Validation of the indoor exposure model for dwelling life cycle assessment

Damage to human health as a result of exposure to contaminants emitted to indoor air is poorly addressed in life cycle assessment tools for dwellings. A new model is available to calculate damages to human health caused by contaminants emitted from building materials, using a multizone indoor airflow and exposure model. Ventilation rates and radon concentrations have been simulated for the Dutch reference dwelling and are compared with measurement data from the Dutch Ecobuild houses and from average ventilation rates and radon concentrations in dwellings in the Netherlands. The ventilation rates and radon concentrations as simulated with the indoor exposure model have the same order of magnitude as the ventilation rates and radon concentrations measured in the Ecobuild dwellings and in both radon surveys, except for the crawl space, where the modelled ventilation rates are overestimated and the radon concentrations are underestimated. Overall, the indoor airflow and exposure model gives a good reflection of actual ventilation rates and radon concentrations, but for the crawl space, the model needs to be adjusted, and the effects of mechanical ventilation on the model results need to be tuned to practice.