Toilet

views updated May 09 2018

Toilet

Background

A system for dealing with excrement is necessary in every human community, and the need becomes more pressing the more densely populated the area. Though simple pit latrines are still common in many rural areas today, more complex lavatory designs date back thousands of years. The Old Testament contains several references to toilets, from laws about how to cover waste out of doors to mention of King Eglon of Moab's indoor privy chamber. Some kind of lavatory flushed with water is believed to have been used by residents of the Indus Valley by around 2000 b.c. Even earlier, in about 2750 b.c., the ancient Indian city of Mohendro Daro was equipped with toilets connected to a drain. Dating back to approximately 4000 b.c., the neolithic stone huts of the Scara Brae settlement in the Orkney Islands seem to have had indoor lavatory provisions. Apparently used as toilets, stone chairs have also been unearthed from the site of the Sumerian city of Ashnunnack, dating to around 4000 b.c. The palace of King Minos of Crete, from about 2000 b.c., had elaborate indoor plumbing, including marble toilets that were flushed with water dumped from a vase in an adjoining room.

The remains of Roman lavatories are still extant in many places. Some private Roman houses had their own toilets, which were in most cases a seat located over a drain or a cesspit. Roman public lavatories were more impressive. They were often built next to or as part of public baths. Rows of stone or marble seats in pairs, divided by armrests, stood over a trench. Excess water from the baths flowed into the trench, and washed the waste into a main sewer. A smaller trench filled with fresh water flowed past the base of the stone toilets. This water was used for rinsing. Roman forts, which housed hundreds of soldiers, also boasted impressive toilet facilities. The builders of Housesteads, a Roman fort in northern England dating to 122 a.d., diverted a river to flow underneath the latrine and carry waste out of the fort. The latrine itself was a large room with benches built around three walls. The benches had about 20 holes with no dividers for privacy. Roman cities also took care of the needs of travelers by erecting huge vases along the roadways for people to urinate into, thus keeping waste off the public streets.

During the Middle Ages, lavatories drained with running water were common in British abbeys, which housed large groups of monks. Similar to the Roman forts, abbey latrines were usually meant for many people to use at once, and drained over a river or stone drain. Stone castles were often designed with vertical shafts for the emptying of waste. The waste flowed into a trench leading in most cases to the moat. Indoor toilets consisted of wooden closets or cupboards, which concealed a seat over a chamber pot. Servants emptied the pot into the moat.

In Medieval European cities, common practice was to empty indoor chamber pots directly into the streets, a foul practice that bred disease. Something akin to the modern flushing toilet first came into use in England at the end of the sixteenth century. A water-operated "water closet" was invented in 1596 by Sir John Harrington. Queen Elizabeth I had Harrington's device installed in her palace, setting the vogue among the nobility. However, flushing toilets did not catch on with the bulk of the population until much later. The first British patent for a water closet was awarded to Alexander Cumming in 1775. His device used a pan with a sliding door. The pan contained a few inches of water. When finished, the user would pull a lever that opened the pan, letting the contents slide out into a drain, and at the same time opening a valve that let fresh water into the pan. The Bramah water closet, patented by Joseph Bramah in 1778, used a similar but more complex flushing device that kept the water running for about 15 seconds. By about 1815, water closets of this type had become common in London households. A modern sewer system was completed in London in 1853, and a large-scale toilet manufacturing industry dates to around this time.

Raw Materials

Toilet bowls and tanks are made from a special clay called vitreous china. Vitreous china is a mix of several kinds of clay, called ball clay and china clay, silica, and a fluxing agent. Clays are hardened by first drying in air, then being fired (baked) in a very hot oven called a kiln. Usually a shiny, waterproof coating called a glaze is applied only after a first firing, and the clay is fired a second time. Vitreous china is an exception, in that clay and glaze can be fired together. The whole clay body vitrifies, or turns glassy, so the toilet is actually waterproof and stainproof through its entire thickness.

Toilet seats are generally made from one of two materials. Plastic toilet seats are made from a type of thermoplastic called polystyrene. The less expensive and more common type of toilet seat is made from a blend of wood and plastic. The wood is hardwood, usually maple or birch, which has been ground up into the consistency of flour. This wood flour is blended with a powdered plastic resin called melamine. Zinc stearate is a third ingredient in wooden toilet seats. This prevents the wood-resin mix from sticking to the mold in the manufacturing process. The metal tank fixtures are made of stainless steel or copper, and the joints that hold the seat to the bowl are usually a rubber-like plastic.

