SHORT MEASURE1 IN EXCESS OF TOLERANCE2
Device short measured in excess of the allowed tolerance. Consumers using this pump would not get all the fuel indicated on the device display.
Device was not continuously maintained in proper operating condition to the extent that the accuracy of the pump could be affected. If more than 60% of the pumps at a station are found to short measure in any amount in the favor of the owner, the pumps are improperly maintained.
DOES NOT HOLD ZERO
Device did not begin transaction at $0.00 and 0.000 gallons.
TWO TIMES THE TOLERANCE2
Device delivered less fuel than the amount indicated on the device display by more than twice the allowed tolerance. Consumers using this pump would not get all the fuel indicated on the device display.
Device delivered less fuel than the amount indicated on the device display.
2TOLERANCE - The amount by which a device is allowed to deviate from zero discrepancy between the amount actually dispensed and the amount shown as having been dispensed on the device display.
The allowed tolerance for diesel and gas pumps in the maintenance phase is plus or minus six cubic inches, or approximately six tablespoons, when a 5-gallon test measure is used. Although a 5-gallon measure is the most common prover size used when testing diesel and gasoline pumps, other prover sizes, with different tolerances, occasionally may be used and some automotive fuel dispensing devices that dispense fuel at a higher rates require larger measures. The results of testing for high dispensing rate devices are not included within this report. The applicable tolerance for all newly installed devices is one-half the tolerance used during the maintenance phase. This report does not distinguish between devices tested during the installation phase and the maintenance phase and at this time, TDA cannot separate installation phase test results from the report.
Note: Whenever equipment is adjusted, the adjustments shall be so made as to bring performance errors as close as practicable to zero value. (NIST HB 44, G-UR.4.3)