Air velocities have been measured in the master bedroom, kitchen, and basement of six occupied homes plus the dining/living room area of one unoccupied house. Median air velocities of 5.3 and 12.4 cm/s in the occupied and unoccupied houses raise concern that inadequate air movement may sometimes exist for accurate passive monitoring of pollutant vapors. Central-air circulation systems had a variable impact on air velocity. Median velocities increased from 5.8 to 6.2, 3.2 to 5.7, 1.5 to 8.1, and 4.4 to 15.5 in three occupied and one unoccupied houses, respectively. Median velocities of 4.2, 4.3, and 10.2 cm/s in the master bedroom, basement, and kitchen, respectively, are consistent with increased occupant activities and use of ceiling and/or exhaust fans in or near the kitchen. (ERA citation 12:039571)