A large number of toxic gases such as carbon monoxide (CO) and nitrogen oxides (NOx) are produced from the blast models during the drill and blast tunneling excavation. However, the emission characteristics of blast design models have never been mentioned in previously published studies. To acquire the cleanest blast model and reduce environmental pollution, this paper for the first time compares the emission characteristics of CO and NOx from three traditional blast design models, i.e., NTNU, Swedish, and China models, which is the most used in tunneling. Firstly, the detailed blasting parameters of three models are put forward based on one certain 42.3m² cross-section tunnel. After that, the emission characteristics of each model is evaluated based on the indexes of total emission, emissions per area, and emission increment. Meanwhile, the tunnel face of the models is divided into four functional sections, i.e. cut zone, stoping zone, lifter zone, and contour zone to explore the influence of functional blastholes on gas emissions. Finally, these results indicate that the CO and NOx emissions of the China model are the least, followed by Swedish and NTNU models. And the total emissions are dominated by the stoping blastholes. Therefore, it is effective to reduce environmental pollution by adjusting the parameters of the stoping zone. This research can provide a reference for the tunnel engineers to design blast models to reduce environmental pollution.