Impact of Do-It-Yourself and Commercial Air Cleaner Usage on Health and Residential PM2.5

Abstract

Background and aim: Wildfire smoke can threaten health, necessitating creating cleaner indoor air spaces. Commercially available portable air cleaners (PACs) mitigate smoke impacts indoors but can be expensive or inaccessible. Lower-cost Do-It-Yourself (DIY) PACs (furnace filter attached to box fan) offer an affordable alternative. However, evidence of their effectiveness in real-world settings is limited. This pilot study aimed to 1) evaluate the effect of DIY/commercial PAC usage on indoor PM2.5 and health outcomes during wildfire season among tribal community members in Hoopa, California and 2) assess barriers and facilitators to use of either intervention. Methods: During four one-to-two-week phases (baseline; DIY PAC usage ≥8 hours/day; commercial PAC usage ≥8 hours/day; and air sensor with visual display with optional PAC use), we monitored indoor and outdoor PM2.5 at participants’ homes. We conducted phase-specific phone surveys about participants’ health, behaviors, and perceptions. We analyzed indoor PM2.5 and health outcomes associated with PAC usage using mixed effects multivariate linear regression and tabulated behavioral responses. Results: DIY and commercial PAC usage was significantly associated with reduced infiltrated PM2.5 (n=6). High usage (≥30% of phase) of either PAC was significantly associated with improved health (measured as a composite score), relative to low usage (<10% of phase) (n=10). Noise was the primary barrier to DIY PAC use, while quiet operation and small size of commercial PACs facilitated use. Nonetheless, eight of nine participants who preferred commercial PACs said they would use DIY PACs if the air were very smoky. Conclusions: DIY and commercial PACs were associated with improved indoor PM2.5 and health, but the loudness of DIY PACs hindered use. State, local, and tribal organizations should consider these conclusions in tailoring messaging and allocating resources in preparation for wildfire seasons. Disclaimer: Does not reflect EPA views or policy. Keywords: Indigenous, wildfire smoke, indoor air quality