Gas pumps in Michigan are certified by the Weights and Measures Program within the Michigan Department of Agriculture and Rural Development (MDARD), which operates under the Weights and Measures Act (Act 283 of 1964). MDARD inspectors test fuel dispensers in the field, condemn equipment that falls outside tolerance, and authorize pumps for commercial use.1Michigan Department of Agriculture and Rural Development. Routine Meter Maintenance Registered service persons, who are formally registered with MDARD, share part of that authority: they can place a repaired or newly installed dispenser back into service without waiting for a state inspector.
What MDARD Inspectors Check
The MDARD director has broad statutory authority to inspect and test any measuring device used commercially, investigate complaints, and issue stop-use, stop-removal, and removal orders. The same authority covers approving, rejecting, confiscating, or condemning equipment.2Justia Law. Michigan Act 283 of 1964 – Weights and Measures Act In practice, inspectors check calibration accuracy, mechanical condition, and whether the volume delivered matches the volume shown on the display.
The tolerance for a typical retail gasoline dispenser is plus or minus 6 cubic inches per delivery. Michigan’s standards track NIST Handbook 44, the national reference for commercial measuring devices. For retail motor-fuel dispensers in the 0.5 accuracy class, the maintenance tolerance is 0.5 percent of the delivered quantity; acceptance tolerance for newly installed or recently calibrated equipment is tighter at 0.3 percent.3National Institute of Standards and Technology. NIST Handbook 44-2026 – Specifications, Tolerances and Other Technical Requirements for Weighing and Measuring Devices
MDARD also looks at patterns across a station, not just individual pumps. When more than half of the dispensers at a station, or more than half of a single grade, are delivering less fuel than the display shows, the station is treated as “predominantly negative.” That pattern triggers enforcement even if each individual pump technically falls within tolerance, because it signals that equipment is not being properly maintained.1Michigan Department of Agriculture and Rural Development. Routine Meter Maintenance
Registered Service Persons
A registered service person is someone formally registered with MDARD to calibrate and repair commercial measuring devices. Their authority matters because of what it unlocks for a station: after a dispenser is condemned or newly installed, a registered service person can legally place it back into service as soon as repairs are complete. Without one, the station has to wait for an MDARD inspector to re-test and approve the equipment before any sales can resume from that pump.1Michigan Department of Agriculture and Rural Development. Routine Meter Maintenance
In other words, certification in Michigan runs through two channels. MDARD’s own inspectors conduct audits, respond to complaints, and act on failures. Registered service persons handle the day-to-day return-to-service work that keeps pumps legally operating between state visits.
When a Pump Fails Inspection
If a dispenser falls outside the allowable tolerance during a complaint investigation or field audit, MDARD condemns the device for repair or removes it from service entirely. A condemned pump cannot legally be used to sell fuel until the problem is corrected and the equipment is returned to service by either a state inspector or a registered service person.1Michigan Department of Agriculture and Rural Development. Routine Meter Maintenance
Enforcement can go further than condemning equipment. MDARD may assess the economic benefit a retailer received during the period of the violations, which can run from hundreds of dollars to tens of thousands depending on how long the short-measuring continued. Investigation costs may also be assessed against the violator, and the Weights and Measures Act carries criminal penalties that reach up to $20,000 per violation for the most serious offenses.1Michigan Department of Agriculture and Rural Development. Routine Meter Maintenance
Reporting a Suspect Pump
If you think a pump is delivering less fuel than its display shows, you can call MDARD directly at 800-632-3835 (800-MDA-FUEL). That number is required to be posted on pumps at every filling station in Michigan, so a complaint can be made on the spot.4Michigan Department of Agriculture and Rural Development. Contact MDARD – File a Complaint
When MDARD receives a complaint about a specific station, inspectors can conduct an unannounced investigation that includes re-testing the dispenser in question. If the pump is confirmed to be out of tolerance, it is condemned for repair. Price gouging is a separate matter and is handled by the Michigan Attorney General’s office at 877-765-8388, not by MDARD.4Michigan Department of Agriculture and Rural Development. Contact MDARD – File a Complaint
Certification Is Separate From Licensing and Fuel Quality
Pump certification is one of three MDARD responsibilities a station has to meet, and they are easy to confuse. Device accuracy sits under the Weights and Measures Act. Selling fuel at retail at all requires a separate Retail Motor Fuel Outlet License tied to each address, which is free but must be renewed on MDARD’s annual cycle.5Michigan Department of Agriculture and Rural Development. Retail Motor Fuel Outlet License The chemical quality of the fuel itself falls under the Motor Fuel Quality Act (Act 44 of 1984), which adopts ASTM International specifications and sets labeling, meter accuracy, and recordkeeping requirements for dispensers.6Michigan Legislature. Motor Fuels Quality Act – Act 44 of 1984 A pump that passes inspection on volume can still create problems for an operator if the license has lapsed or the fuel itself is off-spec.