1. 1

2. 2

3. 3 Presentation Safety Health impacts Carbon monoxide Particulate Matter (PM) Wood stoves

4. 4 Safety Perform regular maintenance Avoid installing unvented (or "vent-free”) heating appliances Consider using only sealed-combustion, induced draft, or power-vented furnaces, boilers, and water heaters For gas range, use properly sized range hood fan After installation of combustion and/or ventilation equipment, test for proper functioning Vent clothes dryers to outside Install a carbon monoxide alarm (state law)

5. 5 Silent Killer: Carbon Monoxide (CO) Carbon monoxide (CO) is produced during any combustion You CAN’T See it Smell it, or Taste it… CO increases if combustion is deprived of O2

6. 6 Combustion-Appliance Backdrafting Depressurization Exhaust vents Wind Pulls air back down chimney or flue www.epa.gov/iaq/homes/h ip-backdrafting.html

7. 7 CO Levels (General Guidelines) 0-9 ppm No significant health risk 35-50 ppm Exposure – chronic: headaches, nausea, tired Most Detectors Start Alarming 50-70 ppm Exposure - 2-3 hours: flu-like symptoms, headache, nausea 70-200 ppm Exposure - 1 hour: dizziness, fatigue, vomiting 200-800 ppm Exposure – Minutes: unconsciousness, brain damage, DEATH

8. 8 How CO attacks…  Red blood cells prefer CO to oxygen  If enough CO in air, CO replaces oxygen in blood  Blocks oxygen from getting into body, damaging tissues and potentially causing death

9. 9 Common Sources of CO Blocked flue, chimney, vent pipes Rusted/cracked furnace heat exchanger Idling engine in attached garage Back-drafting, spillage Mal-adjusted fuel-fired space heater Unvented use of BBQ/charcoal indoors Gas stoves and ranges, water heaters Outdoor combustion exhaust near door/vent/window

10. 10 Particulate Matter (PM) Eye, nose, throat, lung irritation Bronchitis, allergies, asthma, respiratory and ear infections, cardiovascular conditions… Sooting from appliances Ghosting on walls/ceiling What is adhered-to particle?

11. 11 Wood Stoves are a Source of PM Wood stove changeouts (ambient and indoor) Filtration units (indoor) Best-burn practices (ambient and indoor). Wood banks (ambient)

12. 12 Temperature Inversions Valley Locations

13. 13 Wood Stoves

14. 14 Wood Stoves (cont.) In rural Northern Rocky Mountains of western MT, PM 2.5 is major ambient air pollution issue (especially during winter Majority of wintertime PM 2.5 comes from wood stoves (56 – 77%) Ward T, Lange T. The impact of wood smoke on ambient PM2.5 in northern Rocky Mountain valley communities. Environ Pollut. 2010 Mar;158(3):723-9. Wood-smoke can also be a local problem anywhere

15. 15 So, what can be done? Wood stove changeouts have become a common tool targeting ambient wood smoke PM 2.5 A good example is Libby, MT

16. 16 Wood Stove Changeout Old stove 40-60 g smoke/hr EPA-certified stove 2-5 g smoke/hr

17. 17

18. 18 Key Finding - Libby A major woodstove change-out can be effective in reducing ambient levels of PM 2.5

19. 19

20. 20 Exposure Assessment within Homes

21. 21 Wood Stoves

22. 22 How does a wood stove changeout impact indoor air quality? Old stove 40-60 g smoke/hr EPA-certified stove 2-5 g smoke/hr

23. 23 2006/2007 Libby Residential PM 2.5 Sampling Program Sampling focused on 20 homes containing wood stoves 24-hour PM 2.5 sampling Pre-changeout period (Oct/Nov 2006) Post-changeout (Dec 2006 – Feb 2007) Goal of program: evaluate impact of this “intervention” on indoor air quality within home

24. 24 Libby PM 2.5 Mass Results: Pre- and Post-Changeout Pre-changeout avg PM 2.5 : 53.4 μg/m 3 Post-changeout avg PM 2.5 : 15.0 μg/m 3

25. 25 Results of Multi-Winter Residential Study Overall reductions following the wood stove changeout observed in 16 of 21 homes

26. 26

27. 27 Nez Perce Wood Stove Changeout Conducted during winters of 2006/2007, 2007/2008, and 2008/2009 Kamiah and Lapwai, Idaho, on Nez Perce Reservation 16 homes

28. 28 Nez Perce Wood Stove Changeout PM 2.5 Mass Results Pre-changeout avg PM 2.5 : 43.1 μg/m 3 Post-changeout avg PM 2.5 : 126.0 μg/m 3 ~278% PM 2.5 increase

29. 29 Nez Perce Wood Stove Changeout PM 2.5 Mass Results (cont.) Pre-changeout avg PM 2.5 : 43.1 μg/m 3 Post-changeout avg PM 2.5 : 126.0 μg/m 3 ~278% PM 2.5 increase

30. 30 Importance of Training PM 2.5 Mass (µg/m 3 ) Measured in Homes Following Outreach/Education. Ward, T.J., Boulafentis, J., Simpson, J., Hester, C., Moliga, T., Warden, K., and Noonan, C.W., 2011. Results of the Nez Perce woodstove changeout program, Science of the Total Environment, 409, 664-670.

31. 31 Wood Stove Changeouts Effective in reducing ambient PM 2.5 Expensive (~$1500 - $4500) Learning curve for occupants Results can be variable for indoor air

32. 32 Filtration Units True HEPA Filters 99.97% Removal

33. 33 Randomized Trial for Indoor Smoke (ARTIS) 5-year, NIEHS-funded study Primary aim of study: assess impact on quality of life among asthmatic children following interventions that reduce in-home wood smoke PM exposures

34. 34 Preliminary Results of ARTIS Interventions 59% Reduction

35. 35 Use of Best-Burn Practices Education coupled with use of inexpensive tools Burn at proper temperatures (thermometer) 270-460 °F is optimal

36. 36 Use of Best-Burn Practices (cont.) Burn dry, seasoned wood (moisture meter) <20% moisture is optimal

37. 37 Use of Best-Burn Practices (cont.) Don’t burn trash, etc. Stove maintenance (ash cleaning, clean out chimneys, etc.) EPA Burn Wise Program http://www.epa.gov/burnwise/

38. 38 Summary – Changeouts Wood stoves are a significant source of PM 2.5 in both ambient and indoor environments Wood stove changeouts can be effective in reducing ambient wintertime PM 2.5 – results are more variable indoors Changeouts are expensive Training and education on new stoves essential

39. 39 Summary – Filtration Units Filtration units are consistently effective in improving indoor air in homes with wood stoves Improves indoor air quality by ~60%, but does nothing for outdoors Electricity costs are a concern and units can be noisy Require regular filter change-outs

40. 40 Summary – Burning Practices Best-burn practices are inexpensive and sustainable strategies Education, outreach, and training are critical

41. 41 Summary – Other Considerations Each intervention should be culturally and regionally appropriate Interventions need to be sustainable