law: The Legal Metrology Act, 2009
  6. Base unit of
  
  numeration. -
  1.  The
  
  base unit of numeration shall be the unit of the international form of Indian
  
  numerals.
  2.  Every
  
  numeration shall be made in accordance with the decimal system.
  3.  The
  
  decimal multiples and sub-multiples of the numerals shall be of such
  
  denominations and be written in such manner as may be prescribed.