Lessons learned from a woodstove changeout on the Nez Perce Reservation.

A woodstove changeout program was conducted within 16 homes on the Nez Perce Reservation in Idaho to evaluate the effectiveness of a woodstove changeout in improving indoor air quality. PM(2.5) samples were collected within the common area (rooms where the stoves were located) of the homes both before and after the installation of cleaner burning EPA-certified stoves. During the pre- and post-changeout sampling, indoor PM(2.5) mass, Organic Carbon (OC), Elemental Carbon (EC), and chemical markers of woodsmoke (including levoglucosan) were measured. Sampling results from this study showed that indoor air quality was improved in 10 of the 16 homes following the woodstove changeout and educational training program. Five homes had increased indoor PM(2.5) concentrations following the changeout, while one home did not have final PM(2.5) results for comparison. The median pre-changeout PM(2.5) mass (as measured by TSI DustTraks) was 39.2 μg/m³, with a median post-changeout concentration of 19.0 μg/m³. This resulted in an overall 52% reduction in median indoor PM(2.5), a 36% reduction in mean indoor PM(2.5) and a 60% reduction in PM(2.5) spikes when the old stoves were replaced with EPA-certified stoves. Another significant finding of the project was that targeted education and outreach is a critical component of the overall success of the program. Effective messaging to homeowners on proper use of their new stove is a necessary task of a woodstove changeout.