pollutant

Energy saving measures with reduced outdoor air change rates may lead to critical indoor air contaminant concentrations. Emission characteristics of construction materials and products play an important role. Therefore a project has been set up at EMPA to investigate emission characteristics of such materials using test chambers.

A generalized multi-chamber ventilation model is developed for air contaminant prediction problems where the parameters of the system, such as airflow rates, are described by Gaussian probability distributions. A numerical solution, utilizing stochastic differential equations (SD E's), is provided to facilitate its application. The model is used to calculate contaminant concentration histories described by means and standard deviations. It is also used to show the sensitivity of concentrations to the variation of such parameters as infiltration flows and contaminant source rates.