California Air Resources Board

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.