You asked about state and federal laws to ensure the accuracy of gasoline pumps and the Department of Consumer Protection's Pump inspection process.

The Department of Consumer Protection (DCP) commissioner is the state's weights and measures commissioner. As such he has general supervision of weights and measures standards and weighing and measuring devices used in the state. He, or inspectors he appoints, is empowered to inspect such devices to ensure their accuracy (CGS § 43-3).  But the law requires the chief executive officer in towns with populations of 75,000 or more to appoint a municipal sealer of weights and measures who is responsible for inspections in those towns. If a town does not appoint a municipal sealer, DCP can perform the inspections (CGS § 43-6).

DCP's Food and Standards Division is responsible for the inspections (except in towns with a municipal sealer). Its inspectors strive to examine each pump once a year, according to Division Chief Frank Greene. They also inspect in response to complaints. Inspections encompass both the pump's accuracy in measuring and pricing and the accuracy of the octane rating of the gasoline dispensed.

Inspectors follow DCP procedural guidelines that are based on NIST standards (Handbook 44, Section 1.6.5,

http://ts.nist.gov/WeightsAndMeasures/Publications/upload/3-30-09-HB44-FINAL.pdf). In assessing a pump's accuracy, inspectors use calibrated five-gallon measuring devices called “proovers.” The proovers' accuracy is certified by a laboratory that is, in turn, certified by the National Institute of Standards and Technology (NIST). Inspectors test pumps at “fast” and “slow” dispensing rates. They check each pump's money computation by setting the selector control for each blend and dispensing one indicated gallon to check the computed price. NIST standards permit slight allowances (up to 5 cents) on older pumps, depending on the unit price of the gas.

A person who uses a false measuring device in selling a commodity knowingly sells or offers for sale less than the quantity represented, or offers or sells a commodity in any way that violates the weights and measures law is subject to criminal penalties. For a first conviction the person can be fined between $50 and $300, be imprisoned for up to three months, or both; for any subsequent conviction the person is subject to a $300 to $1,000 fine, one year in prison, or both. The DCP commissioner can, after a hearing, also impose a civil fine on anyone who violates these laws or implementing regulations. The fine is up to $100 for a first offense and up to $500 for any subsequent offense. Each time a device is used in violation is a separate offense (CGS § 43-9).

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