Section 68(1)(b) in The Trade And Merchandise Marks Act, 1958
(b)the us of a certification trade mark in relation to goods certified by the proprietor of the mark if, as to those goods or a bulk of which they form part, the proprietor or another in accordance with his authorisation under the relevant regulations has applied the mark and has not subsequently removed or obliterated it, or the proprietor has at any time expressly or impliedly consented to the muse of the mark;