Greenhouse Gas Emissions Model Updated

The Environmental Protection Agency is tweaking its emissions compliance standards for heavy-duty engines and associated new vehicles, but the downstream implications are expected to be minimal.

The EPA issued a final rule June 28 detailing revised procedures for “demonstrating compliance with the CO2 emission standards for heavy-duty highway engines and vehicles.” The rule, which was posted in the Federal Register, applies to manufacturers and retailers of heavy-duty engines and the vehicles they power.

The changes apply to the Greenhouse gas Emissions Model (GEM) compliance evaluation tool, with a new update correcting issues found with older versions of the program. Specifically, these amendments would modify the existing test procedure to include adjustment factors.

The new testing procedures take effect Aug. 29, according to the rule.

“Given the nature of this rule, there will be neither significant environmental impacts nor significant economic impacts,” reads the listing.