EPA Proposes to Relax Gasoline Cargo Tank Vapor Tightness Requirements

Thursday, September 24, 2026 – EPA proposed today to relax the gasoline cargo tank vapor tightness certification requirements it adopted in 2024, responding to concerns raised by EMA. Specifically, EPA proposes to replace the 2024 limits with the graduated pressure-drop limits of 1.0 to 2.5 inches of water column, depending on cargo tank compartment size, that applied under NESHAP Subpart R before the 2024 final rule. The proposal follows extensive EMA advocacy before EPA and Congress regarding the technical feasibility and operational impacts of the 2024 requirements.

The 2024 final rule established a graduated pressure-drop limit of 0.5 to 1.25 inches of water column over a five-minute test period, depending on compartment size, which was significantly more stringent than the prior standards. EMA raised concerns that limits at the low end of that range could not be reliably demonstrated using EPA Method 27 under real-world operating conditions. EMA provided EPA with information and data regarding the difficulties experienced by fuel marketers and cargo tank operators, including the effects of temperature fluctuations and limitations in the test method that could result in false test failures, unnecessary retesting, and premature equipment replacement. EMA also documented the costs of meeting the 2024 standard, including retrofits, repairs, and operational downtime.

EMA brought these concerns to Congress as well. In March 2026, Senator Kevin Cramer (R-ND), joined by Senate Environment and Public Works Committee Chairman Shelley Moore Capito (R-WV) and nine other Senators, urged EPA Administrator Lee Zeldin to reverse the 2024 cargo tank vapor tightness requirements and restore the prior testing standard.

EPA's proposal recognizes many of the technical concerns raised by EMA. The Agency notes that EPA Method 27 has a reported precision of ±0.5 inches of water column and that a temperature change of approximately 1°F can produce a pressure change exceeding 0.5 inches of water column. EPA therefore proposes to find that the 0.5-inch requirement is at the limit of the test method's precision and that the more stringent requirements adopted in 2024 are not achievable in practice nationwide. EPA also preliminarily concludes that the incremental costs associated with the 2024 requirements are unlikely to be cost-effective under reasonable alternative assumptions.

EMA will continue its advocacy throughout the rulemaking process. EMA intends to submit comments supporting EPA's proposed revisions and will provide additional data and information from fuel marketers and cargo tank operators regarding the practical challenges of complying with the 2024 standard. Members with test results, retesting or repair costs, or other relevant experience are encouraged to share that information with EMA. The Association will continue working with EPA and Congress to ensure that the final requirements are technically feasible, cost-effective, and capable of being reliably demonstrated under EPA's testing procedures. Until EPA issues a final rule, the 2024 requirements remain in effect.

“EMA commends EPA for addressing the challenges posed by the infeasible 2024 vapor tightness standard, and we thank the members of Congress who have continued to elevate this issue and support America’s small business fuel marketers,” said EMA President Rob Underwood.