CHOICE OF VENTILATION SYSTEM FOR OPERATING-THEATRES: Comparison of Turbulent versus Laminar/Linear Flow Systems in Operating-rooms and Industrial Clean Rooms

Abstract

General air counts and critical worksite counts of bacteria and particles greater than 0·5 μ in diameter done in operating-rooms ventilated by turbulent flow have been compared with those for industrial clean rooms where the ventilation flow was turbulent or of horizontal or vertical laminar/ linear type. The industrial clean room with turbulent-flow ventilation was more crowded and had a higher staff activity than the most active operating-room, yet both particle and bacterial counts were lower than in the least-contaminated operating-room. Bacterial and particle counts were lower still in the industrial clean rooms using laminar/linear flow both for the general air and for critical work sites, and the improvement was more striking for the room with vertical laminar/ linear flow. Thus experience in an industrial clean room used for computer assembly supports the choice of vertical laminar/linear flow as the ventilation system for operating-theatres.