Chair

When English-speaking philosophers talk about the material world as opposed to ideas, their phrase is tables and chairs. Poland issued a fan-shaped 10 zloty coin but the oddest coin ever was the 2002 Nauru,Europe-shaped coin. Activities that are likely to be made insignificant or undone by some future event are said to be like rearranging the deckchairs on the Titanic. Coins with guitar shapes were issued in Somalia this year. If you nearly fell off your chair, it was because you were very surprised. Bi-metallic coins are used for comemorative purposes and in the 1990s,France used a tri-metallic coin. A movie or a story is said to keep you on the edge of your chair, if it is suspenseful and engaging. Some coins, called bracteates, are so thin they can only be struck on one side.

They are counter-weighted so as to not slide off the arms under the weight of the remote control. Such a coin is often said to be "weighted.". Remote control bags can be draped over the arm of easy chairs or sofas and used to hold remote controls. Coins are sometimes falsified to make one side weigh more. They come in various shapes, some specifically sized to fit partially under a desk. See also coin flipping. This allows chairs on wheels to roll easily over the carpet and it protects the carpet. A widely publicized example of an asymmetrical coin is the Belgian one euro coin(reference needed).

Chair mats are plastic mats meant to cover carpet. See Bernoulli trial; a fair coin is defined to have the probability of heads (in the parlance of Bernoulli trials, a "success") of exactly 0.5. Car seats sometimes have built-in and adjustable lumbar supports. Coins are popularly used as a sort of two-sided die; in order to choose between two options with a random possibility, one choice will be labeled "heads" and the other "tails," and a coin will be flipped or "tossed" to see whether the heads or tails side comes up on top. Obus Forme is a major brand in this category and helped develop this market niche. Some older such designs remain, such as the 12-sided Australian 50 cent coin. Orthopedic backrests provide support for the back. If a coin had an even number of sides this would not be true.

In cars, they may be used to increase the height of the driver. This is so that the coin has a constant diameter, and therefore will be recognised by machines whichever way it is inserted. Some are decorative. Coins that are not round (British 50 pence for example) usually have an odd number of sides, with the edges rounded off. Chair pads are cushions for chairs. Some coins have coin orientation, where the coin must be flipped vertically to see the other side; other coins, such as British coins, have medallic orientation, where the coin must be flipped horizontally to see the other side. In the second half of 20th century, some people used custom clear plastic covers for expensive sofas and chairs to protect them. The orientation of the obverse with respect to the reverse differs between countries.

Covers for sofas and couches are also available for homes with small children and pets. [1] Another rule is that the side carrying the year of minting is the obverse, although most Canadian coins, and all Japanese coins, are an exception. The chair covers may come with decorative chair ties, a ribbon to be tied as a bow behind the chair. However, the rule is violated in some cases. They are typically rented for formal events such as wedding receptions to increase the attractiveness of the chairs and decor. The back side is called the reverse, or colloquially tails. A chair cover is a temporary fabric cover for a side chair. Traditionally the side of a coin carrying a bust of a monarch or other authority, or a national emblem, is called the obverse, or colloquially heads.

If matched to a glider, the ottoman may be mounted on swing arms so that the ottoman rocks back and forth with the main glider. The monarch would have to periodically recall, paying only bullion value of the silver, and re-mint circulating coins. An ottoman is a short stool to be used as a footrest but can sometimes be used as a stool. This form of debasement in Tudor England led to the formulation of Gresham's Law. In place of a built-in footrest, some chairs come with a matching ottoman. Circulating unmilled British sterling silver coins were known to be shaved to almost half of their minted weight. Canada's Canadian General Standards Board CAN/CGSB 44.15M [6] on "Straight Stacking Chair, Steel"). This is the reason some modern coins have ridges, known as "reeds," on their edges; the presence of reeding shows that the coin's edge has not been shaved.

Governments will often issue standards for purchases by government agencies (e.g. Prior to the use of milled edges, circulating coins suffered from "shaving," a common problem where unscrupulous persons would shave a small amount of precious metal from the edge of a circulating coin. Large institutions that make bulk purchases will reference these standards within their own even more detailed criteria for purchase [5]. The milled, or reeded, edges still found on many coins were originally designed to show that none of the valuable metal had been shaved off the coin. Under these higher loads, the chair may be damaged, but it must not fail catastrophically. Increasingly common are coin counting machines which charge money to consumers for converting their "coins" into "cash". The specification further defines heavier "proof" loads that chairs must withstand. has never revised its coinage system to accommodate this inflation, and as a result, coins in America today are scarcely regarded as "money" in any practical sense.

It specifies things like[4]:. What is unique to the United States, among the developed countries, is that the U.S. The Business and Institutional Furniture Manufacturer's Association (BIFMA) defines BIFMA X5.1 for testing of commercial-grade chairs. The United Kingdom saw similar inflation during the same era. ASTM E1822-02b defines the combustibility of chairs when they are stacked. Virtually every other country debased their coinage too. ASTM F1858-98 specifies lawn chairs. It also should not be inferred that such debasement and inflation were unique to the U.S.

