More on Emissions: Where to Now for Diesels?
EPA Seeks Small-Business Input on Phase 3 GHG Rules for Trucks, Buses
The U.S. Environmental Protection Agency is inviting small businesses to give it feedback on the agency's proposed Phase 3 greenhouse gas emissions rules.

EPA says zero-emissions vehicles will be an important part of its Phase 3 greenhouse gas regulations.
Photo: GNA/ACT Expo
The U.S. Environmental Protection Agency is inviting small businesses to give it feedback on the agency's proposed Phase 3 greenhouse gas emissions rules.
EPA is looking for "Small Entity Representatives" to participate on a Small Business Advocacy Review Panel. This panel will focus on the agency’s development of a rule that proposes to set a new phase of greenhouse gas requirements for heavy-duty engines and trucks that would apply beginning in model year 2030.
EPA first adopted GHG requirements for heavy-duty vehicles in 2011. The Phase 1 rule created a new certification and compliance program based on the computer simulation of vehicle carbon dioxide emissions and fuel efficiency rather than emissions and fuel efficiency testing, set performance-based standards, and adopted interim provisions to address impacts on small businesses. The Phase 1 standards began to apply in model-year 2014 for heavy-duty vehicles.
In 2016, EPA adopted a Phase 2 rule that set more stringent CO2 standards, as well as limits for hydrofluorocarbon, methane, and nitrous oxide (three other greenhouse gases.) The Phase 2 standards began to apply in model-year 2021. The Phase 2 rule also updated the prescribed emission simulation model to account for additional and new fuel-saving technologies and included flexibilities for small businesses that were identified by an SBAR Panel for that rulemaking.
This Phase 3 proposal would revise the GHG emission limits for heavy-duty vehicles while relying on the same basic certification and compliance structure already in place. The Phase 3 proposed rulemaking changes are expected to include more stringent vehicle emission standards to apply beginning in model-year 2030, based on revised projections of GHG-emission-reduction technologies used by engine and vehicle manufacturers, including future technology development. In developing the new standards, EPA will consider what it calls “the important role of zero-emission vehicle (ZEV) technologies to significantly reduce air pollution from the heavy-duty vehicle sector.”
The proposal also would include “limited and targeted flexibilities for small businesses,” thus the desire for small-business input.
The panel will include federal representatives from the Small Business Administration, the White House Office of Management and Budget, and EPA. The panel members ask a selected group of “Small Entity Representatives” to provide advice and recommendations on behalf of their company, government, or organization to inform panel members about the potential impacts of the proposed rule on small businesses.
EPA is looking for self-nominations directly from small businesses that may be subject to the rule requirements. Other representatives, such as trade associations that exclusively or at least primarily represent potentially regulated small entities, may also serve as SERs.
Self-nominations must be received by Aug. 29.
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