Cleaner-Burning Gasoline

Air and Fuel Quality

The Division Fuel Quality program administers the laws and regulations for fuel quality through inspection, analysis and enforcement to help ensure consumers are purchasing quality transportation fuels and to protect air quality. Fuel samples are first tested in the field by investigators and potentially non-compliant fuel is collected for testing at a state of the art laboratory which has the latest analytical equipment and techniques to provide precise results. Additionally, samples are collected for laboratory analysis during randomly scheduled unannounced inspections and when complaints regarding fuel quality are received by the Division.  The Division will follow up with laboratory analysis of gasoline, diesel fuels, high octane racing fuels and biofuels, including biodiesel and E85 fuel ethanol, to make certain they meet state quality and safety standards.


View a List of Registered Suppliers (CBG)


What We Do


The Division audits the refineries to verify compliance with regulatory reporting requirements, analytical methodology and procedures used to analyze fuel quality. This helps the Division to ensure that the fuel being produced at the refineries meets both the regulatory and fuel quality requirements before it leaves the refineries. It is at this point the refineries certify the fuel as CBG.  

Storage Terminal

This is an intermediate point where different batches come together before it is put into the pipeline. This is the point where the fuel becomes a fungible product (it loses its individual identify when it is mixed with other batches of CBG). The Division requires that the transfer of this fuel be tracked to ensure that the fuel is not mixed with anything other than the required CBG ingredients.


The Division requires that the fuel parameters be checked prior to entering the pipeline to ensure it meets federal and state requirements. A Quality Assurance program is also required to randomly check different suppliers fuel quality parameters. These parameters are then reported to the Division.  The Division maintains monthly oversight of this Quality Assurance program and the proprietary information and ensures requirements are regularly maintained, while communicating Arizona’s concerns on a regular basis.

Distribution Terminal

After the long journey to the Phoenix or Tucson terminal the fuel is now ready to be distributed to the service stations in the area. Before delivery, the fuel must first be blended with up to 10% Ethanol which is done just as the fuel is loaded into the truck that will deliver it.  The Division requires the terminal to have a Quality Assurance program not unlike that of the pipeline. The terminal is required to take random samples from trucks at the loading rack to help insure that the level of ethanol will meet State requirements.  Every inspection for fuel quality conducted by Division investigators incorporates a thorough analysis of the Product Transfer Documents (“PTD”) which spell out the exact fuel content and specifications, as well as the destination and other chain of custody requirements.  Investigators regularly review these PTDs as maintained by transportation fueling trucks and inside each gas station.

Fueling Stations

The last point at which the Division can ensure fuel quality is at the service stations.   On a daily basis, Division investigators randomly visit service stations collecting samples, checking equipment and conducting a number of other tests. As mentioned, the samples collected are taken to a laboratory to be analyzed.

Business Specifics

State law requires you to be a registered supplier and to follow specific laws and administrative rules relating to Arizona Cleaner Burning Gas (CBG) or Arizona Reformulated Blend Stock for Oxygenated Blending (AZRBOB) program. Here are some pages that may be of interest to you.

Compliance Assistance Program

Division is making every effort to assist the fuel industry in achieving compliance with Arizona fuel regulations. Here you will find important documents and guidance related to the Arizona fuels program. These documents are available in the table below organized by date of release. However, each document may cover numerous topics, and different facets of a topic may be discussed in more than one document. In "More Information" you will find links to other pertinent documents from both CARB and EPA. These documents do not establish or change legal rights or obligations. Since their release, however, some of the responses have been incorporated into the regulations.

The California Predictive Model (MS Excel) spreadsheet contains the predictive model procedures and calculations for the CARB Phase 2 PM alternative formulations for gasoline. Note: The point of compliance is the actual procedural document and not this spreadsheet.

Emmissions Models

Modification of this spreadsheet could result in non-compliance specifications being generated. This spreadsheet is meant to only assist you. The use of this spreadsheet does not automatically assure compliance with the requirement in AAC R3-7-751(E).

EPA Complex Model to be used to certify Type 1 gasoline meets the emission reductions in R3-7-751 and Table 1.


California Procedure for Evaluating Alternative Specifications for Phase 2 Reformulated Gasoline Download
Arizona Department of Weights and Measures Quality Assurance /Quality Control Plan Policy Development Download
Statement of Interpretation R20-2-753 (A)(2); R20-2-753(C),(E), and (F) Download
Audit Protocol for the Arizona Department of Weights and Measures Motor Fuels and Petroleum Products Arizona CBG and AZRBOB Download
Audit Guidelines for the Arizona Department of Weights and Measures Quality Audits of Registered Supplier and Independent Laboratories Download
Letter from Director Macias regarding the Blending of Gasoline with Ethanol Download
Acceptance Criteria for Approval of Biofuels QA/QC Plans Download
Compliance Advisory - Octane Levels of Blended Gasoline Download

Want More Information?

Contact Kevin Allen, Vapor and Fuel Compliance Manager, at [email protected] or 602-771-4939.

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