ISO 7174 specifies stability of rocking and tilting chairs. For example, in 1960, the silver in a dime was worth less than four cents. Bean bag chairs are specified by ANSI standard ASTM F1912-98[3]. silver coinage, such coins were actually fiat money, because the value of silver was relatively low. Dental chairs are specified by ISO 6875. It should be remembered, however, that for most of the era of U.S. There are multiple specific standards for different types of chairs. Some consider a classic example of this phenomenon to be the behavior of price levels in the United States since 1964 (the last year circulating United States Coins were minted of 90 percent silver).

ISO 9241-5:1988[2], "Ergonomic requirements for office work with visual display terminals (VDTs) -- Part 5: Workstation layout and postural requirements " is the most common one for modern chair design. Debasement of money almost always leads to price inflation unless price controls are also instituted by the governing authority. Design considerations for chairs have been codified into standards. By replacing some fraction of a coin's precious metal content with a base metal (often copper or nickel), the intrinsic value of each individual coin was reduced (thereby "debasing" their money), allowing the coining authority to produce more coins than would otherwise be possible. Open center seats where a soft material is attached to the tops of chair legs or between stretchers to form the seat. Throughout history, governments have been known to create more coinage than their supply of precious metals would allow. Some systems include: Solid center seats where a solid material forms the chair seat. For example, in 1979 and 1980, a Chinese architectural team excavating the region surrounding the ancient kingdom of Loulan discovered some Mesolithic stone tools and coins (see Loulan: Modern Chinese Expeditions).

Chair seats vary widely in construction and may or may not match construction of the chair's back. The history of coins is a long and interesting one. See also seats in movie theaters, and pictures of benches with and without arm rests. True coins also developed very close to this time frame in both India and China. A loveseat in particular, has no arm rest in between. Under three generations of Lydian kings, the money of Lydia gradually moved from being lumps of electrum (a naturally occurring alloy of silver and gold) to coins of a guaranteed weight and purity, marked with the seal of the King. Arm rests prevent or complicate both desired and undesired proximity. By the above definition, the invention and first known usage of coins comes from the Kingdom of Lydia circa 643-630 B.C.

in public transport and other public places, and to prevent lying on the bench or coach. These criteria are:. The latter may be provided for comfort, but also for privacy e.g. To distinguish between these two types of coins, as well as from other forms of tokens which have been used as money, monetary scholars have defined three criteria that an object must meet to be a "true coin". A couch, bench, or other arrangement of seats next to each other may have arm rest at the sides and/or arm rests in between. This means that the value of the coin is decreed by government fiat rather than agreed by the people, which really makes it less a coin and more a token in the strictest sense. Hence in some chair designs, the armrest is not continuous to the chair back, but is missing in the elbow area. However, in modern times, most coins are made of a base metal and their value comes strictly from their status as fiat money.

Armrests should support the forearm and not the sensitive elbow area. The market exchange value of a coin comes from its historic value, and/or the intrinsic value of the component metal (for example gold coins, silver coins or platinum coins). Armrests further have the function of making entry and exit from the chair easier (but from the side it becomes more difficult). See Coin collecting and Numismatics for more information on the collecting of coins, bank notes, token coins and Exonumia. If so, armrests will support part of the body weight through the arms if the arms are resting on the armrests. . A chair may or may not have armrests. Coins are usually used for lower-valued units, and banknotes are usually used for the higher values; also, in most money systems, the highest value coin is worth less than the lowest-value note.

For adjustable chairs, the aforementioned principles are applied in adjusting the chair to the individual occupant. Along with banknotes, coins make up the cash forms of all modern money systems. In some airplanes and stadiums the seat pitch is so small that there is sometimes there is no leg room for the average person. A coin is usually a piece of hard material, generally metal and usually in the shape of a disc, which is issued by a government to be used as a form of money. "Seat pitch" is the distance between rows of seats. It must be marked to identify the authority that guarantees the content. The buttock-knee length is used to determine "leg room" between rows of chairs. It must be of a standardized weight and purity.

Elbow rest height is used to determine the height of the armrests. It must be made of a valuable material, and trade for close to the market value of that material. Hip breadth is used for chair width and armrest width. Additional anthropometric measurements may be relevant to designing a chair. Mass produced chairs are typically 38-43 cm deep.

This anthropometric measurement is used to determine the seat depth. For someone seated, the buttock popliteal length is the horizontal distance from the back most part of the buttocks to the back of the lower leg. Mass produced chairs are typically 17 inches high. The popliteal height, after adjusting for heels, clothing and other issues is used to determine the height of the chair seat.

(The term "sitting height" is reserved for the height to the top of the head when seated.) For American men, the median popliteal height is 16.3 inches and for American women it is 15.0 inches[1]. It is sometimes called the "stool height". For someone seated, the popliteal height is the distance from the underside of the foot to the underside of the thigh at the knees. The two most relevant anthropometric measurement for chair design is the popliteal height and buttock popliteal length.

