MODELING AND MONITORING OF CO, NO AND NO//2 IN A MODERN TOWNHOUSE.

Mass-balance models for indoor concentrations of CO, NO and NO//2 were applied to an energy-efficient townhouse. Model parameters included source emission rates, infiltrating airflows, and, for NO//2, loss rate coefficients. Emission factors for CO, NO and NO//2 were estimated for each of the gas-fired appliances in the house. Airflows were estimated using sulfur hexafluoride (SF//6) decay techniques. Loss rates for NO//2 were calculated as the difference between NO//2 removal rates and estimated air exchange rates; CO and NO concentrations decayed at a rate not significantly different than that for SF//6. Comparing model predictions with measured concentrations yielded differences averaging 17% for CO and NO, and 28% for NO//2.