Friday, March 31, 2023

Reflections on the EPA Inspector General’s residential wood heat report

    The Environmental Protection Agency’s (EPA’s) internal watchdog, the Office of Inspector General (OIG) concluded that the agency does not have an effective program to test and certify wood stoves.  Much of the OIG's report tracks findings and positions of an earlier report by North East States for Coordinated Air Use Management (NESCAUM), which triggered the OIG report (NESCAUM 2021). But the OIG report has a level of authority over the agency and provides a roadmap for much needed changes.

    The OIG report finds extensive faults with the Office of Air and Radiation (OAR) and Office of Enforcement and Compliance Assurance (OECA) instead of laying blame with EPA leadership which for decades under both parties has failed to provide those offices with the resources and expertise they need to effectively do their job. Successive administrations have undervalued the vital role that wood and pellet stoves play, particularly for the rural poor, and also underappreciated the enormous levels of PM2.5 created by wood stoves. The United States has also failed to develop policies and invest in research and development (R&D) in this renewable energy technology that could be far cleaner.  

    The OIG did not break much new ground and wood heating insiders will not find much new.  Unfortunately, the OIG report also missed some of the same perspectives that NESCAUM missed, providing a one-sided view of many problems. Overall, the Alliance for Green Heat (AGH) agrees with most of the findings and the recommendations but is very concerned that the OIG, like the offices within the EPA that it criticized, may not have had the expertise to understand broader issues, other than ones raised by NESCAUM.  

    Both the NESCAUM and the OIG report consistently and incorrectly referred to “wood heaters” when they should have used the term “wood stoves.” Wood heaters include pellet stoves, a mainstream stove technology used by hundreds of thousands of consumers which do not share most of the problems wood stoves have and are a good alternative to wood stoves. The OIG failed to reassure consumers that pellet stoves can offer a cleaner and more trustworthy option. 

    Like the NESCAUM report, the OIG also failed to consider that the original test methods dating from 1988 may also be flawed and may not produce stoves that meet the PM2.5 emission standards.  We suspect that independent retesting of stoves using both test methods – Method 28  and ASTM E3053 - would find stoves emitting far more than the allowable emission levels.  

    The OIG’s quotable finding that consumers can still purchase stoves that failed EPA tests may gain far more traction with the media and environmental groups than it deserves. There is little evidence that those particular stove models are more susceptible to higher emissions than other models. Moreover, the dryness of the wood put into a stove and the amount of air the consumer gives the stove have an exponentially greater impact on emissions than which test method was used to certify the stove.  

    We do not agree with the assessment that EPA's funding for change-out programs should be questioned based on the NESCAUM or the OIG report. The managers of many of these change-out programs likely have far more expertise than the authors of the OIG and know all too well that changing out an old wood stove for a new one has limitations.  Many funds also go to bounty programs, education, pellet stoves, hybrid stoves and increasingly to heat pumps, not just new non-cat wood stoves.

    To get a broader perspective on these issues, we highly recommend reading an article about the experience of one manufacturer and their experience dealing with the EPA certification process as it rushed to respond and fix its system.

    Like the NESCAUM report, the OIG report did not consider the obvious option for the EPA to amend and improve E305, rather than revoking it. Neither report assessed the bigger picture of how ASTM E3053 could have been part of the effort to develop a federal cordwood test method by halting its use for 6 – 12 months, amending it and then gathering more data from it during certification testing. As a result, we have lost many years of manufacturers redesigning stoves that can better burn cordwood, instead of continuing to build stoves that burn cribs.

    Both reports are a badly needed wake-up call for the EPA which has neglected a program that deserved far more funding for decades, and our air quality has paid a price. As fossil fuel prices climb, wood heaters are getting more popular and sales have increased dramatically in recent years. Many policies and strategies are needed to reform and guide this renewable energy pathway beyond the deficiencies of the EPA’s certification program. It’s important for all stakeholders to look at the bigger picture and not be constricted by the narrative that emerged from the NESCAUM report.

