Wastes from the following shall not discharge directly into any building
drain, soil or waste pipes: a refrigerator, icebox, soda fountain, bar waste,
fish or meat counters or other receptacle, appliance, device or apparatus
which is used for storage, preparation or processing of food or drink and
which is not water-connected; an appliance, device or apparatus using water
as a cooling or heating medium; a water still; a swimming pool; a water treatment
device or a water-operated device.
Drinking fountains may be installed with indirect wastes or shall be
connected directly into a drainage system trapped and vented same as other
fixtures. Such pipe shall have a minimum diameter of 1 1/4 inches.
Fixtures connected to indirect wastes shall be trapped, but it shall
be unnecessary to vent such fixture. The piping shall be installed with cleanouts
on horizontal runs.
Indirect waste pipes shall be installed in accordance with the provisions
of the other sections of this chapter applicable to sanitary drainage piping.
The diameter of refrigerator waste pipes shall not be less than 1 1/2
inches in diameter. Such pipes shall be of brass, copper or galvanized wrought
iron.
Indirect waste pipes shall discharge into a water-supplied, trapped
and vented open sink or other approved receptacle which shall be located in
an accessible, ventilated place. The air gap shall be equal to or greater
than the nominal diameter of the waste pipe.
Water lifts, expansion tanks, cooling jackets, sprinkler systems, drips
or overflow pans, or similar devices which waste clear water only, may discharge
onto a roof, into a sump or so as to drain into a trapped fixture.
Indirect waste pipes receiving the discharge from drinking fountains
or refrigerators on three or more floors shall be vented through the roof.
No toxic, corrosive, inflammable, explosive or other liquid, vapor,
gas or substance of any kind harmful to the drainage system shall be discharged
into such drain or sewer unless subjected to treatment approved by the administrative
authority.
Acid or alkaline wastes harmful to the normal drainage piping materials
shall be neutralized or otherwise rendered harmless before discharge to the
drainage system.
Appliances, devices or apparatus not regularly classed as plumbing fixtures,
but which have drips or drainage outlets, shall be drained by special waste
pipes discharging into an open fixture or other approved receptacle.