Fuel Station Inspections

What We Do

The Weights and Measures Services Division (WMSD) regulates approximately 2,000 retail fuel dispensing sites across Arizona. WMSD investigators conduct a variety of inspections at these locations to ensure that:

  • Motor fuel dispensers are accurate and properly maintained
  • Motor fuels sold meet applicable quality specifications
  • Gasoline vapor recovery systems (Phoenix Metro area only) are leak-tight and meet certain design specifications
  • Credit card skimming devices are not attached to motor fuel dispensers

Retail motor fuel dispensing site inspections include fuel quality screening and/or analysis, and may also include price posting and price accuracy inspections of the convenience store (if present). Gasoline vapor recovery inspections are conducted annually in the Phoenix Metro area, and WMSD investigators inspect for credit card skimming devices whenever they perform any fuel-related inspection at a dispensing site. WMSD also responds to consumer complaints within the following timeframes:

  • Within ten days (fueling device complaints)
  • Within 24 hours (fuel quality and skimmer complaints)*

*Response time may be delayed if a complaint is received immediately before or during a weekend or government holiday. 

How We Protect You 

Volumetric Test: Have you ever wondered if a fuel dispenser is delivering product accurately? WMSD investigators test accuracy by dispensing fuel into a certified prover or test measure (a special container calibrated to a known volume). For most fuel dispensers, volumetric tests are performed using a 5-gallon prover or test measure. For high-flow diesel dispensers, volumetric tests are performed using a trailer-mounted 100-gallon prover. WMSD even has special equipment to test the accuracy of Diesel Exhaust Fluid (DEF) dispensers.

Indicators and Labeling: WMSD investigators inspect all fuel dispensers to ensure that product, price, and tax information is correct, and clearly displayed to the consumer.

Fuel Quality: WMSD investigators screen and/or sample different motor fuel grades to compare against applicable fuel quality specifications for vehicle performance and emissions reduction.

Safety: WMSD investigators test the auto-shutoff, hold-open latch (if equipped), and anti-drain functions on fuel nozzles and also inspect all hanging hardware (hoses/nozzles) and internal piping (meters/shear valves) for leaks.


PLEASE NOTE: The division does not regulate fuel prices. Click here for more information about fuel prices.


Have a question? Try our Fueling FAQ's page. We also have pages specific to credit card skimmers, fuel quality, and gasoline vapor recovery. If you cannot find what you are looking for, you are always welcome to contact the Weights and Measures Services Division at 602-542-4373 or [email protected]



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