    One line in the OIG report elicited ridicule from the wood heating community.  It said, “regulators and the public do not have reasonable assurance that certified wood heaters meet emission standards under real-world conditions,” (OIG 2023, 19). We can only assume that the authors of the OIG report knew that EPA emission standards were never meant to mimic real-world conditions and regulators know that all too well. For many in the wood stove industry, this statement undercut the credibility of the report.

    One weakness in the OIG report is its perfunctory treatment of the connection between Wood Smoke and Environmental Justice (EJ). The OIG did not refer to the findings in the 2015 New Source Performance Standards (NSPS), that “risks due to residential wood smoke emissions for disadvantaged population groups generally are lower than the risks for the general population due to residential wood smoke emissions,” (EPA 2010, 9). The 2015 NSPS predated the level of attention that the EPA is now supposed to give to EJ issues, but still EPA has never treated wood smoke as a serious EJ issue. The EPA relied on a very narrow 2010 study commissioned by the EPA’s Gil Wood that did not find increased cancer rate in census data that tracks with higher rates of wood smoke. A finding that wood smoke did disproportionately impact disadvantaged groups would have triggered a requirement that the EPA would have to spend resources to further study this issue. The NSPS discussed the potential causal relationship between wood smoke and cancer numerous times, but when it came to disadvantaged groups, the 2015 NSPS said:

“This proposed rule [2015 NSPS] is not subject to Executive Order 13045 (62 FR 19885, April

23, 1997) because the agency does not believe the environmental health risks or safety risks addressed by this action present a disproportionate risk to children. The report, “Analysis of Exposure to Residential Wood Combustion Emissions for Different Socio-Economic Groups,” shows that on a nationwide basis, cancer risks due to residential wood smoke emissions among disadvantaged population groups generally are lower than the risks for the general population due to residential wood smoke emissions,” (NSPS 2015, 13700). 

    AGH believes this statement is not sufficiently supported by data and reflects the interests of an NSPS process that lacked the funding and leadership to address the EJ issues that wood smoke presents for rural impoverished and marginalized communities. The OIG report did little to change this trajectory. AGH, tribes and firewood banks are urging the EPA to use EJ funds to help wood heating communities.

AGH perspectives on some of the findings of the OIG report.  Sentences in quotes are from the OIG report, followed by AGH’s commentary.

“The EPA Does Not Have an Effective Program for Testing and Certifying Wood Heaters,” (OIG 2023, 13).   

    AGH largely agrees with this basic conclusion that underlies the OIG report. Despite all the shortcomings of the EPA, which were only made widely public by NESCAUM and the Alaska Department of Environmental Conservation (ADEC), it's important to also remember that the EPA program is likely the best certification and testing program in the world for cord wood stoves, and it has pushed manufacturers to build stoves that are cleaner than anywhere else in the world. Testing of solid fuel heaters is inherently extremely complex, rendering programs to regulate them vulnerable.  

“The 2015 NSPS and Certification Test Methods Are Flawed,” (OIG 2023, 13). 

    AGH agrees that the 2015 NSPS is flawed but we should not forget some of its most important and most successful results. It finally made outdoor boilers a fully regulated appliance, and ended the loophole of allowing many wood and pellet stoves to be “exempt.” It also jump started a new category of stoves: hybrid stoves that use both catalytic and non-catalytic smoke reduction technologies. However, the operational benefits of hybrid stoves have been overlooked by ADEC and NESCAUM, contributing to California Air Resources Board (CARB) focusing on catalytic stoves in their change-out programs instead of hybrid stoves, which continue to reduce PM even if the cat is not engaged or its clogged or missing.  OECA has also made many improvements to its database of certified wood heaters. The database used to be maintained on excel spreadsheets and lacked much of the detail that it now has. We hope it will be further populated with relevant info, including the expiration date of each stove’s certificate in ways that will not confuse consumers. The EPA program is effective and credible in many ways, despite the deep flaws identified in the OIG’s report. 

  • The 1988 NSPS was far more flawed than the 2015 NSPS and for 20 years the EPA largely ignored those flaws, as did state agencies.  

