Maine’s Board of Environmental Protection did the right thing Thursday when it adopted tougher emission standards for new cars and trucks.

The new rules will bring the state into line with California, New York, Washington, Oregon and Vermont, which have already adopted the standards, and are expected to reduce greenhouse gas emissions by 30 percent by 2016.

Automobiles are responsible for 40 percent of all greenhouse gas emissions in Maine. The board’s vote is a step forward in protecting the environment, cutting pollution and improving public health.