Noise exposure in the orthopaedic operating theatre: a significant health hazard

BACKGROUND: Surgeons working in orthopedic operating theatres are exposed to significant noise pollution due to the use of powered instruments. This may carry a risk of noise-induced hearing loss. The present study was designed to quantify the noise exposure experienced by surgeons and establish whether this breaches occupational health guidelines for workplace noise exposure. METHODS: A sound dosimeter was worn by the operating surgeon during three total hip replacements and two total knee replacements. A timed record of the procedures was kept concurrently. Noise levels experienced during each part of the procedure and total noise exposures were measured. Noise exposures were compared with occupational health guidelines. RESULTS: Noise exposure in total hip replacement averaged 4.5% (1.52-6.45%) of the allowed daily dose (average duration 77.28 min). Total knee replacement exposure was 5.74% (4.09-7.39%) of allowed daily exposure (average duration: 69.76 min). Maximum sound levels approached but did not exceed recommended limits of 110 dBA (108.3 dBA in total hip replacement and 107.6 dBA in total knee replacement). Transient peak sound levels exceeded maximums of 140 dB on multiple occasions during surgery. CONCLUSIONS: Overall total noise dose during orthopaedic surgery was acceptable but orthopaedic surgeons experience brief periods of noise exposure in excess of legislated guidelines. This constitutes a noise hazard and carries a significant, but unquantified risk for noise-induced hearing loss.