  • ALT-125 and ALT-127 (ASTM E3053) could have been improved, instead of revoked.  

  • “Testing labs can conduct test runs to produce data that misrepresent wood heater performance to regulators and consumers,” (OIG 2023, 14). This has always been the case and is not a product of the 2015 NSPS.

“The Wood Heater Certificate-of-Compliance Process Lacks Internal Controls,”(OIG 2023, 19). 

    AGH agrees with this conclusion and OECA’s estimate of $100,000 to continue detailed review of certification papers is a small sum given the improvements needed. We question whether the use of contractors is the best way forward for OECA, rather than building its own internal capacity and expertise.   

  • “The Agency Does Not Exercise Its Authority to Observe Certification Testing,” (OIG 2023, 21). This activity is yet another victim of underfunding. We believe both OECA and the Office of Air Quality Planning and Standards (OAQPS) staff should regularly observe certification testing as a primary strategy to build its expertise. 

  • “The EPA Does Not Use Its Regulatory Authority to Conduct Compliance Audit Tests,” (OIG 2023, 21). We urge the EPA to begin compliance audit testing, primarily of the most popular models to start with


  • “Develop and implement a plan to demonstrate whether residential wood heaters certified using the test methods based on ASTM E3053 comply with the New Source Performance Standards for residential wood heaters,” (OIG 2023, 26). This is a nonsensical recommendation unless similar tests are done on stoves tested with Method 28. The EPA should approach all test methods without bias and develop scientific ways to assess all test methods.  

  • “Develop and adopt an EPA cord wood test method that is supported by data to provide the public reasonable assurance that certified appliances meet emission standards,” (OIG 2023, 26). Emission numbers in labs will never be the same as emissions in the hands of consumers, particularly if manually operated stoves continue as the dominant technology in North America.  Automated stoves and controls like ESPs are likely the leading options to reduce the gap between lab and field emission profiles. 

  • “Establish mechanisms to promote independence between emissions testing labs and third-party certifiers,” (OIG 2023, 26). AGH is not convinced that the next NSPS should extend the role of third-party certifiers. While it may have been a good idea, it didn’t work and other strategies should be considered before trying to fix this process.

Response of the EPA

    We believe that it's important to also read the response by the EPA to the OIG which was included in the end of the report.  We felt their response was fair and measured, and acknowledged many of the charges in the OIG report. However, the EPA also pushed back in many areas, such as this: “The OIG draft report improperly conveys that EPA has generally not altered how we are implementing the wood heater program,”(OIG 2023, 30). We fully agree with this statement because the EPA began improving their program even before the NESCAUM report came out, and accelerated their pace afterwards.  


    AGH believes the work of ADEC, NESCAUM and the EPA’s OIG is generally having a positive impact.  While there have been many missteps and miscommunication, and sometimes an inordinate burden on manufacturers, this process finally got the attention of the EPA leadership and more resources to the EPA offices working on these important issues. It is still unclear if the EPA leadership will continue to give more priority and more resources to this area in coming years and under different administrations.

    States also have a responsibility to put more resources into this area and develop their expertise, if they want to see continued change at the federal level. States can do a lot, as Washington and Oregon have demonstrated by banning the installation of uncertified stove. Cities can restrict the installation of any wood stove and other solutions are emerging in Europe such as requiring electrostatic precipitators, whose prices are dropping rapidly. The Department of Energy (DOE), their national labs and universities can also play a vital role by supporting more R&D and pushing for the development of automated, computer generated stoves, something the EPA has paid little attention to.

    Wood and pellet stoves are not going away and provide a vital source of renewable heat to more than 10 million American homes. They have successfully helped America decarbonize residential heating far more than they get credit for. With increased R&D, innovation and regulatory oversight, wood and pellet heat can continue to help us achieve carbon reductions that are badly needed to stave off the worst impacts of global climate change. A key part of this process lies with the EPA by addressing many of the issues raised in the OIG report.

