Safe and refrigerator waste pipes must be of
galvanized iron and not less than 1 1/4 inches in diameter, with
pipe branches at least one inch in diameter with strainers over each
inlet.
Safe and refrigerator pipes shall not be trapped.
They must discharge over a properly water-supplied trapped sink, with
trap vented unless permission is granted by the Superintendent of
Buildings to use an approved antisiphon trap. Such sink shall be publicly
placed and not more than four feet above the floor. In no case shall
any refrigerator or safe waste pipe discharge over a sink located
in a room used for living purposes.
The branches on vertical lines must be made
by Y- or TY-fittings and carried up to the safe with as much pitch
as possible.
Lead safes must be graded and neatly turned
over bevel strips at their edges.
Where there is an offset on a refrigerator waste
pipe in the cellar, there must be a cleanout to control the horizontal
part of the pipe.
In all lodgings and multiple dwellings, the
safe and refrigerator waste pipes must extend above the roof.
