(3)It shall be open to municipalities to introduce such modification, addition or alteration in the Building Bye-law, framed by the State Government consistent with specific requirement of such Municipalities:Provided that any such modification, addition or alteration in the Bye-law introduced by the Municipality shall not be enforceable unless it is approved by the State Government:Provided further that if State Government does not communicate its decision within 90 days from receipt of modified Bye-law from the Municipality, on expiry of 90 days, it shall be deemed to have been approved by the State Government.