8.113. The installation of the following is prohibited:(1) aboveground outdoor piping on walls unless the walls are of non-combustible construction;
(2) outdoor piping above windows;
(3) outdoor piping above roofs, except roofs that are non-combustible and impermeable to petroleum products with provision for the collection of spillage to prevent a fire; and
(4) piping containing petroleum products in service tunnels used for pedestrian traffic other than tunnels reserved for maintenance personnel.