A PERMISSIBLE CARBON MONOXIDE CONCENTRATION LIMIT MODEL FOR LONGITUDINAL TUNNEL WITH SHAFTS

摘要

Carbon monoxide is taken as the reference pollutant for assessment of the toxicity of the exhaust gases from vehicles due to its chemical and biologic property that inhibits the blood’s capacity to carry oxygen directly by attaching itself to hemoglobin and forming a toxic compound known as carboxyhemoglobyne. And the current code Specifications for Design of Ventilation and Lighting in Highway Tunnel in China didn’t provided specific permissible CO concentration limits for longitudinal ventilation tunnels with shafts which have different CO concentration profiles compared to common longitudinal ventilation tunnels. A permissible CO concentration limit calculation model for longitudinal tunnel with shafts based on the difference form of original CFK equation (Coburn et al. 1965) is presented. And the results prove that permissible CO concentration limits for longitudinal ventilation tunnels with shafts can be set at the same level of common longitudinal ventilation tunnels.