2VAC5-480-70. Sampling, testing, and oxygen content calculations.
A. Sampling methodologies used by the commissioner to determine compliance with this chapter shall be those set forth in Appendix D, 40 CFR Part 80, which is hereby adopted by reference.
B. Determination by the commissioner of the oxygenate and its weight and volume in gasoline shall be in accordance with test method ASTM D 4815-89 as set forth in ASTM specification D 4814 or other methods developed or approved by the United States Environmental Protection Agency.
C. Oxygen content shall be calculated by the commissioner by multiplying the mass concentration of each oxygenate in gasoline by the oxygen molecular weight contribution of the oxygenate. All volume measurements shall be adjusted to 60 degrees Fahrenheit. For the purpose of calculating oxygen content, the following oxygen molecular weight contributions shall be used:
Oxygenate | Oxygen Mass Fraction | Relative Density |
Methyl Alcohol | 0.4993 | 0.7963 |
Ethyl Alcohol | 0.3473 | 0.7939 |
n-Propyl Alcohol | 0.2662 | 0.8080 |
Isopropyl Alcohol | 0.2662 | 0.7899 |
n-Butyl Alcohol | 0.2158 | 0.8137 |
Isobutyl Alcohol | 0.2158 | 0.8058 |
sec-Butyl Alcohol | 0.2158 | 0.8114 |
tertiary-Butyl Alcohol | 0.2158 | 0.7922* |
Methyl Tertiary-Butyl Ether | 0.1815 | 0.7460 |
Ethyl tertiary-Butyl Ether | 0.1566 | 0.7452 |
tertiary-Amyl Methyl Ether | 0.1566 | 0.7752 |
tertiary-Hexyl Methyl Ether | 0.1377 | 0.7860 |
Dilso propyl ether 0.1566 | 0.1566 | 0.7300 |
*Extrapolated, below freezing temperature. |
D. Oxygenated gasoline shall consist of a single homogenous mixture, presenting no indication of phase separation when tested by the commissioner in accordance with the test method described in Annex A3 of ASTM Specification D-4814.
1. -8°C (17°F) during the month of January.
2. -7°C (19°F) during the month of February.
3. -3°C (26°F) during the month of March.
4. 3°C (37°F) during the month of April.
5. 9°C (48°F) during the month of May.
6. 10°C (50°F) during the months of June, July, August, and September.
7. 4°C (39°F) during the month of October.
8. -2°C (28°F) during the month of November.
9. -7°C (19°F) during the month of December.
Statutory Authority
§§ 59.1-153 and 59.1-156 of the Code of Virginia.
Historical Notes
Derived from VR115-04-28 § 7, eff. November 1, 1993.