In multiple tenant buildings, where a common piping system is installed to supply other than individual dwelling units, shutoff valves shall be provided for each tenant. Each tenant shall have access to the shutoff valve serving that tenant's space.
In a common system serving more than one building, shutoff valves shall be installed outdoors at each building.
Each house line shutoff valve shall be plainly marked with an identification tag attached by the installer so that the piping systems supplied by such valves are readily identified.