This report investigated the association of occupational exposure to nitrogen oxides with respiratory infections in British coal miners. Dr. Jacobsen and colleagues leveraged data from the Pneumoconiosis Field Research Study, a long-term epidemiological study of British coal miners with information for the years 1953-1978. A retrospective nitrogen oxide exposure assessment was conducted using records on work attendance, occupational history, mining practices, and mine conditions to construct a linear regression model of exposure with estimate errors derived from direct shift-average measurements. Health outcomes were taken from repeated medical surveys and sickness absence records. The exposure and health data were analyzed for associations between exposure to nitrogen oxides and risk of respiratory infection; the relative risk of infections at various levels of exposure was reported.