Imperial unit
Encyclopedia
Weights and Measures Act
A Weights and Measures Act is an Act of Parliament determining trade law where the weight or size of the goods being traded are important. For example, if a bottle of milk is for sale and has a label saying it contains one pint, then the law states that it must contain that amount.-United...
of 1824, which was later refined (until 1959) and reduced. The system came into official use across the British Empire
British Empire
The British Empire comprised the dominions, colonies, protectorates, mandates and other territories ruled or administered by the United Kingdom. It originated with the overseas colonies and trading posts established by England in the late 16th and early 17th centuries. At its height, it was the...
. By the late 20th century, most nations of the former empire had officially adopted
Metrication
Metrication refers to the introduction and use of the SI metric system, the international standard for physical measurements. This has involved a long process of independent and systematic conversions of countries from various local systems of weights and measures. Metrication began in France in...
the metric system
Metric system
The metric system is an international decimalised system of measurement. France was first to adopt a metric system, in 1799, and a metric system is now the official system of measurement, used in almost every country in the world...
as their main system of measurement, although as of 2011 the UK had only partially adopted it.
Length
Since 1959, the US and the British yard have been defined identically to be 0.9144 metres, to match the international yard. Metric equivalents in this article usually assume this latest official definition. Before this date, the most precise measurement of the Imperial Standard Yard was metres.| Unit | Relative to previous | Feet | Millimetres | Metre Metre The metre , symbol m, is the base unit of length in the International System of Units . Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole , its definition has been periodically refined to reflect growing knowledge of metrology... s |
Notes |
|---|---|---|---|---|---|
| thou Thou (unit of length) A thou also known as a mil or point, is the verbalized abbreviation for "thousandth of an inch." It is a unit of length equal to 0.001 inch.... (th) |
0.0254 | 0.000 025 4 | 25.4 μm | ||
| inch Inch An inch is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in a foot... (in) |
1000 thou | 25.4 | 0.025 4 | ||
| foot (ft) | 12 inches | 1 | 304.8 | 0.3048 | |
| yard Yard A yard is a unit of length in several different systems including English units, Imperial units and United States customary units. It is equal to 3 feet or 36 inches... (yd) |
3 feet | 3 | 914.4 | 0.9144 | Defined as exactly 0.9144 metres since 1959 |
| chain (ch) | 22 yards | 66 | 20116.8 | 20.1168 | |
| furlong Furlong A furlong is a measure of distance in imperial units and U.S. customary units equal to one-eighth of a mile, equivalent to 220 yards, 660 feet, 40 rods, or 10 chains. The exact value of the furlong varies slightly among English-speaking countries.... (fur) |
10 chains | 660 | 201.168 | ||
| mile Mile A mile is a unit of length, most commonly 5,280 feet . The mile of 5,280 feet is sometimes called the statute mile or land mile to distinguish it from the nautical mile... (mi) |
8 furlongs | 5,280 | 1,609.344 | ||
| league League (unit) A league is a unit of length . It was long common in Europe and Latin America, but it is no longer an official unit in any nation. The league originally referred to the distance a person or a horse could walk in an hour... (lea) |
3 miles | 15,840 | 4,828.032 | No longer an official unit in any nation. | |
| Maritime units | |||||
| fathom Fathom A fathom is a unit of length in the imperial and the U.S. customary systems, used especially for measuring the depth of water.There are 2 yards in an imperial or U.S. fathom... (ftm) |
