Who is affected and how:

• Vessel operators and shipowners: Face direct obligations to meet carbon-intensity limits for fuels on covered voyages and to comply with at-berth/at-anchorage emission rules. This may require switching to lower-carbon fuels, adopting on-board emissions control technology, changing operational practices, or participating in averaging pools. They will also bear monitoring, reporting, and potential enforcement costs.

• Maritime carriers, shippers, and charterers: May see increased transport costs as operators pass through costs for cleaner fuels, retrofits, or operational changes. Contracting and scheduling may change to meet compliance windows or to use compliant suppliers.

• Port authorities and terminal operators: Will be affected by in-port emission elimination requirements through changes in vessel operations while at berth or anchor. Ports may need to coordinate shore power availability, berth scheduling, or other infrastructure to support compliance. Ports may also see public health benefits from reduced local air pollution.

• Marine fuel suppliers and refiners (proposed): Will need to produce, certify, and supply lower-carbon marine fuels compliant with EPA’s carbon-intensity standard. This could shift demand across fuel types (e.g., lower-carbon blends, biofuels, alternative fuels) and require new testing/verification services.

• Local communities and public health: Communities near ports and anchorages could experience reduced local air pollution (NOx, SOx, PM, and others) if the at-berth/at-anchor rules drive elimination or large reductions in emissions, improving air quality and public health outcomes.

• Regulators and compliance service providers: EPA will need to develop technical standards, monitoring and reporting systems, and enforcement procedures. Private compliance auditors, fuel testing labs, and legal/regulatory advisors may see increased demand.

Net effects and risks:

• Environmental benefits: Clear potential to reduce greenhouse gas intensity of marine fuels and to cut harmful in-port air pollution, supporting climate and public health goals.
• Economic/operational costs: Ship operators and fuel suppliers will incur costs to comply, which may raise shipping prices and require capital investments in ships, fuel infrastructure, or emissions-control technologies.
• Technical and international alignment issues: Implementation will depend on available low-carbon fuels and technology; harmonization with international standards can ease trade and compliance but may be difficult to coordinate.
• Feasibility safeguards: The feasibility clause provides EPA discretion to avoid impossible requirements, but it can also introduce regulatory uncertainty for industry during rulemaking.

Overall, the legislation shifts regulatory responsibility to EPA to set detailed standards and deadlines; compliance will mainly burden the maritime industry and fuel suppliers while delivering environmental and public health benefits if standards are met.