Clean air in the operating room is important during joint replacement surgery. We compared monochromatic ultraviolet radiation of254 nm with the use ofa Charnley-Howorth air enclosure by bacterial air-sampling during 113 total hip arthroplasties. Air samples were taken continuously at the edge of the wound and every 15 minutes at a site 130 cm from the operating table. We also tested the effect of occlusive clothing for all personnel.

We have evaluated the effect of shortwave ultraviolet radiation on bacterial levels in an operating theatre, both in experimental conditions and during 20 hip operations. When compared with the use of sham blue light, there was a significant reduction in the number of bacteria. The reduced level was comparable with that suggested for ulfraclean air ventilation systems.