The Environmental Protection Agency (EPA) is taking direct final action on several amendments involving technical clarifications for different mobile source regulations. First, we are making a variety of corrections to the Tier 3 motor vehicle emission and fuel standards. These changes generally correct or clarify various provisions from the Tier 3 rule without expanding the Tier 3 program or otherwise making substantive changes. Second, we are revising the test procedures and compliance provisions for nonroad spark-ignition engines at or below 19 kW (and for the corresponding nonroad equipment) to conform to current practices. The changes to evaporative emission test procedures also apply to some degree to other types of nonroad equipment powered by volatile liquid fuels. Third, we are addressing an ambiguity regarding permissible design approaches for portable fuel containers meeting evaporative emission standards. Fourth, we are revising the regulations to more carefully align with current requirements that apply to marine vessels with diesel engines as specified under MARPOL Annex VI. Fifth, we are correcting typographical errors in regulatory changes finalized in the Voluntary Quality Assurance Program rulemaking. This rulemaking action is not expected to result in any significant changes in regulatory burdens or costs.