Many states that use ASTM International guidelines have decided to delay implementation of a ruling that would require, effective Jan. 1, a minimum amount of lubricating qualities in diesel fuel, industry officials said.

Industry experts said the U.S. Environmental Protection Agency’s recent assessment of airborne particulate matter could support the tightening of ambient air particulate-matter standards when the agency reviews those standards later this year.

The Federal Aviation Administration will develop a plan by Dec. 31 to speed investigations and encourage air carriers to voluntarily report hazardous materials violations, in the wake of a recent report by the U.S. Department of Transportation’s inspector general criticizing the agency’s monitoring of hazardous materials, an FAA spokeswoman said..

A California Air Resources Board regulation scheduled to take effect Dec. 10 would require diesel-fueled transport refrigeration units operating in that state to meet certain emission requirements by 2008.

The largest U.S. pipeline operator, Colonial Pipeline, said it plans to ban diesel fuel with lubricity additives from its system, which would require the oil industry to spend millions of dollars to equip their terminals to add the chemicals. Others are likely to follow.

NEW ORLEANS — Officials at pipeline companies and fuel retailers said they would have to change fuel-distribution patterns, and be careful when loading or storing ultra-low-sulfur fuel, to avoid its being contaminated by fuel with higher sulfur content to an extent that the ULSD would fail to meet government standards.

NEW ORLEANS — Ultra-low-sulfur diesel fuel is going to have to leave refineries at well below new federal sulfur-content levels for 2006 because contamination as it moves through pipelines is inevitable, according to refiners, pipeline operators and environmental officials.

A spokeswoman for the California Air Resources Board said that it had received more than 3,000 comments on whether or not it should seek a waiver from federal Clean Air Act rules so that a Southern California air-quality agency could require public fleets to buy cleaner-running engines.

The National Highway Traffic Safety Administration expects to release by year’s end a proposed rule that would start the formal process to shorten the required stopping distances for heavy-duty trucks, an agency spokeswoman said.

A group of trucking industry representatives could be ready by early next year to ask Congress to provide financial incentives encouraging the use of engines that meet 2007 federal emission standards, industry officials said.