Noise levels in adult and pediatric orthopedic cast clinics.

Prolonged exposure to high-intensity noise has been associated with noise-induced hearing loss, hypertension, psychological stress, and irritability. The National Institute of Occupational Safety and Health considers levels above 85 decibels (dB) as harmful. In the study reported here, we sought to determine whether noise levels in orthopedic cast clinics were within safe limits. A calibrated noise dosimeter was worn by cast technologists during 7 adult and 7 pediatric cast clinics, and noise levels were recorded. Mean equivalent continuous noise levels were 77.8 dB (adult clinics) and 76.5 dB (pediatric clinics), mean noise levels adjusted for an 8-hour day were 76.6 dB (adult) and 75.9 dB (pediatric), and mean peak noise levels were 140.0 dB (adult) and 140.7 dB (pediatric). Mean noise levels in cast clinics were within safe limits and there was no statistical difference in noise levels between adult and pediatric clinics. However, peak noise levels in all clinics exceeded recommended limits, and even brief exposure to noise of this intensity may be hazardous.