The effectiveness of in-room air filtration systems was experimentally evaluated, specifically portable air filters (PAFs) and ceiling-mounted air filters, in conjunction with dilution ventilation, in order to control TB exposure in high-risk environments. A test aerosol was continuously generated and released into a full-sized room. Time-averaged airborne particle concentrations were measured at several points. The effectiveness was determined by a comparison of particle concentrations with and without device operation. Increasing rate of air flow did not always increase effectiveness.
The energy saving practice of stopping ventilation systems at night may reduce the daytimeair quality. Sorption phenomena where pollutants absorbed at night are reemitted during theday and the general slower removal of pollutants at the reduced average ventilation rates willcontribute to the deterioration of air quality at intermittent running systems. The purpose ofthe study was to investigate the impact on construction product emission during the day fromreduced ventilation rates at night. Experiments were performed in three small-scale chambersof Climpaq type with dilution systems.