This standard, Test 4 of a series of five washing tests, prescribes a method for determination of colour fastness of textile materials irrespective of their composition ( cotton, linen, man-made fibres, etc ) and their form ( fibre, yarn or fabric) to the action of soap and sodium carbonate solution at 95°C along with beating action of steel balls. It is applicable only to those fibres which are capable of withstanding such conditions.
IS 765-1979 history
1979IS 765-1979 Method for determination of color fastness to washing of textile materials: Test 4