Some Victorians couldn't abide the thought of indoor toilets because they reviled at the notion of odor and unclean gases associated with them. Today, it is difficult to imagine life without indoor plumbing. How awful to have to scurry to the outhouse in cold weather or to stumble to the privy late at night when duty called.

One did not always have to walk to the privy on these occasions, however. Instead, one could use a ceramic chamber pot. It functioned like an indoor toilet that did not flush—one perched upon it for defecation or used it as a urinal and then the "slop jar" was emptied into the outhouse. Some chamber pots were decorated with lacy covers along the edge of the bowl called silencers and presumably muffled the noise of clanking of the top upon the bowl at night so that others weren't awakened by its use.

The chamber pot in the photo is part of a large set of ceramics used for personal hygiene in the days before indoor plumbing. Many bedrooms had a pitcher for fresh water, a basin to hold the water for cleansing, a soap dish and a chamber pot. These ceramics were always fashionably decorated, so that the bedroom could be attractively appointed even for these disagreeable tasks.

The Manufacturing
Process

Plastic seat

  • 1 Plastic seats begin as pellets of polystyrene. A worker feeds the pellets into a hopper attached to an injection molding machine. From the hopper, a precisely measured amount of pellets flows into a container that heats the material until it melts. Then the liquid polystyrene flows through a small hole in the center of a two-part mold. The mold is made of chrome-plated machined die steel. Its two halves are hollowed in the shape of the toilet seat and cover. When the mold is full, it is clamped together by a huge hydraulic press. This exerts 10,000 lb per sq in (4,540 kg per sq cm) of pressure on the mold, and heats the polystyrene to 400° F (204° C).
  • 2 The plastic in the mold begins to solidify. Then cool water is pumped through a channel system around the mold to bring the temperature down. A worker releases the hydraulic clamp and separates the two halves of the mold. The worker removes the seat and cover from the mold, breaking off the extra plastic that formed in the water channel. Then, the worker places the seat and cover into a water bath.
  • 3 After the seat and cover have cooled in the bath, a worker takes them to a finishing area for the final steps. Here holes are drilled for the hinges. Then, a worker smooths the rough edges at a sanding machine. The sander is a rotating wheel covered with an abrasive material. The worker passes the seat or cover along the wheel until any plastic fragments from the drilling or from the mold are sanded off. A similar machine with a softer surface may next be used to give a final polish.

Wooden seat

  • 4 For wooden toilet seats, the first step is to mix the wood flour and the plastic resin. Workers wearing protective masks slit open bags of wood flour and empty them into a mix box. Then, the worker adds the powdered plastic resin that makes up 15% of the formula. Last, a small amount of zinc stearate is added. The mixture is passed to an attrition mill, which grinds the particles down further. After milling, the powdered mixture may be measured into boxes for loading into the molding press. Or it may be set aside, and later measured and scooped by hand into the press.
  • 5 The processed wood and melamine mixture is next emptied into the bottom half of a mold. A worker makes sure the mix fills the mold evenly and smooths the surface. Then the worker lowers the top half of the mold and begins to heat the whole thing to 300° F (149° C). While it heats, the mold is clamped at 150 tons of force. After 6.5 minutes, the wood flour and melamine have fused together and hardened. Then, the worker opens the mold and hangs the seat and cover on an overhead conveyor rack, which moves it along to the finishing area.
  • 6 Wooden seats are finished in the same way as plastic seats. First, they are drilled, then sanded. Then, they are hung again on an overhead conveyor and taken to the painting area. The conveyor automatically lowers the seats into a tank of paint. Then the conveyor pulls them up and passes them into an enclosed room called a vapor chamber. A paint solvent is released as a vapor, and this carries off any excess paint without leaving drip marks. Next, the painted seats pass along the conveyor into a drying oven. The paint-vapor-drying process is repeated four times. The first two coats are a primer, and the second two are an enamel paint that produces a smooth, hard, plastic-like surface.
  • 7 Both plastic and wooden seats are assembled and packaged the same way. The seats and covers are screwed together and packed with the necessary mounting hardware. Then, they are boxed and moved to a warehouse or distribution center.

