Harry Russell, age 13, of Middletown, Ohio, for his question:
WHEN WAS PLUMBING FIRST USED?
"Plumbing" is a word derived from "plumbum," a Latin word for the metallic element lead, the material most often used for piping until it was superseded by cast iron in the 19th century. Archeologists tell us that evidence of plumbing systems for the disposal of human waste has been found in dwellings 10,000 years old.
Waste disposal and running water were commonly incorporated in the palaces of royalty and priests from the time of the Indus Valley civilization through the Minoan civilization and these systems were well developed during the Roman Empire.
Then, after a long decline and a slow recovery, plumbing was a firmly established feature in dwellings of even the less affluent by the end of the 19th century.
To protect public health today, every inhabited building must have a supply of safe water for drinking and for the operation of the plumbing fixtures and appliances therein, and a sanitary drainage system for waste water disposal.
To provide the sanitary facilities required, local government authorities are responsible for establishing regulations known as plumbing codes, which specify design and installation requirements and the minimum number of fixtures needed, based on building use.
Today basic modern plumbing fixtures include water closets, urinals, lavatories, sinks, bathtubs, showers, laundry tubs, drinking fountains, dishwashers and laundry washers.
Fixtures today are made of impervious materials such as vitreous china, enameled cast iron or steel, stainless steel and plastic. Piping materials in common use include cast iron, steel, brass, copper, stainless steel, aluminum, plastic, vitrified clay (tile) and concrete.
In developed communities, water under pressure is secure from water mains and piped into the buildings to all fixtures requiring it. In other areas, water must be obtained from on site wells or adjacent streams or lakes. Care must be taken to assure water quality.
Drainage systems are of two basic types: sanitary and storm water.
Sanitary drainage systems carry body and other wastes from the plumbing fixtures and appliances by gravity to a sewer or sewage treatment facility. Sanitary drainage piping inside the building must be provided with a companion system of vent piping, extending through the roof to keep the pressures in the drainage piping minimal and equalized in order to prevent the siphoning or blowing of water in the traps, which would allow sewer gas to enter the building. Traps, by the way, are the U shaped dips in piping.
Domestic storm water drainage systems carry rainwater from the roof by gravity to a sewer or dry well.
Hospitals and laboratories often require additional special drainage systems for removal of acid waste and infectious waste drainage systems.
Both water supply and drainage systems must be carefully designed to prevent serious contamination of the water and to stop sewer gas from entering the building.