(a)a person under 18 year of age and women shall not be employed in any process in which hydrofluoric acid fumes or ammoniacal vapors are given off or in any of the following operations.(i)evaporation of brine in open pans;(ii)stoving of salt(iii)work at furnace where the treatment of zinc ores is carried on ; and(iv)the cleaning of work-rooms where the process mentioned in (iii) is carried on .
