Section 6(a) in The Chennai Metropolitan Water Supply and Sewerage Board's Sewerage Regulations, 1988
(a)On receipt of approval, all internal sewer, soil and water pipes and fitting up to the terminal chamber of the premises shall be laid by a plumber licensed by the Board, under the supervision of authorised authority of the Board. The authorised authority after having satisfied himself that the works had been carried out in conformity with the regulations and as per approval shall issue a certificate free of charge that the pipes and fitting have been laid and executed in a satisfactory manner in conformity with the sewerage regulations.