~2 yards | 6.08 or 6 | 1,853.184 | The British Admiralty Admiralty The Admiralty was formerly the authority in the Kingdom of England, and later in the United Kingdom, responsible for the command of the Royal Navy... in practice used a fathom as 6 feet. This was despite its being of a nautical mile (i.e. 6.08 feet) until the adoption of the international nautical mile. The commonly accepted definition of a fathom was always 6 feet. The conflict was inconsequential as Admiralty nautical charts designated depths shallower than 5 fathoms in feet on older imperial charts. Today all charts worldwide are metric, except for USA Hydrographic Office charts, which use feet for all depth ranges. |
|
| cable Cable length A cable length or cable's length is a nautical unit of measure equal to one tenth of a nautical mile or 100 fathoms, or sometimes 120 fathoms. The unit is named after the length of a ship's anchor cable in the age of sail... |
100 fathoms | 608 | 185.3184 | One tenth of a nautical mile. When in use it was approximated colloquially as 100 fathoms. | |
| nautical mile Nautical mile The nautical mile is a unit of length that is about one minute of arc of latitude along any meridian, but is approximately one minute of arc of longitude only at the equator... |
10 cables | 6,080 | 1,853.184 | Used to measure distances at sea. Until the adoption of the international definition of 1852 metres in 1970, the British nautical (Admiralty) mile was defined as 6,080 feet. It was not readily expressible in terms of any of the intermediate units, because it was derived from the circumference of the Earth (like the original metre). | |
| Gunter's survey units (17th century onwards) | |||||
| link | 7.92 inches | 201.168 | of a chain | ||
| rod Rod (unit) The rod is a unit of length equal to 5.5 yards, 5.0292 metres, 16.5 feet, or of a statute mile. A rod is the same length as a perch or a pole. In old English, the term lug is also used.-History:... |
25 links | 5,029.2 | 5.0292 | The rod is also called pole or perch. | |
| chain Chain (unit) A chain is a unit of length; it measures 66 feet or 22 yards or 100 links . There are 10 chains in a furlong, and 80 chains in one statute mile. An acre is the area of 10 square chains... |
4 rods | 66 | 20.1168 | of a furlong | |
Area
| Unit | Relation to units of length | Square feet | Square rods | Square miles | Square metres | Hectare Hectare The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2... s |
Notes |
|---|---|---|---|---|---|---|---|
| perch | 1 rod × 1 rod | 272.25 | 1 | Although the proper term is square rod, for centuries this unit has been called a pole or perch or, more properly square pole or square perch. | |||
| rood | 1 furlong × 1 rod | 10,890 | 40 | 0.1012 | The rood is also called a rod. It is 1,210 square yards. | ||
| acre Acre The acre is a unit of area in a number of different systems, including the imperial and U.S. customary systems. The most commonly used acres today are the international acre and, in the United States, the survey acre. The most common use of the acre is to measure tracts of land.The acre is related... |
43,560 | 160 | 0.4047 | One acre is 4,840 square yards | |||
| Note: All equivalences are exact except the hectares, which are accurate to four significant figures. | |||||||
Volume
In 1824, the United Kingdom adopted a close approximation to the ale gallon known as the imperial gallon. The imperial gallon was based on the volume of 10 lbPound (mass)
The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...
of distilled water weighed in air with brass weights with the barometer standing at 30 in Hg
Inch of mercury
Inches of mercury, ' is a unit of measurement for pressure. It is still widely used for barometric pressure in weather reports, refrigeration and aviation in the United States, but is seldom used elsewhere....
at a temperature of 62 °F
Fahrenheit
Fahrenheit is the temperature scale proposed in 1724 by, and named after, the German physicist Daniel Gabriel Fahrenheit . Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to be 212 degrees...
. In 1963 this definition was refined as the space occupied by 10 lb of distilled water of density g
Gram
The gram is a metric system unit of mass....
/mL weighed in air of density against weights of density 8.136 g/mL. This works out to , or . The Weights and Measures Act of 1985 switched to a gallon of exactly (approximately ).
