John Worth, Superintendent
(609) 989-6875
Mercer County Office of Weights and Measures is responsible for consumer protection by making sure everything from gasoline pumps to supermarket scales are calibrated properly and charge customers accurately.

Our Weights and Measures professionals are working for County residents all throughout the year to ensure that Mercer County residents are getting exactly what they deserve---the most value for their dollar.

The office inspects a wide variety of measuring devices and products and can order businesses to correct or repair anything found to be inaccurate. Fines can be issued if problems are not rectified.

Examples of common inspections that may not be known to the public are on products such as home heating oil and cords of firewood; lengths of carpet, rope, and fabric; measuring devices like scales at pharmacies, jewelry stores, delis, and grocery stores; gas pumps; timed devices like Laundromat dryers and vacuum and air stations at gas stations and car washes; and signage, prices, octane levels, and water levels at gas stations.

The County Weights and Measures Office has some of the most sophisticated equipment in the State to conduct tests. Its' new computerized system, called WINWAM (Windows for Weights and Measures), is the most efficient and accurate method of calculating and recording measurements. The WINWAM system keeps a record of all measurements, making it easy to identify problem devices or search a business' inspection history. In addition, the system has a log of all devices required to be registered by the State of New Jersey and can alert the Weights and Measures office when an inspection is due. WINWAM also makes complicated calculations instantly and eliminates human error.

The office also uses a specialized truck fitted with 3 individual test measures, one for each grade of gasoline when testing meters for volumetric accuracy. The size of the test measure or "prover" is based on the flow rate of the meter. Fast-flow diesel used to fill larger tractor trailers use a fifty gallon prover and for home heating oil delivery trucks a 200 gallon prover is used. Officials inspect for updated inspection stickers, pricing accuracy, signage and state required documentation. Inspectors can perform an on the spot analysis of octane, using a portable octane analyzer, a test not required and is the only Weights & Measures office in Mercer County that owns this type of testing device.

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"The equipment we have really enables us to be a watchdog by doing much more testing in more places. Our inspections make Mercer County one of the most transparent markets for consumers, and we see the businesses as partners with our office. We work hand-in-hand all year long."

- John Worth, Superintendent of the County Weights and Measures Office
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