Industrial Strategies Division
Gasoline Historical Documents
| Title | Description | Year |
|---|---|---|
| Gasoline CARBOB Commingling Issues | A letter was received by the California Air Resources Board staff that asked questions about CARBOB commingling issues. The Enforcement Division responded to the letter and the response is provided. | 2009 |
| Cleaner Burning Gasoline: An Update | Fact Sheet that contains the latest information on cleaner burning gasoline. | 2006 |
| Cleaner Burning Gasoline without MTBE | Fact Sheet that contains information about the phase out of MTBE from California gasoline. | 2003 |
| Federal Reformulated Gasoline (RFG) | Federal Reformulated Gasoline (RFG) is required in severe ozone non attainment areas pursuant to the Federal Clean Air Act Amendments (FCAA) of 1990. | 2002 |
| Health and Environmental Assessment of the Use of Ethanol as a Fuel Oxygenate | Report by California agencies (CARB, SWRCB, OEHHA) evaluating the impacts of replacing MTBE with ethanol in gasoline. | 1999 |
| Ethanol Fate, Transport, and Health Risk Analysis | Executive Order D-5-99 required California Air Resources Board (CARB) to adopt gasoline regulations to phase out MTBE, and required CARB, the Office of Environmental Health Hazard Assessment (OEHHA), and the State Water Resources Control Board (SWRCB) to conduct an ethanol fate, transport, and health risk analysis. | 1999 |
| Ethanol Archive | Evaluation of ozone-forming potential of elevated Reid Vapor Pressure (RVP) gasoline containing 10 volume percent ethanol. | 1998 |
| California Reformulated Gasoline Phase 3 (CaRFG3) | Implemented in 1999, eliminated methyl tertiary-butyl ether (MTBE) from California gasoline. | 1999 |
| California Reformulated Gasoline Phase 2 (CaRFG2) | Implemented in 1996, set specifications for sulfur, aromatics, oxygen, benzene, T50, T90, Olefins, and RVP and established a Predictive Model. | 1996 |
| California Reformulated Gasoline Phase 1 (CaRFG1) | Implemented in 1992, eliminated lead from gasoline and set regulations for Deposit Control Additives and Reid Vapor pressure (RVP). | 1992 |
Gasoline Program Requirements
Gasoline Predictive Models and Procedures
Regulatory tool that uses a set of mathematical equations allowing gasoline producers, importers, and small refiners to create alternative, flexible formulations of California Reformulated Gasoline (CaRFG) that ensure equivalent or greater emission reductions compared to traditional standards.
Gasoline Predictive Models and CARBOB Model Development
Gasoline Reid Vapor Pressure Requirements
One of the eight specifications required by the California Gasoline Regulations that requires a standard for Reid Vapor Pressure (RVP), which is designed to reduce evaporative emissions during the summer months when ambient temperatures are their highest.
Gasoline Oxygenates
Oxygenates are chemical compounds (usually alcohols or ethers) added to gasoline to increase oxygen content, promoting cleaner, more complete combustion and reducing harmful exhaust emissions like carbon monoxide. California requires gasoline to contain oxygenates (typically ethanol) to reduce emissions.
California Certification Fuel
The California Air Resources Board developed a new certification fuel for 2015 and newer vehicles that closely resembles in-use fuel. The current certification fuel contains methyl tertiary-butyl ether (MTBE), which has been banned in California gasoline since December 31, 2003. The certification fuel for 2015 and newer vehicles contains 10 volume percent ethanol (E10) instead of MTBE.
Gasoline Deposit Control Additives
Any gasoline sold for on-road use in California must be certified for deposit control additives, as promulgated in California Code of Regulations, Title 13, Section 2257. To certify a gasoline formulation, the gasoline marketer must submit a written application to the Air Resources Board (CARB). The application must describe the additive formulation, specify the minimum dosage rate, and include test data showing that the formulation passes testing required to demonstrate engine cleanliness for port fuel injectors, intake valves, and combustion chambers.
Joint Statement on Gasoline Produced from Renewable Blendstocks
This is a joint statement by the California Air Resources Board (CARB) and the State Water Resources Control Board (State Water Board) intended to clarify questions that have been raised regarding gasoline made from renewable blendstocks.
Gasoline Frequently Asked Questions
| Title | Description | Date Published |
|---|---|---|
| Variances from California Gasoline Specifications Frequently Asked Questions | Information about the variance process specified by California’s Reformulated Gasoline Regulations (Title 13, California Code of Regulations, Section 2271), and notes that Senate Bill (SB) 237 (Grayson, Statutes of 2025) added a new statutory process for the Governor to potentially suspend gasoline Reid Vapor Pressure (RVP) regulatory control periods if certain conditions are met. | March 26, 2026 |
| AB 30 Frequently Asked Questions | Document designed to support implementation of Assembly Bill (AB) 30 (Alvarez, Chapter 247, Statutes of 2025) and California’s Reformulated Gasoline Regulations (Title 13, California Code of Regulations, Sections 2250-2273.5). As authorized by AB 30, at this time blends of gasoline containing 10.5% to 15% ethanol by volume (E15) that meet all applicable Federal, State, and local requirements may now be legally sold for use as a transportation fuel in California. | November 10, 2025 |
| Gasoline Frequently Asked Questions | General information about the Gasoline program. | Revised February 20, 2025 |
Gasoline Regulatory Advisories