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Wood smoke pollutionThe EPA’s Rules for New Residential Wood Stoves: A Sell-Out to the Wood Stove Industry?

On February 4, the EPA issued its long-awaited final rules for the manufacture and sale of new residential wood stoves. We weren’t fans of the proposed rule, and we think the final rule is even worse. After intense lobbying, the EPA caved to industry pressure, and the result is a rule that may do more harm than good to air quality.

Cordwood Testing: Up in Smoke

One of the biggest problems with the existing EPA wood stove certification process is that it uses kiln-dried lumber arranged in a crib formation. Since people don’t operate their wood stoves like this in the real world, the proposed EPA rule sought to address this by specifying the use of cordwood in the testing process.

Unfortunately, lobbying from the wood stove industry spurred the EPA to back away from this common sense step forward and to revert to testing with kiln-dried cribwood, not cordwood, for stove certification. This makes it impossible to extend the in-lab findings to the real world. Even in laboratory tests in controlled conditions, emissions from burning cordwood are higher than from burning cribwood (see studies here, here, and here), so in-home emissions will certainly be higher than projected.

Lower Wood Stove Emissions—But For How Long?

The EPA’s decision to lower allowed emissions from wood stoves in the new rules was applauded by health and environmental groups as a way to lower particulate matter (PM) emissions. But a closer look shows that this limit may have no effect—or even the opposite effect—on emissions in the longer term.

To meet these lowered emission limits, wood stove manufacturers are likely to use catalytic wood stove technology. Unfortunately, these catalytic components can break down in as little as two years. And when the components begin to wear out, the PM emissions increase dramatically. Stove maintenance is entirely voluntary; the proposed rule does not address the issues of degradation or proper maintenance of catalytic components.

Clearly there’s no economic incentive for the user of the stove to replace the catalytic components. There is also no functional reason for them to replace the catalytic components: the negative consequences of degraded catalytic components, which are primarily increased emissions, occur mostly outside the end user’s home. Thus, there is no reason to think that owners will replace the degraded catalytic components or expend the effort to maintain them properly.

The EPA states that the lifespan of a wood heater is over 20 years. Therefore, after a few years of use, wood smoke emissions from catalytic wood stoves will potentially be as high as those from an uncertified conventional wood heater. Thus, the unintended consequence of the EPA’s lower emissions limit is likely to be higher emissions.

The Long Phase-Out Period

After lobbying from the wood stove industry, the EPA settled on a generous (to industry) 5-year phase-out period for manufacturers to transition to the new standards and sell off their existing models.

The industry is already leveraging this extended transition as a way to gin up sales of wood stoves by making consumers feel like they must act now before the new EPA rules take effect (and prices increase). One ad for an outdoor wood boiler urges consumers to act now, claiming that they will only be available for a limited time:

Outdoor Wood Boiler Ad

VOCs and Air Toxics

In their summary of the final rules, the EPA claims that the lower emission limits will reduce VOC pollution. Unfortunately, as far as we’re aware, there is no scientific basis for this claim.

The new rules do not test for, or necessarily reduce, VOCs or air toxics (including formaldehyde, benzene, dioxins, and polycyclic organic matter). Importantly, studies show that these are not reduced in parallel with PM emissions (see here, here, and here). One technical report prepared for the EPA concluded, “The data demonstrate that particulate emissions cannot be used as a surrogate measurement for POM [polycyclic organic matter] emissions of woodstoves.”

The EPA’s mission is to protect human health, and this rule was originally intended to reduce wood smoke pollution to decrease the harmful effects of wood smoke. Unfortunately, we have several reasons to fear that these measures may make things even worse.

A Lack of Natural Gas Service is No Longer an Excuse for Wood Burning

Many rural areas in the US still lack natural gas service, and these areas often have the highest rates of residential wood burning (and the highest wintertime air pollution).

