India will adopt a new definition of the kilogram (kg) from May next year, after representatives of 60 countries last week voted to redefine the International System of Units. The new SI System will be helpful in bringing in accuracy while dealing with international trade, biotechnology, high-tech manufacturing and human health and safety, said Consumer Affairs Secretary AK Srivastava during a press briefing here.
The existing definition of the kg is over 130 years old. The new SI system, which is defined in terms of the Planck’s constant, would be stable in the long term and practically realisable. The 26th General Conference on Weights & Measures (GCWM), which is comprised of 60 member countries, voted for the redefinition last week. It will be adopted on May 20, which is World Metrology Day.
The new definition of kg involves accurate weighing machines called ‘Kibble balance’. It uses the constant to measure the mass of an object using a precisely measured electromagnetic force. National Physical Laboratory (NPL) Director DK Aswal said the facility to produce ‘Kibble balance’ machines to be used across the country will be ready in the next three-four years. It is expected to cost Rs 60 crore.