Factories Act, 1948
41F. Permissible limits of exposure of chemical and toxic substances
(1) The maximum permissible threshold limits of exposure of chemical and toxic substances in manufacturing processes (whether hazardous or otherwise) in any factory shall be of the value indicated in the Second Schedule.
(2) The Central Government may, at any time, for the purpose of giving effect to any scientific proof obtained from specialized institutions or experts in the field, by notification in the Official Gazette, make changes in the said Schedule.