In the light of EEC proposals on the avoidance of damage to hearing caused by noise, a study was undertaken to determine the risk posed by powered orthopaedic instruments. The noise levels from a number of air-powered and electric tools were measured and analysed and found to exceed the recommended levels. The predicted daily personal noise exposure was calculated and the potential for hearing damage confirmed. Twenty-seven senior orthopaedic staff were then assessed by audiometry; evidence of noise-induced hearing loss was found in half the subjects. The increasing use of powered instruments in elective orthopaedics and fracture fixation may present a significant cumulative risk to the hearing of orthopaedic surgeons and theatre personnel. The use of ear defenders should be promoted, and manufacturers should be encouraged to develop instruments with lower noise emission levels.