Prevention against carbon monoxide poisoning emanating from burning coal briquettes – Generation rate of carbon monoxide and ventilation requirement –

Carbon monoxide (CO) poisoning accidents occur every year in Japan, most of which are caused by the incomplete combustion of fuel, such as gasoline, light oil, and coal briquettes. To prevent CO poisoning in workers, it is essential to reduce the CO concentration in a working environment below the criteria threshold through ventilation. Although proper ventilation requirements for enclosed spaces are estimated from the generation rate of air pollutants, there is no empirical research evaluating the CO generation rate of coal briquettes. In this study, the author evaluated the CO generation rate of burning coal briquettes under controlled laboratory conditions and estimated the appropriate corresponding ventilation requirements. Despite the coal briquettes were burned under sufficient oxygen supply, the CO generation rates and the briquettes’ consumption rates were 146–316 mL/min/kW and 1.65–3.61 g/min, respectively. Assuming the CO concentration limit was 50 ppm, the corresponding ventilation requirement was 174.9–378.7 m(3)/h/kW. The ventilation requirement was 43.7–94.7 m(3)/h/kW when the critical CO concentration was set at 200 ppm. Adopting the ventilation requirements set out in this study could facilitate proper ventilation and reduce the risk of CO poisoning.