AZ HB2955

Establishes seasonal gasoline formulation requirements for Arizona's Area A (counties with 1.2+ million population), requiring ASTM D4814 standards from April 1 through October 31 and California Phase 2 reformulated gasoline standards from November 1 through March 31.

Applies similar seasonal requirements to Area C, requiring ASTM D4814 compliance from April 1 through October 31 with maximum vapor pressure requirements.

Allows registered fuel suppliers to petition for alternative fuel standards when facing imminent supply shortages of ethanol or compliant gasoline, with petitions valid for up to 60 days and reauthorizations for up to 30 days.

Requires EPA approval of the modifications to Arizona's state implementation plan for air quality by July 1, 2030 for the changes to take effect.

Exempts fuel sold for motor vehicle manufacturer proving grounds and racing events from these reformulation requirements.