Bowl and tank

  • 8 The toilet bowl and tank are made at a type of factory known as a pottery. The pottery receives huge amounts of vitreous china in a liquid form called slurry slip. Workers at the pottery first thin the slurry slip to a watery consistency. Then, they feed it through very fine screens in order to sieve out any impurities. The purified slip is thickened again, and pumped into storage tanks in preparation for use in casting.
  • 9 Next, the slip is carried through hoses and pumps into the casting shop. Workers fill plaster of Paris molds with the slip. The molds are in the shape of the desired piece, except they are about 12% bigger, to allow for shrinkage. The workers fill the molds completely with the slip, and let it sit for about an hour. Then, the workers drain out any excess slip. This is recycled for later use. The clay sits in the mold for another few hours. The plaster of Paris absorbs water from the clay, and the clay dries to the point where the mold can be safely removed. At this point, the casting is semisolid, and is called greenware. Workers use hand tools and sponges to smooth the edges of the casting and to make holes for drains and fittings.
  • 10 The greenware castings are left to dry in the open air for several days. Then they are put into a dryer for 20 hours. The dryer is set to 200° F (93° C). After the castings come out of the dryer, they have lost all but about 0.5% of their moisture. At this point workers spray the greenware castings with glaze. Now, the pieces are ready for the kiln.
  • 11 The kilns at a large industrial pottery are warehouse-sized tunnels, and the pieces move through the kiln on a conveyance called a car. Each car is loaded with a number of pieces, and then it moves automatically through the hot kiln at a very slow pace. Because rapid changes in temperature will cause the clay to crack, the cars move leisurely through graduated temperature zones: the first zone is about 400° F (204° C), and it increases in the middle of the kiln to over 2,200° F (1,204° C) degrees. The temperature gradually decreases from there, so that the final temperature is only about 200° F (93° C). The whole firing process takes approximately 40 hours.
  • 12 When the pieces are removed from the kiln and fully cool, they are ready for inspection. After inspection, the flushing mechanism is installed. This is either manufactured at the plumbing fixture company or bought from a contractor. The seat too may be installed at this time, or the parts may be sold separately and assembled by a plumbing distributor.

Quality Control

As with any industrial process, quality checks are taken at several points in the manufacturing of toilets. The clay is sieved and purified before it is pumped into the factory's tanks. Workers doing the manual finishing of the castings check the pieces for cracks or deformities. After firing, each toilet is tested individually. Random sample checks are not a good enough gauge of quality: each piece must be inspected for cracks. There are several ways to do this. One test is to bounce a hard rubber ball against the piece. It should emit a clear, bell-like ringing sound. A cracked piece will give off a dull sound, indicating a crack that might not have been visually obvious.

Byproducts/Waste

The pottery is able to recycle much of its clay. As long as it has not been fired, all the clay is reusable. Even the air-dried greenware can be scrapped, softened and reprocessed into the watery slip of the first step of the process.

Where to Learn More

Books

Barlow, Ronald S. The Vanishing American Outhouse. El Cajon, California: Windmill Publishing Company, 1989.

Hart-Davis, Adam. Thunder, Flush and Thomas Crapper. North Pomfret, Vermont: Trafalgar Square Publishing, 1997.

Reyburn, Wallace. Flushed with Pride: The Story of Thomas Crapper. Englewood Cliffs, New Jersey: Prentice-Hall, 1971.

AngelaWoodward

Toilets

views updated May 14 2018

Toilets

BIBLIOGRAPHY

This article is concerned with indoor conveniences: both domestic home toilets and those in the workplace and public buildings. Technological and cultural factors are discussed to understand why everyone, in the West at least, thinks it is quite normal to have a flushing toilet inside the house.

The Romans installed toilets inside their villas over 2000 years ago. But indoor plumbing was not a feature of European cities until the time of Queen Elizabeth I, for whom Sir John Harrington installed the first valve-flushing toilet in the 1590s. The majority of the population used chamber pots or relieved themselves outdoors. The wealthy had no need of domestic toilets; they had chambermaids. The few toilets that existed comprised a privy at the bottom of the garden, or on the outside of the castle wall hanging over the river. Privacy was not a major consideration, and men, especially, could relieve themselves anywhere inside or outside the house.

It was not until the Industrial Revolution that toilet provision became an issue. It was no longer acceptable to throw human waste on the midden outside the house. The ruling classes saw it in their own interests to enact public health reforms and to build sewers and drains because cholera is no respecter of class distinctions.

The introduction of water-based sewerage systems required the installation of flushing toilets. New paradigms of hygiene and social morality arose. The toilet had to be tamed and domesticated and brought inside the house from the yard. Toilet entrepreneurs such as Thomas Crapper in Britain, and John Randall Mann in North America, capitalized upon this new toilet market, for every home should have one. Design was based upon the sit rather than squat style of toilet provision and exported globally. Most people in the world still squat and have no access to modern toilets or toilet paper. To have a flush-toilet in your house is a sign of great wealth, with the increasing scarcity and privatization of water supply in developing countries.