The reliance on wood burning for home heating in these areas is rationalized on the basis that the cost of electric heat or propane is too expensive. This rationale has even held sway with air quality regulators, who have exempted areas not serviced with natural gas from wood burning restrictions on days when the air quality is poor or predicted to be poor (see, for example, the policies of the San Joaquin Valley and the San Francisco Bay Area Air Districts).

But now, thanks to advances in technology, heating a home with an electric split ductless heat pump is cheaper than heating with natural gas (see here, here, and here). Sensiblenergy.com provides a detailed four-part comparison of the cost of heating a moderate-sized house in Portland, Oregon using gas vs. oil vs. electricity. (Part 4 is here with links to the other parts.) The conclusion? Using a split ductless heat pump is the cheapest of these options.

Split ductless heat pumps are extremely efficient because they move heat from one place to another rather than generating heat from energy. (A more detailed explanation of how they work can be found here.) Installation does not require ductwork, which can be expensive and difficult to put in. In fact, the cost to purchase and install a split ductless unit is comparable to the purchase and installation of a wood stove. Note that these units can cool as well as heat–try doing that with a wood stove.

Wood burning is one of the most damaging activities an individual can do in terms of the impact on the health of their neighborhood. Now there’s one less excuse for doing it.

Study Shows Wood Smoke Pollution Levels Vary Widely Within a Neighborhood

Proving once again the real estate mantra, “Location, Location, Location,” an important new study raises serious concerns that wood smoke pollution at some residential locations is much higher than previously estimated. Specifically, the study reports huge variations in the exposure levels to wood smoke at different locations within a single neighborhood.

In this well designed field study funded by the California Air Resources Board (CARB), researchers compared measurements of wood smoke pollution within a one-kilometer area of a small California coastal town. The sampling occurred on 15 nights over two winter seasons. Notably, the town has no significant sources of air pollution, such as traffic or industry, other than residential wood combustion.

The researchers found that there were large variations in wood smoke pollution levels even within this small area. How large? Measurements in some locations were up to 300% higher than the area average.

This means that people living in the same neighborhood are being exposed to radically different levels of hazardous air pollution—and that some unfortunate households are being exposed to much higher air pollution levels than shown by centrally located air monitors.

This study illustrates why central air monitoring, which reports the average particulate pollution at a single location, is not an effective tool for measuring wood smoke pollution.

It also lends urgency to the recent call by Utah Physicians for a Healthy Environment to ban wood burning in densely populated areas.

Families for Clean Air Now Part of Amazon Smile

We’re happy to announce a new way to support Families for Clean Air. The good news is that it won’t cost you a penny. That’s because Families for Clean Air is now part of the Amazon Smile program, which will donate money whenever you shop on Amazon.

It only takes a minute to sign up, and after you do it, 0.5% of the cost of your Amazon purchases will be donated to Families for Clean Air. You can read more about how the program works here, but the main point is that all Amazon pricing, products, and services (including Amazon Prime) will remain the same to you, but you’ll now be supporting our efforts to protect public health from wood smoke pollution through education, advocacy, and community involvement.

Families for Clean Air is a 501(c)3 organization. All of our funding comes from donations from people like you—people who agree that everyone has the right to breathe clean air.

Families for Clean Air’s Comments on the New EPA Wood Burning Rule

The EPA’s proposed rule on wood burning devices has generated significant media attention, controversy, and misinformation (most of it created intentionally).

The public comment period on the proposed rule ended on May 5, 2014, and the EPA now has nine months to finalize the new rule (found here).

The proposed rule was issued in the wake of lawsuits brought by several states and public health organizations. The lawsuits charged that current federal standards were not adequately protecting people from the pollution produced by wood burning devices.

While Families for Clean Air appreciates that the proposed EPA rule addresses some shortcomings of the existing rule, serious concerns remain. You can find out what these concerns are by reading the comments that Families for Clean Air submitted to the EPA.

We urge you to give FCA’s comments a read.