Noise in Canadian hospital operating rooms

Noise levels in hospital operating rooms have not been well characterized. Therefore, noise levels were measured using a sound level meter in a sample of surgeries included in a multihospital intervention study, assessing the effectiveness of a recommended work practice to decrease occupational exposure to blood during surgery. The duration of the measurements ranged from 15 min to several hours. Among types of surgery for which at least four measurements were done, the Leq for orthopedic surgery was the highest at 70.1 dB(A) (range 60.8–75.1), followed by 63.7 dB(A) for neurosurgery (range 57.4–68.1), and 62.8 dB(A) (range 58.5–70.3), for general surgery. Gynecological surgery had the lowest Leq, 60.8 dB(A) (range 56.5–62.5). Peak levels were found to be as high as 132.8 and 132.6 dB(A), in general and orthopedic surgery, respectively, and lowest in neurosurgery at 102.6 dB(A). These noise levels are consistent with those from a comprehensive U.S. study, and substantially exceed EPAs recommended level of 45 dB(A) for hospitals. [Work funded by Ontarios Workplace Safety Insurance Board.]