Traviss Nora, Allen George, Ahmadi Mahdi
Northeast States Coordinated Air Use Management (NESCAUM), Boston, Massachusetts 02111, United States.
Keene State College, Keene, New Hampshire 03435, United States.
ACS EST Air. 2024 Aug 12;1(9):1190-1202. doi: 10.1021/acsestair.4c00135. eCollection 2024 Sep 13.
Air pollution from residential wood heating (RWH) presents challenges at the intersection of climate and public health. With a revised National Ambient Air Quality Standard (NAAQS, at 9 μg/m) for particulate matter (PM) in the United States (U.S.), the Environmental Protection Agency (EPA) will likely classify new non-attainment areas due primarily to emissions from RWH. Agencies will use emissions factors (EFs) to develop attainment strategies. Many will rely on EPA modeling platforms based on data from the National Emissions Inventory (NEI). The NEI uses RWH EFs based on data from mid-1990's in-situ studies and a speciation profile from a 2001 study of fireplace emissions. The NEI does not include greenhouse gas (GHG) emissions for this sector, which plays a key role when assessing climate reduction strategies for the buildings sector. Here, we tested seven wood stoves to determine EFs, representing various vintages and control technologies, using a novel test method that reflects in-use operational settings called the Integrated Duty Cycle. The study measured multiple pollutants concurrently: criteria pollutants (particulate matter [PM], CO, and NOx), nonmethane total hydrocarbons (NMTHCs), GHGs, black carbon (eBC), brown carbon (BrC), and multiple hazardous air pollutants (HAPs). We found no significant difference in PM EFs between uncertified and non-catalytic stove technologies. RWH EF results from this study exceeded 2020 NEI RWH EFs for NMTHC and multiple HAPs. Applying our study's EFs to the 2020 NEI suggests that RWH, compared to all other sources, ranks as the 2nd largest source category of formaldehyde; the 3rd largest of benzene, 1,3-butadiene, and acrolein; and the 4th largest of Pb emissions. RWH also emits more methane compared to natural gas or oil residential heating, raising questions about substitution of wood as a climate neutral heating fuel. However, compared to uncertified stoves, pellet stove EFs (except toxic metals) were significantly lower ( < 0.01). In summary, RWH appears to be an underestimated source of PM (non-catalytic technology), methane, NMTHC, toxic metals, and other HAPs, which has important implications for climate and public health policy in the U.S. and globally.
住宅木材取暖（RWH）造成的空气污染在气候与公共卫生的交叉领域带来了挑战。随着美国对颗粒物（PM）的国家环境空气质量标准（NAAQS，9微克/立方米）进行修订，美国环境保护局（EPA）可能会将主要因住宅木材取暖排放而导致的新的未达标地区进行分类。各机构将使用排放因子（EFs）来制定达标策略。许多机构将依赖基于国家排放清单（NEI）数据的EPA建模平台。NEI使用的住宅木材取暖排放因子是基于20世纪90年代中期的实地研究数据以及2001年一项壁炉排放研究的物种分布情况。NEI未包括该部门的温室气体（GHG）排放，而这在评估建筑部门的气候减排策略时起着关键作用。在此，我们测试了七台木炉以确定排放因子，这些木炉代表了不同年份和控制技术，采用了一种反映实际使用操作环境的新颖测试方法，即综合 duty cycle。该研究同时测量了多种污染物：标准污染物（颗粒物[PM]、一氧化碳和氮氧化物）、非甲烷总烃（NMTHCs）、温室气体、黑碳（eBC）、棕碳（BrC）以及多种有害空气污染物（HAPs）。我们发现未经认证的炉灶技术和非催化炉灶技术在颗粒物排放因子方面没有显著差异。本研究得出的住宅木材取暖排放因子结果在非甲烷总烃和多种有害空气污染物方面超过了2020年NEI中的住宅木材取暖排放因子。将我们研究的排放因子应用于2020年NEI表明，与所有其他来源相比，住宅木材取暖是甲醛的第二大来源类别；是苯、1,3 - 丁二烯和丙烯醛的第三大来源；是铅排放的第四大来源。与天然气或石油住宅取暖相比，住宅木材取暖还排放更多甲烷，这引发了关于用木材替代作为气候中和取暖燃料的疑问。然而，与未经认证的炉灶相比，颗粒炉的排放因子（有毒金属除外）显著更低（<0.01）。总之，住宅木材取暖似乎是颗粒物（非催化技术）、甲烷、非甲烷总烃、有毒金属和其他有害空气污染物的一个被低估的来源，这对美国乃至全球的气候和公共卫生政策都具有重要意义。
