Calculation of natural ventilation rates by tracer gas decay method was proposed, and definition of indoor criterion of carbon monoxide concentration limit and the carbon monoxide emission from cars were discussed.

• 提出了利用示踪气体法计算地下停车库的自然通风量，并论述了如何确定室内一氧化碳允许标准及小汽车的一氧化碳排放量。