Ozone decay rates in residential garages

In this study, ozone decay rates were determined for twelve residential garages with a range of sizes, level of attachment to the occupied space, and clutter. Air exchange rates for garages were measured to have a mean of 0.47 (±0.18) hr−1. The mean ozone decay rate in these garages was 2.7 (±1.1) hr−1, a value comparable to previous data for occupied space ozone decay rates. There were differences in ozone decay rates between one-car and two-car garages, which seemed to be correlated with the volume/area ratio. Using these and previously published data, it was concluded that, under normal conditions, ozone penetration through garages to the occupied space is not a significant pathway. However, there are some conditions for which garages may be a major pathway for ozone entry into homes. One example of this is when both the garage door and the door connecting the garage to the occupied space is opened for a long period of time.