高原地区由于海拔高度的增大，空气性质及部分有害气体毒性较平原地区发生了较大变化，施工通风难度比常压下增大很多，不能以平原地区的通风技术进行简单照搬。对海拔高度与空气性质的关系，高原隧道施工通风需风量计算，高原地区通〖JP2〗风阻力变化及风机选型进行了分析。结果表明，高原地区的施工通风风量计算应考虑不同海拔高度时有害气体的体积膨胀及浓度限值，进行风机选型与通风阻力计算时应根据高原空气密度与平原地区空气密度的比值进行修正，该结论可为高原隧道施工提供借鉴和参考。

The air quality and the toxicity of some harmful gases in plateau area are different from those in plain area. Therefore, the tunneling ventilation in plateau area is more difficult than that in plain area. The correlation between the altitude and the air quality, the calculation of the air volume needed in tunneling ventilation in plateau area, the variation in the ventilation resistance in plateau area and the fan selection in plateau area are analyzed. The study shows that the volumetric expansion and concentration limit of harmful gases at different altitudes should be considered in the calculation of the air volume needed in tunneling ventilation in plateau area and that modification should be made on the fan selection and the ventilation resistance calculation according to the ratio between the air density in plateau area and that in plain area. The paper can provide reference for tunneling in plateau area.