I don't know about US, but this does need formal amendment to Weights and Measures Act 1985 (current UK standard in force) Schedule 1 Part V, see http://www.leg

I don't know about US, but this does need formal amendment to Weights and Measures Act 1985 (current UK standard in force) Schedule 1 Part V, see http://www.legislation.gov.uk/ukpga/1985/72/schedule/1/part/V http://www.legislation.gov.uk/ukpga/1985/72/schedule/1/part/....