(1) All weights, measures and weighing and measuring instruments used for purposes of trade and in the fields specified in section 20(2) shall be subject to pattern approval by the Director in accordance with the specifications and limits of error, as may be prescribed.
(2) The fee to be charged for any such pattern examination and approval shall be as prescribed.
(3) Where a subsequent examination of any weight, measure or weighing or measuring instrument which has been approved earlier by the Director is found to be defective, the Director may cancel such earlier approval and notify any person of such cancellation.