1. (1) Vapor pressure. Vapor pressure standards set forth in 6 NYCRR Subpart 225-3, or exceptions granted thereto by the Commissioner of Environmental Conservation, shall supersede those in this section.

2. (2) Gasoline-alcohol blends.

   1. (i) Gasoline-ethanol blends greater than 15 percent by volume and less than 51 percent by volume ethanol are prohibited. Only gasoline-butanol blends may contain 16 percent alcohol by volume.
   2. (ii) When methanol is blended with gasoline in quantities greater than three-tenths (0.3) percent by volume, the finished blend shall contain at least an equal amount of butanol or higher molecular weight alcohol, or other approved co-solvent. The maximum methanol content of any gasoline shall not exceed five percent by volume.
3. (3) Motor octane number. All unleaded gasoline with minimum (R + M)/2 octane ratings of 87 or higher shall have minimum motor octane number of 82. Unleaded gasolines with minimum (R + M)/2 octane ratings less than 87 shall have a minimum motor octane number of 81.5.

4. (4) Testing for octane rating. To determine the automotive fuel rating (octane rating) for gasoline in this Part, add the research octane number from test method ASTM D 2699-15a and the motor octane number from test method ASTM D 2700-14 and divide by two as explained in ATSM D 4814-18a. Variations in test results for octane ratings within the ASTM reproducibility limits shall be recognized in the enforcement of this section. No violation shall be issued for failure to meet a certified or posted octane rating unless the laboratory test results are:

   1. (i) more than seven-tenths (0.7) octane less than the certified or posted octane for octane ratings less than 89; or
   2. (ii) more than six-tenths (0.6) octane less than the certified or posted octane rating for octane ratings of 89 or greater.

5. (5) Leaded gasoline. All automotive gasoline designated as “leaded” shall contain a minimum of 0.05 gram per gallon and a maximum of 0.1 gram per gallon of lead, or a minimum of 0.005 gram per gallon of phosphorus.

   (b) Diesel fuel.

   All diesel fuel shall meet the requirements in ASTM D 975-18.

   (c) Kerosene.

   All kerosene shall meet the requirements in ASTM D 3699-13.

6. (d) Denatured fuel ethanol intended for blending with gasoline shall meet the requirements in ASTM D 4806-19a.

   1. (1) Ethanol flex fuels containing 51 to 83 percent ethanol by volume shall meet the requirements in ASTM D 5798-19b.

   2. (2) Ethanol flex fuels containing more than 10 percent but not greater than 15 percent ethanol by volume shall meet the requirements in ASTM D 4814-18a.

      (f) Butanol.

      All butanol intended for blending with gasoline shall meet the requirements in ASTM D 7862-17.

      (g) Butanol blends.

      Blends of butanol and gasoline that contain less than or equal to 16 percent butanol by volume, shall meet the requirements in ASTM D 4814-18a.

      (h) Biodiesel.

      All biodiesel intended for blending with diesel fuel shall meet the requirements in ASTM D 6751-15c.

      (i) Biodiesel blends.

      All blends of biodiesel and diesel fuel shall meet the following requirements:

   3. (1) Blends that contain 5 percent or less biodiesel by volume shall meet the requirements in ASTM D 975-18.
   4. (2) Blends that contain more than 5 percent biodiesel by volume but 20 percent or less biodiesel by volume shall meet the requirements in ASTM D 7467-18
   5. (3) When blends that contain more than 20 percent biodiesel are offered for sale, the diesel fuel used in the blend shall meet ASTM D 975-18 and the biodiesel blend stock shall meet ASTM D 6751-15c.

   (e) Ethanol flex fuels.

   All blends of ethanol flex fuel shall meet the following requirements:

The following products when sold, offered for sale or when used in this State shall meet the following requirements:

(a) Automotive gasoline.

All automotive gasoline shall meet the requirements in ASTM D 4814-18a, except as noted below.