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For the race in The Hitchhiker's Guide to the Galaxy, see Mattresses.
A mattress is a mat or pad, usually placed on top of a bed, upon which to sleep or lie. The word mattress is derived from Arabic words meaning "to throw" and "place where something is thrown" or "mat, cushion." During the Crusades, Europeans adopted the Arabic method of sleeping on cushions thrown on the floor, and the word materas eventually descended into Middle English through the Romance languages.1 Though a mattress may be placed directly on the floor, it is usually placed on top of a platform (such as a platform bed or a metal box spring or a slatted foundation) to be further from the ground. Historically, mattresses have been filled with a variety of natural materials, including straw and feathers. Modern mattresses usually contain either an inner spring core or materials such as latex, viscoelastic, or other polyurethane-type foams. Mattresses may also be filled with air or water, or a variety of natural fibres, such as in futons.
History
Photo on a 1940 USDA circular promoting home production of cotton mattresses
Mattress dimensionsMost mattresses have a thickness from six to eighteen inches (15 to 46 cm).
Components of an innerspring mattress
A common innerspring mattress consists of three components: the spring core, the foundation, and the upholstery layers. Spring mattress coreThe core of the mattress supports the sleeper’s body. Modern spring mattress cores, often called "innersprings," are made up of steel coil springs, or "coils." The gauge of the coils is another factor which determines firmness and support. Coils are measured in quarter increments. The lower the number, the thicker the spring. In general, higher-quality mattress coils have a 14-gauge (1.63 mm) diameter. Coils of 14 to 15.5-gauge (1.63 to 1.37 mm) give more easily under pressure, while a 12.5-gauge (1.94 mm) coil, the thickest typically available, feels quite firm. Connections between the coils help the mattress retain its shape. Most coils are connected by interconnecting wires; pocketed coils are not connected, but the pockets preserve the mattress shape. There are four different types of mattress coils:
Air mattressesAir mattresses use one or more air chambers instead of springs to provide support. Quality and price can range from inexpensive ones used occasionally for camping, all the way up to high-end luxury beds. Air mattresses designed for typical bedroom use cost about the same as inner-spring mattresses with comparable features. Several companies currently produce adjustable firmness air mattresses. In 1981, Comfortaire began manufacturing and marketing air mattresses that looked conventional but allowed users to adjust the firmness. Select Comfort patented a variant and began marketing them in 1987. Adjustable air mattresses come in a variety of models from basic, no-frills ones that measure about 7" in height, to high-profile, 15" tall hybrids that contain several types of foam, pillow tops, and digital pumps with memory, for individual pressure settings. Air bladder construction varies from a simple polyethylene bag to internally baffled, multiple chambers of latex (vulcanized rubber) with bonded cotton exteriors. Mattresses have a layer of foam above the air chambers for added cushioning. The air chambers, top and sidewall foam all sit inside a removable two piece cover that looks like the outside of a standard innerspring mattress. These high-end luxury Air Beds are also known as soft sided Air Beds. Medical versions of these adjustable firmness mattresses have even greater control mechanisms which include features like frequently changing pressure to prevent bed sores. Foam mattressesFoam mattresses use shape-conforming latex or viscoelastic memory foam rather than springs to provide support. Mattresses manufactured using memory foam or latex are generally hypoallergenic.citation needed Since foam varies in quality, prices can vary widely. Most mattress manufacturers offer a line of memory foam mattresses. FoundationThere are three main types of foundations.
Upholstery layersUpholstery layers cover the mattress and provide cushioning and comfort. Some manufacturers call the mattress core the "support layer" and the upholstery layer the "comfort layer." The upholstery layer consists of three parts: the insulator, the middle upholstery, and the quilt. The insulator separates the mattress core from the middle upholstery. It is usually made of fiber or mesh and is intended to keep the middle upholstery in place. The middle upholstery comprises all the material between the insulator and the quilt. It is usually made from materials which are intended to provide comfort to the sleeper, including regular foam, viscoelastic foam, felt, polyester fibers, cotton fibers, convoluted (“egg-crate”) foam, and non-woven fiber pads. The quilt is the top layer of the mattress. Made of light foam or fibers stitched to the underside of the ticking, it provides a soft surface texture to the mattress and can be found in varying degrees of firmness. The protective fabric cover which encases the mattress is called ticking. It is usually made to match the foundation and comes in a wide variety of colors and styles. Most ticking is made of synthetic fibers like polyester, or acrylic; or of natural materials such as latex, cotton, silk, and wool. QualityMany parameters determine mattress quality. Laboratory test methods have been established for some of these parameters, such as pressure distribution, skin microclimate, hygiene, edge support, and long-term stability. Many of these have been developed by Dr. Duncan Bain, working on behalf of the UK's Medicines and Healthcare products Regulatory Agency.4 Other parameters, such as firmness, are more specific to the sleeper. In general, firm mattresses are recommended for stomach and some back sleepers, soft mattresses are recommended for side sleepers, and medium mattresses are recommended for the majority of back sleepers.citation needed Some brands offer mattresses with one softer side and one firmer side, or with adjustable firmness levels, to accommodate sleepers who share a bed. Mattresses in hospitals"Not all the anti-decubitus mattresses really succeed in reducing the interface pressure. The foam and gel mattresses have no or limited pressure reducing qualities. The polyether mattress and especially the polyurethane slow foam mattress reduce pressure best and are preferable in the prevention of pressure ulcers on an operating table. None of the mattresses tested reduced the pressure sufficiently in lateral position."[1] Maintenance and careA quality innerspring mattress should last between 10 and 15 years before it needs to be replaced. Memory foam and latex models should last between 15 and 20 years depending on the manufacturer and the quality of the bedding. This is an approximation, as many factors affect the lifespan of a mattress. Mattresses should be placed atop a firm base to prevent sagging. Mattresses should be rotated approximately once every three months to ensure even wear; in addition, two sided mattresses should be turned over (flipped) twice per year. Folding and bending of the mattress should be avoided if possible, as should heavy wear in one spot and excessive weight on the handles. Mattresses should not be soaked, lest mildew develop inside the upholstery; instead, they can be cleaned with a vacuum or with mild surface cleanser and a slightly damp cloth. Mattress Protectors help prevent stains and soiling of the ticking. Once a mattress no longer feels supportive and instead seems to contribute to body pain or stiffness, it should be replaced. Some symptoms of a broken or worn out mattress include springs which can be felt poking through the upholstery layer, visible permanent sagging or deformity, lumpiness, and excessive squeaking. See also
Notes
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