Emission factors for domestic use of L.P. gas in the metropolitan area of Mexico City

One of the main problems found in air pollution in the Metropolitan Area of Mexico City (MAMC) is the presence of high concentrations of ozone at ground level in the atmosphere. The official Mexican standard for ozone concentration in the air (0.11 ppm, one hour, once every 3 years) has been exceeded more than 300 days per year. Ozone is formed due to the emissions of nitrogen oxides and hydrocarbons originated from either combustion processes or vapors emanating from fuel handling operations. The results of an evaluation of several domestic devices like stoves and water heaters with L.P. gas as fuel are presented. A method for the evaluation of hydrocarbon emission was developed. A prototype of domestic installation was constructed. The prototype includes L.P. gas tank, domestic stove, water heater, piping and instrumentation. Several combinations of stoves and water heaters were evaluated. The sampling and analysis of hydrocarbons were performed using laboratory equipment originally designed for the evaluation of combustion and evaporative emissions in automobiles: a SHED camera (sealed room equipped with an hydrocarbon analyzer) was used to measure leaks in the prototype of domestic installation and a Constant Volume Sampler (CVS) for the measurement of incomplete combustion emissions. Emission factors were developed for each domestic installation