Gas Station Inspections

In Arizona, approximately 2 billion gallons of gasoline are pumped every year.

Are you getting what you pay for?

What We Do

The Division is responsible for regulating the proper measurement (fuel volume), vapor recovery and quality of motor fuels. Field officers examine fueling dispensers at each service station in Arizona approximately once every four years, unless there is a complaint.

How We Protect You

Check fuel volume: Officers pump fuel into a certified test measure (a container certified to deliver a known quantity) to check for the accuracy of the amount of product delivered by the dispenser.

Tell you if the dispenser is compliant: Officers place an approval seal (sticker) on the dispenser, if the dispenser passes the inspection and meets all legal requirements. If the dispenser does not pass the test, the Division will take enforcement actions to ensure the dispenser is repaired and recalibrated before it can be put back into service.

Check the fuel quality and octane rating: Officers take samples of fuel, which are analyzed by a contracted lab to ensure state and national legal requirements are met.

Investigate consumer complaints: We value consumer input by giving your questions and complaints a high priority. Consumers who register a complaint will be notified of any inspection results related to the complaint. Before calling in a complaint, see the complaint form to make sure you have all the information we will need to initiate a complaint inspection.

Require service stations to maintain their equipment. The outcome of our inspection is to ensure all devices are accurate and correct.

Note: The division does not regulate gas prices!

What You Can Do

Many factors draw motorists to a gas station, and price is near the top of the list. To be sure you are charged the correct amount, try the following "Times 10 Rule":

When pumping gas, make sure that you are being charged the correct price for each gallon you pump. When filling your gas tank:

Stop the flow of gasoline at exactly 10 gallons.

Move the decimal point of the total price (total price you pay shown on the meter display) one place to the left or move the decimal point of the price per gallon one place to the right or multiply by 10.

Remember the total price should be the same as the per gallon price.

Example: 10 gallons at $2.00 per gallon = $20.00

Don't Top Off

Gas nozzles are equipped with an automatic shut off valve. When you are filling your tank and the automatic shut off activates, it means your tank is full. When you continue to pump gas after the automatic shut off activates, the extra gas you try to put into your tank may actually be returning to the gas station's underground storage tank and NOT in your vehicle. Topping off your tank can also block the vapor return line, which may create problems for the next customer.

Vehicle Fuel Capacity

Keep in mind that the gasoline tank capacity, stated in the vehicle owner's manual, is ONLY an estimate. Your gas tank may hold more or less than the stated capacity.

Credit Card Purchase

Make sure you have been charged the correct amount and take your receipt with you.


Why can I put 20 gallons of gasoline in my tank when my vehicle owner's manual tells me I have a 19-gallon tank?
The manufacturer is quoting an estimated size of your tank. Your gas tank may hold more or less than what is stated in the owner's manual. Other factors that may have an impact include slope of the ground, when the auto shutoff valve activates and/or the accuracy of your gas gauge.

Does the Division control the price of gasoline?
No, we only regulate the posting of the price.

Does a gas station that has Diesel fuel have to list the price and then give back the $.08 in tax credit to all exempt vehicles?
The Arizona Department of Transportation requires service stations to refund the $.08 of the $.26 road tax for all exempt vehicles. If a station sells to both use and exempt class vehicles, the $.08 road tax must be included in the price posted at the pump.

Why do some gas pumps keep shutting off when I am pumping gas?
Gas nozzles are equipped with an automatic shut off valve. When you are filling your tank and the auto shut off activates, it means your tank is full. If the customer before you topped off his tank, the extra fuel he tried to add may have blocked the vapor return line, which would limit the dispenser's ability to pump fuel.

Are gas pumps in Arizona Required to have approval seals from the Weights and Measures Services Division?
No, but they are required to be licensed unless the station is on a military installation or is on a Native American Reservation and owned by a tribal member.

What do I do if I am getting ready to fill my tank and the "Total Sale" price on the dispenser indicates $.03 before I turn the dispenser on?
Ask the station attendant to reset the dispenser to zero. If the attendant won't reset the dispenser, report the incident to the Division. Remember to provide the address and pump number.

I prepaid for gasoline and the pump went really slow when it got close to the total Dollar amount. Did I get shorted on the amount of gasoline I paid for?
The dispenser is designed to slow down when nearing its preset sale amount.

Sometimes when I am filling my tank, the pump goes really slow. Why?
The cause could be the dispenser has a clogged filter.

On the dispenser it states "Do Not Top Off Tank After It Automatically Shuts Off." What does "Topping Off" mean?
Topping off means continuing to dispense more gas after the auto shut off has engaged. The nozzle is designed to shut off when your tank is full. In Maricopa County, if you top off, the gasoline you think you are getting could actually be returning to the station's storage tank due to the vapor recovery equipment. Outside the vapor recovery area, the gas could overflow from your tank, resulting in danger, including fire.

Why are some Diesel nozzles and regular gasoline nozzles the same color (green)?
Nozzle color is not regulated so station owners can install any color. Always check the dispenser label before you start fueling.

Should I fill up my tank when the tanker truck is delivering fuel?
This is not a good time to fill your tank because when filling the storage tank, material inside the storage tank can loosen and mix with the gasoline. You may be taking a chance of getting some of this material in your car's fueling system.

What is Arizona cleaner burning gasoline (AZCBG) and why do we have to use it?
The United States Environmental Protection Agency classified Phoenix Metropolitan area as a serious non-attainment area (did not meet federal regulations for clean air). Since the greatest contributors to poor air quality are motor vehicles, vehicles and their fuel were targeted as a major component in a plan to clean our air. Arizona CBG refers to the fuel specifications required in Maricopa County. This special fuel contributes to the reduction in harmful emissions.

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