sound levels were between 62 and 70 dBA. The lowest levels (Lmin) were 60 to 65 dBA. After staff behavior change, Lmin was about 56 dBA although the highest levels (Lmax) remained at 78 to 100 dBA. Levels following renovation were reduced to Lmins of 47 to 51 dBA and Lmaxs of 68 to 84 dBA, perceived as three or four times quieter than initially. Conclusions: Staff behavior as well as the acoustical characteristics of the facility determine the levels of noise and quiet in an intensive care nursery.