It’s been 26 years since the Environmental Protection Agency last updated its emission standards for wood stoves. Even so, it is likely that many of the wood stoves that were burning during the last update are still heating homes today.

The EPA is proposing that the emission limit be lowered from 7.5 grams per hour of fine-particle pollution to 1.3 grams per hour by 2019. That would require some adjustment by manufacturers, which now make most wood stoves under the threshold of 4.5 grams per hour, a de facto national standard based on a strict law passed in Washington state.

The real challenge, however, is getting homeowners, now used to having wood as their only heating cost, to replace older, dirtier stoves for the sake of energy efficiency and cleaner air. Tougher emission standards may lead to long-term gains, but the newest, sleekest wood stoves won’t do any good in the showroom.

Tax rebates and incentives have had a little success in getting consumers to swap out old wood stoves, but public resources for those programs are tight. That’s why Maine and other states whose residents use wood heat at a high rate should try more targeted programs that reach out to the worst offenders. At the same time, supplementary efforts can help homeowners with older stoves use them as efficiently as possible.

Fourteen percent of Maine households heat primarily with wood — second only to Vermont — and many more use wood as backup, according to U.S. Census figures. Wood as a source of heat grew in popularity from 2000 to 2010, by 34 percent nationwide and 96 percent in Maine. And not all of the newcomers to wood heat are buying new stoves — many are firing up older ones that had been left idle.

At the same time, Mainers suffer at a high rate from the kinds of health issues, such as asthma and chronic obstructive pulmonary disease, made worse by fine-particle pollution, one of the main sources of which is burning wood.

That has led seven states — though not Maine — to threaten a lawsuit to urge the EPA to revise its standards. Manufacturers, however, argue that the stricter standards will push up the cost of wood stoves to the point at which they’d be unaffordable to low-income residents.

Clean air should be the priority, and a lower emission standard will push manufacturers, if reluctantly, to produce wood-burning equipment that is clean, efficient and affordable. Meanwhile, federal and state incentives should be offered to the extent possible to encourage residents to voluntarily turn in their old stoves for new ones. A $300 federal rebate has run out, but Efficiency Maine offers a $250 rebate. Jotul, a manufacturer with a plant in Gorham, has offered its own $300 credit.

Funding for these programs is always tight, so perhaps Maine should target its efforts at the areas of the state where the pollution is the worst. The Department of Environmental Protection should monitor air quality in areas such as valleys, where pollution tends to sit without circulating. The state then could focus its clean-air efforts first on those areas.

At the same time, the state should investigate whether it is cost-effective to offer incentives for wood-burning Mainers to build protective sheds for wood piles, as dry wood burns much more cleanly than wet.

Implementing these policies together will mean Mainers won’t have to choose between clean air and affordable heat.