New internationally adopted reference standards of voltage and resistance based on the Josephson and quantum Hall effects

By international agreement, starting on January 1, 1990, new reference standards of voltage and resistance based on the Josephson and quantum Hall effects, respectively, are to come into effect worldwide. Implementation of the new standards in the US requires that the value of the present national representation of the volt and ohm maintained at the National Institute of Standards and Technology (NIST) be increased by 9.264 and 1.69 parts per million (ppm), respectively. These changes are sufficiently large that literally thousands of electrical standards, measuring instruments, and electronic systems throughout the US will have to be adjusted in order to conform with the new US volt and ohm representation.<>