Control of wildfire-sourced PM2.5 in an office setting using a commercially available portable air cleaner

A steady increase in wildfire event severity and season length has led to greater potential for exposure to fine particulate matter associated with wildfire smoke. Research has found fine particulate matter to be correlated with a myriad of health ailments and thus effective strategies for controlling exposures are needed. In this study, a correction factor associated with wildfire-sourced fine particulate matter was established for a TSI SidePak AM520 by conducting sampling with a co-located MetOne BAM 1020. Portable air cleaner efficacy was assessed by simultaneously measuring PM_2.5 mass concentrations in two identical offices with the inclusion of a portable air cleaner in one. The relationship between indoor and outdoor PM_2.5 mass concentrations was assessed by comparing concentrations recorded in an office to those recorded at the nearest National Ambient Air Quality Standards monitoring station. Results revealed that a portable air cleaner reduced indoor fine particulate matter within an office by 73% and 92% during working and non-working hours, respectively, and that a strong significant correlation (ρ = .91, p = 0.00) existed between indoor and outdoor fine particulate matter mass concentration measurements. A direct relationship between indoor and outdoor PM_2.5 mass concentrations was observed during this study, suggesting that elevated fine particulate matter concentrations due to wildfire smoke could be a concern in the indoor work environment; however the current study determined that the use of a portable air cleaner can substantially decrease fine particulate matter concentrations even in an active office setting.