The effect of ventilation rate and filter performance on indoor particle concentration and fan power consumption in a residential housing unit

This paper reports a study of the effect of ventilation rate and filters performance on indoor particle concentration and fan power consumption in a residential housing unit with a mechanical ventilation system. Through an adapted mass-balance model, indoor particle concentrations were calculated for various ventilation rates, filter performances and room sizes. Additionally, the influence of air-exchange effectiveness and cross-contamination around the exterior air vent on the indoor particle concentration was considered. Recirculation of indoor air was not considered. From the results, filters for which the performance was lower than MERV07 were found to be insufficient for reducing indoor particle concentrations below the levels obtained under no ventilation. A higher ventilation rate was needed for the given amount of indoor particle sources for a smaller size residential housing unit in comparison to the larger units. The minimum ventilation rate was less sensitive to variations in the air-exchange effectiveness inside the residential housing unit and the cross-contamination index around the exterior air vents. To satisfy the ventilation requirement for gaseous pollutants and keep the particle concentrations below those under no ventilation, a filter with a performance that would exceed MERV11 should be used when the size of the residential housing unit is in the range of 150-300 m³.