The use of HEPA filters may help to mitigate cardiovascular risks factors caused by combustion-derived air pollution (CDAP), (specifically woodstove and traffic emissions). We hypothesize that HEPA filter use and improved woodstove technology will help decrease indoor occurrences of CDAP. This project will help address knowledge gaps in CDAP-related health risks and benefits of interventions. Specific objectives include establishing a relationship between exposure to CDAP and biomarkers of cardiovascular risk and evaluating the impact of HEPA filter use towards improved indoor air quality and health indicators.