Anthropometric statistics may be gathered for mass produced chairs. Individuals may be measured for a custom chair. Actual chair dimensions are determined by measurements of the human body or anthropometric measurements. By matching the shape of the occupant's buttocks, weight is distributed and pressure at any given point is reduced.

A contoured seat pan attempts to distribute weight without padding. Where padding is not desirable, contouring may be used instead. For example, in hot climates, padding with fabric or plastic covers is often uncomfortable against the skin. There may be cases where padding is not desirable.

Chairs that have padding that is the same density front and back will feel soft in the back area and hard to the underside of the knees. Since most of the body weight is supported in the back of the seat, padding there should be firmer than the front of the seat which only has the weight of the legs to support. In lieu of padding, flexible materials, such as wicker, may be used instead with similar effects of distributing the weight. Spreading the area reduces the pressure at any given point.

The same body weight over a smaller area means greater pressure on that area. A hard wood chair feels hard because the contact point between the occupant and the chair is small. However, padding does distribute the weight by increasing the area of contact between the chair and the body. Padding will not shift the weight to different parts of the body (unless the chair is so soft that the shape is altered).

Padding can be on the seat of the chair only, on the seat and back, or also on any arm rests and/or foot rest the chair may have. Many chairs are padded or have cushions. A sit-stand chair distributes most of the weight of the occupant to the feet. A kneeling chair adds an additional body part, the knees, to support the weight of the body.

A stool or other simple chair may have a simple straight or curved bar near the bottom for the sitter to place his/her feet on. Some chairs have foot rests. Reclining chairs typically have at least shoulder height backrests to shift weight to the shoulders instead of just the lower back. Headrests support the head as well and are important in vehicles for preventing "whiplash" neck injuries in rear-end collisions where the head is jerked back suddenly.

Shoulder height backrests support the entire back and shoulders. In general, backrests come in three heights: Lower back backrests support only the lumbar region. The back of the chair will support some of the weight of the occupant, reducing the weight on other parts of the body. However, reclining may not be suitable for chairs intended for work or eating at table.

In general, if the occupant is suppose to sit for a long time, weight needs to be taken off the seat area and thus "easy" chairs intended for long periods of sitting are generally at least slightly reclined. This may be more comfortable for some in reducing weight on the seat area, but may be problematic for others who have bad backs. A reclining seat and back will shift weight to the occupant's back. A lower seat may shift too much weight to the "seat bones" ("ischial tuberosities").

It may also result in no weight on the feet which means more weight elsewhere. A seat that is higher results in dangling feet and increased pressure on the underside of the knees ("popliteal fold"). Ergonomic designs distributes the weight of the occupant to various parts of the body. Easy chairs for watching television or movies are somewhere in between depending on the height of the screen.

Dental chairs are necessarily reclined. "Task chairs", or any chair intended for people to work at a desk or table, including dining chairs, can only recline very slightly; otherwise the occupant is too far away from the desk or table. Intended usage determines the desired seating position. Chair design considers intended usage, ergonomics (how comfortable it is for the occupant), as well as non-ergonomic functional requirements such as size, stackability, foldability, weight, durability, stain resistance and artistic design.

. See history of the chair for an extended look at chairs from antiquity to the modern day. Headrests for seats in vehicles are important for preventing whiplash injuries to the neck when the vehicle is involved in a rear-end collision. There may be separate headrests.

The back may extend above the height of the head. Likewise, the back and sometimes the seat are made of porous materials or have holes drilled in them for decoration and ventilation. The back often does not extend all the way to the seat to allow for ventilation. Chairs as furniture are typically not attached to the floor and so can be moved.

A chair mounted in a vehicle or in a theatre is simply called a seat. A separate footrest for a chair is known as an ottoman, hassock or poof. A chair for more than one person is a couch, sofa, settee, loveseat (two-seater without arm rest in between) or bench. Without back and arm rests it is called a stool.

Chairs also often have legs to support the seat raised above the floor. A chair is a piece of furniture for sitting, consisting of a seat, a back, and sometimes arm rests, commonly for use by one person. seat cycle strength of 100,000 repetitions of 125 pounds (57 kg) dropped from 2 inches (50 mm) above the seat. seat strength of 225 pounds (102 kg) dropped from six inches (150 mm) above the seat.

leg strength of 75 pounds (34 kg) applied one inch (25 mm) from the bottom of the leg. chair stability if weight is transferred completely to the front or back legs. chair backstrength of 150 pounds (68 kg). Metal, Metal mesh or wire woven to form seat.

Splint, ash, oak or hickory strips are woven. Caning, woven from rush, reed, rawhide, heavy paper, strong grasses, cattails to form the seat, often in elaborate patterns. Tape, wide fabric tape woven into seat, seen in lawn chairs and some old chairs. Fabric, simple covering without support.

Leather, may be tooled with a design. Wicker, woven to provide a surface with give to it. Stone, often marble. Molded plastic.

Metal seats of solid or open design. Stuffed fabric, similar to padded leather. Padded leather, generally a flat wood base covered in padding and contained in soft leather. Wood slats, often seen on outdoor chairs.

Solid wood, may or may not be shaped to human contours.