The sweeping federal proposal to cut greenhouse-gas emissions and raise fuel efficiency for medium- and heavy-duty trucks over the next decade prompted qualified support, an outcry over poor air quality and calls for zero-emissions technologies at a public hearing Aug. 18 in Long Beach, California.

A report on the proposed Phase 2 greenhouse-gas rules found 87% of medium- and heavy-duty fleet operators surveyed earlier supported increased fuel efficiency and fewer emissions because the changes would also reduce what typically is trucking’s second-biggest expense, fuel.

Federal regulators on July 13 formally published their proposal in the Federal Register that would tighten greenhouse-gas emissions for trucks, improve their fuel economy and regulate trailer efficiency for the first time.

Suppliers of fuel-saving technologies for trucks and trailers said they expect their products will increasingly be installed at the factory level under the federal government’s proposed Phase 2 greenhouse-gas standards.

WASHINGTON — The Environmental Protection Agency and the Obama administration as a whole will continue to emphasize their campaign against climate change from carbon emissions, even if all aspects of useful technologies are not known at present.

The federal government has issued its long-awaited proposal to further tighten greenhouse-gas emissions from heavy- and medium-duty trucks, and for the first time regulate trailer efficiency.

Trailer manufacturers said the initial goals of the federal government’s first-ever proposal for trailer efficiency standards will be attainable through existing technologies.