EPA Orders Emissions System Warnings

The Environmental Protection Agency mandated yesterday that manufacturers of heavy diesel trucks and buses install dashboard lights by 2010, like those devised for cars more than a decade ago, to signal whether emissions control equipment is malfunctioning.

The equipment is meant to help enforce compliance with pollution limits that the government tightened last year. The EPA has estimated that those limits, which lower emissions of particulate matter, sulfur dioxide, carbon monoxide and nitrogen oxides, will prevent 8,300 premature deaths and more than 9,500 hospitalizations, bringing $70 billion worth of health benefits in exchange for annual expenses totaling $2.3 billion.

The Bush administration's mandate came three months after the EPA approved California's request for legal authority to demand that the state's 400,000 diesel trucks install the new warning lights and related computer equipment. "EPA believes that a consistent nationwide . . . program is a desirable outcome," the agency said in its statement announcing its final regulation.

Steve Albu, assistant chief of the Mobile Source Control Division of the California Air Resources Board, said that although the state has been working in tandem with the EPA, California's rules set a slightly lower threshold for some emissions before the warning lights flash. He said that he now expects most engine manufacturers around the nation to install a single monitoring system that meets the state requirement.

The announcement is the culmination of a lengthy regulatory process. The EPA began considering the rule in 2006 and submitted a draft final review to the White House in October. But the agency was asked by the Office of Management and Budget to withdraw the regulation from formal interagency review on Nov. 10 because there were "too many other things they are working on" as Bush's tenure draws to a close, said Margo Oge, director of the EPA Office of Transportation and Air Quality.

The OMB said that the EPA could publish the rule anyway, and its decision was hailed yesterday by environmentalists. "It's the rare positive eleventh-hour Bush administration rule," said Frank O'Donnell, the president of Clean Air Watch, a nonprofit advocacy group.