Exposure to carbon monoxide during indoor karting

Karting is a recreational activity of increasing popularity and it is often practiced indoors leading to build up of toxic gases in ambient air. This study was realised to verify the level of exposure to carbon monoxide (CO) in ten male racers (Age: 15 to 49 years old) during a 45-min race. The alveolar concentration of CO (alvCO) for each participant was measured before and after the race. The ambient CO level was determined continuously from the start to the end of the race with two detectors. Mean ambient air CO concentration was 41 ppm and the average increase of alvCO for the ten subjects was 16.2 ppm corresponding to about 3% COHb. Based on these results and on the Coburn model, a reference limit of 25 ppm was suggested for a 1 h exposure during indoor karting. At the request of the public health authorities, some modifications were made to the karts, to the CO monitoring surveillance system and to the ventilation system of the building. CO concentrations were monitored thereafter. The guideline of 25 ppm for 60 min was always respected.