Driving restrictions are a common governmental strategy to reduce airborne pollution and traffic congestion in many cities of the world. Using high-frequency data on air pollution, car trips, and mass-transit systems ridership, I evaluate the effectiveness of temporary driving bans triggered by air quality warnings in Santiago, Chile. I employ a fuzzy regression discontinuity design that uses the thresholds in the air quality index used to announce these warnings as instruments for their announcement. Results show that these temporary bans reduce car trips by 6–9% during peak hours, and by 7–8% during off-peak hours. This is consistent with air pollution reductions during peak hours, and with increases in the use of Santiago's mass-transit systems during hours the systems run with excess capacity. Increments in mass-transit ridership uncover the importance of alternative modes of transportation in securing the effectiveness of temporary driving bans.

限制驾驶是减少世界上许多城市的空气污染和交通拥堵的一项政府共同战略。我使用有关空气污染，汽车旅行和公交系统乘客的高频数据，评估了智利圣地亚哥因空气质量警告而触发的临时驾驶禁令的有效性。我采用了一种模糊回归不连续性设计，该设计使用用于宣布这些警告的空气质量指数中的阈值作为其警告的手段。结果表明，这些临时禁令在高峰时段减少了6–9％的出行，在非高峰时段减少了7–8％的出行。这与减少高峰时段的空气污染，以及在运行过量的小时内使用圣地亚哥的公共交通系统相一致。