Friday, March 17, 2023

Wood smoke in low-income communities is an environmental justice challenge for the EPA

The Alliance for Green Heat, along with eight firewood banks across the nation that support the comment, submitted a response to the EPA's Request for Information on the Environmental and Climate Justice Block Grant Program (ECJ Program). This was a great opportunity to practice viewing wood heating through an environmental justice lens. Below is the submitted comment.

"Re: Environmental and Climate Justice Block Grant Program - Request for Information (Docket No. EPA-HQ-OEJECR-2023-0023)


The Environmental and Climate Justice Block Grant (ECJ) program presents an opportunity to address marginalized communities who primarily heat with wood and experience excessive wood smoke that is a health hazard. The EPA has neglected wood heating technology and wood heating regulations, contributing to thousands of communities living with excessive indoor and outdoor wood smoke.  

Wood heating communities include many tribes and also rural areas in the colder parts of the United States that have always relied on wood heat. The technology has stagnated, in part due to lack of attention by the EPA and DOE, who appear to regard wood stoves as an antiquated appliance relied on by poor households, and not worthy of development.  A recent report from the EPA’s Office of Inspector General found that the EPA wood stove certification program is broken, leaving consumers vulnerable to stoves that may have higher emissions than they should (EPA OIG, 2023).  For decades, under administrations of both parties, the EPA’s wood heater certification program has been underfunded and understaffed, jeopardizing those communities that rely most on wood heat, which include many of the poorest rural populations.   

The OIG report recognized the environmental justice issue in poor communities that primarily heat with wood, but it used data that obscures the extent of the problem. The EPA looked at all households, including urban ones, rather than focusing on income levels of rural homes that use wood. A very flawed study commissioned by the EPA in 2010 found that “the average risk from residential wood smoke is lower for people living on Tribal Lands than for the general population,” (Analysis of Exposure to Residential Wood Combustion Emissions for Different Socio-Economic Groups, 2010). Thus, the final 2015 NSPS, the updated wood stove regulations, found that there were no “disproportionately high and adverse human health or environmental effects on any population, including any minority, low-income or indigenous population,” (EPA, 2015).

As our country electrifies and looks to the heat pump to decarbonize heating, wood stoves will likely remain popular for some time or even increase in popularity. In rural areas, power outages are becoming more, not less common, and people are wary of relying solely on electric heat. In addition, for millions of households wood is a free fuel and despite the efficiency of a heat pump, wood will always be cheaper than electricity. There still does not appear to be the political will at the EPA to address the needs of LMI communities that rely on wood to heat their homes.  

We urge the EPA to consider funding programs that:

  1. Change out old wood stoves for heat pumps or newer wood stoves, depending on the needs of LMI households.

  2. Support Firewood Banks that help LMI households get seasoned wood, energy audits, repairs for dangerous wood stoves and ultimately trade up to cleaner heaters.

  3. Explore the development of affordable, computerized wood stoves that drastically reduce PM and give households the chance to heat with a renewable without excessive air pollution.

  4. Provide training to do health and safety inspections of wood stoves during energy audits. Currently, energy audits programs for LMI households are not equitable in inspecting wood stoves, as they do for fossil fuel heaters which are typically found in wealthier homes.  Wood heaters should not be treated as a second-class appliance. 

By funding such projects, the ECJ program will help achieve Justice40 Initiative objectives by investing in cleaner, renewable heating in rural, firewood dependent LMI communities.  

Comment addressing item (2) types of actions related to President Biden’s Justice40 Initiative

We recommend that the Environmental and Climate Justice Block Grant program consider how best to support the fuel poverty and resilience of wood heating populations due to their rural geographic location and socioeconomic status. 

Lower-income households rely on wood heating more than higher-income households (Figure 1). The reasons for this range from accessibility to affordability. In our work, we hear stories of burning kitchen cabinets as a last resort for heating a home. Stories of elder community members making the choice of whether they should pay for heat, pay for their prescriptions, or pay for groceries is not uncommon. 

Figure 1. Data from 2015 OIG analysis of U.S. Energy Information Administration data. 

The average household income of homes using wood as a primary heat source is $76,490, the second lowest of any heating category (above homes that lack a primary heat source and just below homes that use electric heating) (Figure 2). 