Social prudery made it taboo directly to talk about bodily functions in polite company. Americans say they are going to the bathroom, (in a bathtubless room?), the British ask for the little room. In Far East countries bodily functions are not seen to be as culturally and religiously dirty as in the West: So euphemisms are less necessary. Nevertheless, Japanese high-tech toilets that play music to cover embarrassing noises are popular with women users.

In the nineteenth century it was considered so shocking for a woman to need the toilet when out that little away from home provision was made for women. Women still have approximately half the number of toilet facilities as men, a last vestige of sex discrimination. Standardized toilet manufacturers make little allowance for different user group needs, in terms of ergonomic design. Factory and office workers also suffer from lack of workplace provision, and there is no constitutional right for employees to urinate during company time.

While householders invest in high-quality designer bathrooms, in contrast the poor quality and lack of public toilets has been the cause of great concern to user groups such as the American Restroom Association (ARA). The ARA argues the business case that bathrooms mean business as better public restrooms will result in more tourists, shoppers, and visitors coming to town, staying longer, and spending more.

Public toilets, because they are public, are contested spaces, offering anonymity and seclusion to drug users and deviant groups. News reports of people being born, dying, being raped, trapped, attacked, or arrested in toilets are frequent. They are one of the few places where complete strangers mix and share intimate facilities. They repel those worried about picking up a sexually transmitted disease; women warn their daughters not to sit on the seat for hygienic purposes. They attract men who are cruising (cottaging, or looking for a date): the subject of many sociological and criminological studies. Toilet closure is often seen as the way to reduce crime. But closure greatly inconveniences bona fide users, as evidenced by a new generation of research on the practical needs of women and other social groups that are disenabled by the design of the built environment.

One can judge a nation by its toilets. When visiting a foreign country, the first necessity that people are likely to look for is the toilet, and the image and smell remain with them. The nature of toilet provision is an indicator of whose needs are valued in society and what a society thinks about women, babies, children, workers, and its elderly and disabled citizens.

SEE ALSO Development; Development Economics; Disease; Plumbing; Public Health; Sanitation

BIBLIOGRAPHY

Armstrong, David. 1993. Public Health Spaces and the Fabrication of Identity. Sociology 27 (3): 393410.

Gandy, Matthew. 2004. Water, Modernity and Emancipatory Urbanism. In The Emancipatory City: Paradoxes and Possibilities, ed. L. Lees, 178191. London: Sage.

Greed, Clara. 2003. Inclusive Urban Design: Public Toilets.Oxford: Elsevier.

Kira, Alexander. 1976. The Bathroom. London: Cornell University Press.

Linder, Marc, and Nygaard, Ingrid. 1998. Void Where Prohibited: Rest Breaks and the Right to Urinate on Company Time. Ithaca, NY: Cornell University Press.

Wright, Lawrence. 2000. Clean and Decent: The Fascinating History of the Bathroom and WC. London: Penguin.

Clara H. Greed

Toilets

views updated May 23 2018

Toilets


The origin of the indoor toilet for the disposal of human wastes goes far back in history. Archaeologists found in the palace of King Minos on Crete an indoor latrine that had a wooden seat and may have worked like a modern flush toilet; they also discovered a water-supply system of terra cotta pipes to provide water for the toilet. Between 2500 and 1500 b.c., cities in the Indus Valley also had indoor toilets that were flushed with water. The wastewater was carried to street drains through brick-lined pits. In 1860, Reverend Henry Moule invented the earth closet, a wooden seat over a bucket and a hopper filled with dry earth, charcoal, or ashes. The user of the toilet pulled a handle to release a layer of earth from the hopper over the wastes in the bucket. The container was emptied periodically. During the eighteenth and nineteenth centuries in Europe, human wastes were deposited in pan closets or jerry pots. After use, the pots were emptied or concealed in commodes. The contents of the jerry pots were often collected by nearby farmers who used the wastes as organic fertilizer . However, as cities grew larger, transportation of the wastes to farms became uneconomical, and the wastes were dumped into communal cesspits or into rivers. The flush toilet common in use today was supposedly invented by Thomas Crapper in the nineteenth century; Wallace Rayburn wrote a biography of Crapper, titled Flushed with Pride, in 1969.

The development of the flush toilet was primarily responsible for the development of the modern sanitary system, consisting of a maze of underground pipes, pumps, and centralized treatment systems. Modern sanitary systems are efficient in removing human and other wastes from human dwellings but are costly in terms of capital investment in the infrastructure, operational requirements, and energy requirements. The treated wastewater is usually disposed of in rivers and lakes, sometimes causing adverse impacts upon the receiving waters.

