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Gasoline Standards

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Direct Final Rule: Modifications to Standards and Requirements for Reformulated and Conventional Gasoline Including Butane Blenders and Attest Engagements Additional Resources

Fact Sheet: EPA Issues a Direct Final Rule to Modify Certain Provisions of the Reformulated and Conventional Gasoline Regulations Including Provisions for Butane Blenders and Attest Engagements (PDF) (5 pp, 228 K, EPA420-F-05-030, December 2005)
Direct Final Rule (PDF) (29 pp, 233 K, published December 15, 2005)

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Butane Blending Technical Analysis (PDF)(8 pp, 140 K, 4/28/03)