New international representations of the volt and ohm effective January 1, 1990

Starting January 1, 1990, new representations of the volt and ohm based on the Josephson and quantum Hall effects, respectively, are to come into effect worldwide. Their implementation in the US will result in increases in the values of the national representation of the volt and ohm maintained at the National Institute of Standards and Technology (NIST) of 9.264 parts per million (p.p.m.) and 1.69 p.p.m., respectively. The resulting increases in the values of the US representation of the ampere and US electrical representation of the watt will be 7.57 p.p.m. and 16.84 p.p.m., respectively. The reporting of calibration results in terms of the new representations is discussed.<
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