By Richard Nemec, NGI Daily's Gas Price Index.

In California earlier this month, the South Coast Air Quality Management District (SCAQMD) board voted to petition the federal government to adopt tougher emission standards for large trucks to help the region meet its clean air goals. Heavy-duty trucks are the largest source of smog-forming emissions in the four-county air district.

"The technology for these reductions is available," said SCAQMD Chairman William Burke."The federal government needs to step up and require near-zero emission standards for all new trucks nationwide."

SCAQMD officials point out that the district has led an effort the past three years to develop near-zero emission CNG engines for refuse-hauling trucks. The 8.9-liter engine, produced by Cummins Westport Inc., recently won certification from the California Air Resources Board (CARB) (see Daily GPI, Oct. 8, 2015).