Urban Exposure to Carbon Monoxide

Abstract

Some 500 “grab” samples of air were collected during normal urban life and analyzed for carbon monoxide (CO). Concentrations were correlated with sunshine, rainfall, wind speed, and traffic density using nonparametric and multiple-regression techniques. Local traffic density (td) accounts for 63% of the variance; equations based on td describe the CO exposure (log [χ + 1] ppm) encountered by pedestrians (0.59 + 0.133 td) and car drivers (0.92 + 0.086 td). Attenuation away from busy streets is rapid. In downtown offices, concentrations follow the general atmospheric pattern. Smoking can bring indoor concentrations above permitted 24-hour levels.