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Regulatory Announcement: Highway Heavy-Duty Diesel Engine Regulatory Amendments
EPA420-F-06-059, August 2006
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The U.S. Environmental Protection Agency (EPA) is publishing a Direct Final Rule to incorporate some technical amendments to regulations related to highway heavy-duty diesel engines.
- Background
- Additive Deterioration Factor Option for Heavy-Duty Diesels
- Additional Provisions
- Public Participation Opportunities
- For More Information
Background
EPA initiated this rulemaking change to improve the technical approach in the current regulations and to add a provision to allow highway diesel engine manufacturers the ability to use an additive deterioration factor as default for heavy-duty highway diesel engines. This change to the rule would harmonize our approach for highway heavy duty with the approach we took for nonroad diesel for the same technologies in 1039.240(c)(1). It is only an option that requires use of good engineering judgment and manufacturers are not required to use an additive DF.
Additive Deterioration Factor Option for Heavy Duty Diesels
This Direct Final Rule establishes deterioration factor provisions applicable to a highway heavy-duty engine identical to the options available to nonroad certified heavy-duty diesel engines certified under 40 CFR 1039.240. Additive deterioration factors are already allowed for chassis-certified heavy-duty engines between 8,500 and 14,000 pounds gross vehicle weight rating (GVWR). The new provision:
- Adds additive deterioration factors for heavy-duty diesel engines equipped with aftertreatment.
- Requires the use of multiplicative deterioration factors if, based on good engineering judgment, they are more appropriate for a particular engine family.
- Streamlines and harmonizes the calculation method for deterioration factor determination.
There is no environmental impact associated with this regulatory action. This rulemaking does not change the heavy-duty highway diesel engine emission standards that manufacturers have to meet or the requirement that these standards be met throughout the useful life of the engines. Rather, this action provides an option for manufacturers regarding how they can calculate the projected deterioration of the engines emissions. In addition, EPA does not expect that these minor revisions will have any adverse cost impact to the manufacturers, and there are no new testing costs associated with these revisions.
Additional Provisions
This rule also includes changes to EPA's regulations which:
- codify existing Agency policy
- update certification fee regulations
- update OBD regulation references
Public Participation Opportunities
This rule is being released as a direct final rule because we view it as a non-controversial action and anticipate no adverse comment. However, comments can be submitted under a parallel Notice of Proposed Rulemaking. For instructions on submitting written comments, please see the Federal Register notice, which is available from the Web site below or from the EPA Air and Radiation Docket (202-566-1742; please refer to Docket No. EPA-HQ-OAR-2005-0474). You can access the rule and related documents on EPA's Office of Transportation and Air Quality (OTAQ) Web site at:
For More Information
For more information on this direct final rule, please contact the Assessment and Standards Division at:
U.S. Environmental Protection Agency
Office of Transportation and Air Quality
Assessment and Standards Division
2000 Traverwood Drive
Ann Arbor, MI 48105
Voice-mail: (734) 214-4636
E-mail: asdinfo@epa.gov