No. of HomesAverage Household Income
Utility Gas58,643,017$102,942
Fuel Oil5,426,218$102,019

Figure 2. ACS 1-Year Estimates-Public Use Microdata Sample. Average of US household income in past 12 months.

Energy production and distribution have created archetypal cases of environmental injustice—

mountaintop removal for coal mining in Appalachia, nuclear waste siting on Navajo reservations in the West, oil refineries in southern Louisiana. Another example is the incredibly high percentage of homes that still heat with wood in poor rural areas that have not yet become part of the fossil fuel age. Areas where the majority population identifies as Native American, particularly in the Southwest, are likely to either heat primarily with wood or find it as the second most popular heating fuel in the area. This further makes the case that regulating and supporting wood stove households is an environmental justice issue. For example, in Apache County, Arizona, nearly 54% of homes are heated with wood (U.S. Census Bureau, 2021) with 71% of people identifying as Native American (U.S. Census Bureau, 2020). In McKinley County, New Mexico, a similar story. Around 44% of homes heat with wood (U.S Census Bureau, 2021) and 78% of people identify as Native American (U.S. Census Bureau, 2020). In San Juan County, Utah, about 38% of homes are heated with wood (U.S. Census Bureau, 2021) as 50% of the population identify as Native American (U.S. Census Bureau, 2020). These are not the only examples that represent the important role wood heating plays in Native American populations. Acknowledging that wood is used for primary heating by only 1.4% of homes nationally, this is a staggering rate of wood burners for a certain population and one that should not be overlooked when discussing funding to rectify environmental injustice (U.S. Census Bureau, 2021). The map below illustrates the concentration of wood fuel users by highlighting the often rural geography of their location as well as the prevalence of wood fuel on Southwest reservations. 

Muyskens et al. 2023. “U.S. home heating is fractured in surprising ways: Look up your neighborhood.” Washington Post.  

Considering that there is legitimate concern over the capacity of our energy grid to handle increasingly harsh climate change-driven natural disasters (Climate Reality Project, 2022), wood stoves may help in some areas during the transition to electricity. Making sure wood stoves are safe to use in LMI households should be paramount. Maintaining realistic expectations for the performance of our energy grid, given that U.S. households experienced more electric disruptions in 2021 than the previous high level of disruptions in 2020 (U.S. Energy Information Administration, 2021), would ensure more energy resilient communities. In this way, wood stoves could play an empowering role for households that fear electric disruptions as well as the increasing costs (U.S. Energy Information Administration, 2023), and environmental concerns of natural gas (Jordan, 2022). 

Proper wood stove inspections, referrals for possible wood stove change-outs, and heat pump installation consultations when wood heat does not best serve a household anymore are needed. Multiple firewood banks that we have worked with have expressed interest in offering these services if they could secure funding to train volunteers to properly inspect and then facilitate the next steps to address the household’s needs. Firewood banks have an intimate view and partnership with fuel-poor households and are in a unique position to facilitate a more energy-equitable outcome. Because socioeconomic status and geography play such an intricate role in identifying environmental injustices, a mechanism to support firewood banks to provide these services would be of great help.

Providing households who struggle to keep their families warm with an emergency fuel source is one thing but ensuring that these families are using this fuel source in a safe wood stove appliance is another. We suggest that the ECJ grant funds programs address the reduction of indoor and outdoor air pollution, the prevention of house fires, and the repair or removal of wood stoves."

Signed By

Alliance for Green Heat 

Takoma Park, MD


Second Mesa, AZ

Pikunivi Wood Haulers

Second Mesa, AZ

Oglala Lakota Cultural & Economic 

Revitalization Initiative (OLCERI) 

Pine Ridge, SD

Kootznoowoo, Inc.

 on behalf of the village of Angoon, AK

Cullowhee UMC Project F.I.R.E.

Cullowhee, NC

Petersham Community Wood Bank

Petersham, MA

Rural Organizing and Resilience

Marshall, NC

St. Michael & All Angels Episcopal Church Wood Bank

Eureka, MT