Sanitary systems require an abundant supply of water, and the flush toilet is responsible for the largest use of water in the home. Each flush of a conventional water-carriage toilet uses between 47 gal (1526 L) of water, depending on the model and water supply pressure. The average amount of water used per flush is 4.3 gal (16 L). Since each person flushes the toilet an average of 3.5 times per day, the average daily flow per person is approximately 16 gal (60 L) for a yearly flow of 5,840 gal (22,104 L).

To reduce the volume of water used for flushing, a variety of devices are available for use with a conventional flush toilet. These devices include:

  • Tank insert - a displacement device placed in storage tank of conventional toilets to reduce the volume (but not the height) of stored water.
  • Dual flush toilet - devices used with conventional toilets to enable the user to select from two flush volumes, based on the presence of solid or liquid waste materials.
  • Water-saving toilet - variation of conventional toilet with redesigned flushing rim and priming jet that allows the initiation of the siphon flush in a smaller trapway with less water.
  • Pressurized and compressed air (assisted flush toilet) variation of conventional toilet designed to utilize compressed air to aid in flushing by propelling water into the bowl at increased velocity.
  • Vacuum-assisted flush toilet - variation of conventional toilet in which the fixture is connected to a vacuum system that is used to assist a small amount of water in flushing.

In addition to modifications to conventional flush toilets, non-water carriage toilets are available to reduce the amount of water required. They are also used for disposing of toilet wastes. Types of non-water carriage toilet systems include:

  • Composting toilet - self-contained units that accept toilet wastes and utilize the addition of heat in combination with aerobic biological activity to stabilize human excreta; larger units may accept other organic wastes in addition to toilet wastes and requires periodic disposal of residuals.
  • Incinerating toilet - small self-contained units that utilize a burning assembly or heating element to volatilize the organic components of human waste and evaporate the liquids; requires periodic disposal of residuals.
  • Oil-recycle toilets - self-contained unit that uses a mineral oil to transport human excreta from a toilet fixture to a storage tank; oil is purified and reused for flushing; requires removal and disposal of excreta from storage tank periodically (usually annually).

The wastes from toilets are referred to as "blackwater." If the wastes from toilets are segregated and handled separately using alternative non-water carriage toilets from the wastewaters generated from other fixtures in the home (referred to as "graywater"), significant quantities of pollutants, especially suspended solids, nitrogen , and pathogenic organisms, can be eliminated from the total wastewater flow. Graywater, though it still may contain significant numbers of pathogenic organisms, may be simpler to manage than total residential wastewater due to a reduced flow volume.

See also Municipal solid waste; Sewage treatment

[Judith Sims ]


RESOURCES

PERIODICALS

Love, S. "An Idea in Need of Rethinking: The Flush Toilet." Smithsonian 6 (1975): 6166.

Rodale, R. "Goodbye to the Flush Toilet." Compost Science 12 (1971): 2425.

OTHER

U.S. Environmental Protection Agency. Design Manual: Onsite Wastewater Treatment and Disposal Systems. Cincinnati, OH: Municipal Environmental Research Laboratory, U.S. Environmental Protection Agency, 1980.

toilet

views updated May 21 2018

toi·let / ˈtoilit/ • n. 1. a large bowl for urinating or defecating into, typically plumbed into a sewage system and with a flushing mechanism: Liz heard the toilet flush| fig. my tenure was down the toilet. ∎  a room, building, or cubicle containing one or more of these.2. [in sing.] the process of washing oneself, dressing, and attending to one's appearance: her toilet completed, she finally went back downstairs. ∎  [as adj.] denoting articles used in this process: a bathroom cabinet stocked with toilet articles. ∎  the cleansing of part of a person's body as a medical procedure.• v. (-let·ed, -let·ing) [tr.] [usu. as n.] (toileting) assist or supervise (someone, esp. an infant or invalid) in using a toilet.ORIGIN: mid 16th cent.: from French toilette ‘cloth, wrapper,’ diminutive of toile (see toile). The word originally denoted a cloth used as a wrapper for clothes; then (in the 17th cent.) a cloth cover for a dressing table, the articles used in dressing, and the process of dressing, later also of washing oneself (sense 2). In the 19th cent. the word came to denote a dressing room, and, in the U.S., one with washing facilities; hence, a lavatory (early 20th cent.).

toilet

views updated May 23 2018

toilet †cloth wrapper XVI; cloth cover for a dressing table, furniture of this, the table itself; dressing XVII; (lady's) dress XIX. — F. toilette, dim. of toile cloth, etc.; *prec.. -ET.