Laminar air flow provides high air quality in the operating field even during real operating conditions, but personal protection seems to be necessary in operations with tissue combustion.

We measured bacterial and particle concentrations at the level of operative fields during 105 operation procedures under laminar air flow conditions. Measured concentrations were at least a factor of 20 lower than in comparable rooms without ultra-clean air and laminar air flow. Kind of operation (septic/aseptic), number of participating persons and quantity of talking seem to have less influence on air quality than presumed, single use cover improves the air quality. The number of ultra-fine and small particles was dramatically increased when tissue was coagulated during operation. This may pose health risks to surgeons and nurses, needs risk assessment and decisions about personal protection.