Study on the CO concentration upper limit in highway tunnel

In order to perfect criterion of CO concentration upper limit in the design of ventilation system for road tunnel, the influence of CO on person is analyzed, and the influence is judged by the COHb concentration made in human blood. On the basis of Coburn-Forster-Kane model, the relationship between CO concentration and COHb concentration in human blood is analyzed. Then the relationship between the time the vehicles passing through the tunnel and the CO concentration upper limit is obtained. The influence of altitude, ventilation type and traffic situation on the CO concentration upper limit is also analyzed here. Forming all these results in table, comparing with the CO concentration upper limit of criterion, it´s clear that the longer the time requires passing through the tunnel, the higher the value is in criterion. The result can be used to guide design of ventilation system for road tunnel.