Schedule 3: amended, on 1 April 1974, by section 56(1) of the Clean Air Act 1972 (1972 No 31).
Schedule 3: amended, on 25 October 1960, by section 5(1) of the Health Amendment Act 1960 (1960 No 96).
Schedule 3: amended, on 1 June 1959, by clause 2 of the Offensive Trades Order 1959 (SR 1959/79).