BOSTON — The commissioner of the Maine Department of Environmental Protection says proposed restrictions on burning wood are a concern for Mainers.

Commissioner Patricia Aho says stricter emission requirements outlined in a draft rule by the Environmental Protection Administration could be prohibitively expensive in a state that relies on wood for heating.

In a public hearing Wednesday in Boston, she said the draft rule did not include all types of wood stoves and placed the burden of compliance on the shoulders of an aging Maine population. She noted that many residents burn wood because it is less expensive than heating oil.

The draft rule is the first time the EPA has update residential wood heating standards since 1988. It is set to become law in 2015.