This paper finds that a 10 μg/m3 increase in airborne particulate matter (PM10) reduces life expectancy by o.64 years (95% CI: 0.21, 1.07). This estimate is derived from quasi-experimental variation in PM10 generated by China's Huai River Policy, which provides free or heavily subsidized coal for indoor heating during the winter to cities north of the Huai River but not to the south. The findings are derived from a regression discontinuity design based on distance from the Huai River, and are robust to using parametric and non-parametric estimation methods, different kernel types and bandwidth sizes, and adjustment for a rich set of demographic and behavorial covariates. Furthermore, the shorter lifespans are almost entirely due to elevated rates of cardiorespiratory mortality, suggesting that PM10 is the casual factor. The estimates imply that bringing all of China into compliance with its Class I standards for PM would save 3.7 billion life years.