Effectiveness of in-room air filtration and dilution ventilation for tuberculosis infection control.

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. Near the emission source concentration were higher. It was found that both the air flow configuration of the filter and its placement within the room were important.