=Bath Tubs.=--Bath tubs are made of enameled iron or porcelain, and should not be covered or inclosed by any woodwork. The branch waste pipe should be trapped and connected with the main waste or soil pipe. The floor about the tub in the bathroom should be of nonabsorbent material.[19]
=Refrigerators.=--The waste pipes of refrigerators should not connect with any of the house pipes, but should be emptied into a basin or pail; or, if the refrigerator is large, its waste pipe should be conducted to the cellar, where it should discharge into a properly trapped, sewer-connected and water-supplied open sink.
=Boilers.=--The so-called sediment pipe from the hot-water boiler in the kitchen should be connected with the sink trap at the inlet side of the trap.
=Urinals.=--As a rule, no urinals should be tolerated within a house; they are permissible only in factories and office buildings. The material is enameled iron or porcelain. They must be provided with a proper water supply to flush them.
=Overflows.=--To guard against overflow of washbasins, bath tubs, etc., overflow pipes from the upper portion of the fixtures are commonly provided. These pipes are connected with the inlet side of the trap of the same fixture. They are, however, liable to become a nuisance by being obstructed with dirt and not being constantly flushed; whenever possible they should be dispensed with.
=Safes and Wastes.=--A common usage with plumbers in the past has been to provide sinks, washbasins, bath tubs, and water-closets, not only with overflow pipes, but also with so-called safes, which consist of sheets of lead turned up several inches at the edge so as to catch all drippings and overflow from fixtures; from these safes a drip pipe or waste is conducted to the cellar, where it empties into a sink. Of course, when such safe wastes are connected with the soil or waste pipes, they become a source of danger, even if they are trapped, as they are not properly cared for or flushed; and their traps are usually not sealed. Even when discharging into a sink in the cellar, safes and safe waste are very unsightly, dirty, liable to accumulate filth, and are offensive. With open plumbing, and with the floors under the fixtures of nonabsorbent material, they are useless.