| Unit | Imperial ounce | Imperial pint | Millilitres | Cubic inches | US ounces | US pints |
|---|---|---|---|---|---|---|
| fluid ounce Fluid ounce A fluid ounce is a unit of volume equal to about 28.4 mL in the imperial system or about 29.6 mL in the US system. The fluid ounce is distinct from the ounce, which measures mass... (fl oz) |
1 | 28.4130625 | ||||
| gill (gi) | 5 | 142.0653125 | ||||
| pint Pint The pint is a unit of volume or capacity that was once used across much of Europe with values varying from state to state from less than half a litre to over one litre. Within continental Europe, the pint was replaced with the metric system during the nineteenth century... (pt) |
20 | 1 | 568.26125 | |||
| quart Quart The quart is a unit of volume equal to a quarter of a gallon, two pints, or four cups. Since gallons of various sizes have historically been in use, quarts of various sizes have also existed; see gallon for further discussion. Three of these kinds of quarts remain in current use, all approximately... (qt) |
40 | 2 | 1136.5225 | |||
| gallon Gallon The gallon is a measure of volume. Historically it has had many different definitions, but there are three definitions in current use: the imperial gallon which is used in the United Kingdom and semi-officially within Canada, the United States liquid gallon and the lesser used United States dry... (gal) |
160 | 8 | 4546.09 | |||
| Note: The millilitre equivalences are exact whereas the conversions to cubic-inch and US measures are correct to five significant figures. | ||||||
British apothecaries' volume measures
These measurements were in use from 1824, when the new imperial gallon was defined, but fell out of use long before they were officially abolished in 1971.| Unit | Previous Unit | Metric Value |
|---|---|---|
| minim Minim (unit) The minim is a unit of volume in both the imperial and US customary systems of measurement. Specifically it is of a fluidram or of a fluid ounce.... |
... | 59.1938802 µl |
| fluid scruple | 20 minims | 1.1838776 ml |
| fluid drachm Dram (unit) The dram was historically both a coin and a weight. Currently it is both a small mass in the Apothecaries' system of weights and a small unit of volume... |
3 fluid scruples | 3.5516328 ml |
| fluid ounce | 8 fluid drachms | 28.4130625 ml |
| pint | 20 fluid ounces | 568.26125 ml |
| gallon | 8 pints | 4.54609 l |
Mass
In the 19th and 20th centuries the UK used three different systems for mass and weight:- troy weightTroy weightTroy weight is a system of units of mass customarily used for precious metals, gemstones, and black powder.There are 12 troy ounces per troy pound, rather than the 16 ounces per pound found in the more common avoirdupois system. The troy ounce is 480 grains, compared with the avoirdupois ounce,...
, used for precious metals; - avoirdupoisAvoirdupoisThe avoirdupois system is a system of weights based on a pound of 16 ounces. It is the everyday system of weight used in the United States and is still widely used to varying degrees by many people in Canada, the United Kingdom, and some other former British colonies despite the official adoption...
weight, used for most other purposes; and - apothecaries' weight, now virtually unused since the metric system is used for all scientific purposes.
The troy pound was made the primary unit of mass by the 1824 Act; however, its use was abolished in the UK on 6 January 1879, making the Avoirdupois pound the primary unit of mass with only the troy ounce and its decimal
Decimal
The decimal numeral system has ten as its base. It is the numerical base most widely used by modern civilizations....
subdivisions retained. In all the systems, the fundamental unit is the pound
Pound (mass)
The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...
, and all other units are defined as fractions or multiples of it.
| Unit | Pounds | grams | kilogram Kilogram The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water... s |
Notes |
|---|---|---|---|---|
| grain (gr) | Exactly milligrams. | |||
| drachm Dram (unit) The dram was historically both a coin and a weight. Currently it is both a small mass in the Apothecaries' system of weights and a small unit of volume... (drc) |
1.7718451953125 | |||
| ounce Ounce The ounce is a unit of mass with several definitions, the most commonly used of which are equal to approximately 28 grams. The ounce is used in a number of different systems, including various systems of mass that form part of the imperial and United States customary systems... (oz) |
||||
| pound Pound (mass) The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement... (lb) |
1 | Exactly grams by definition. | ||
| stone (st) | 14 | A person's weight is often quoted in stone and pounds in English-speaking countries using the avoirdupois system, with the exception of the United States and Canada, where it is usually quoted in pounds. | ||
| quarter (qtr) | 28 | One quarter is equal to two stone or a quarter of a hundredweight. The term quarter was also commonly used to refer to a quarter of a pound in a retail context. | ||
| hundredweight Hundredweight The hundredweight or centum weight is a unit of mass defined in terms of the pound . The definition used in Britain differs from that used in North America. The two are distinguished by the terms long hundredweight and short hundredweight:* The long hundredweight is defined as 112 lb, which... (cwt) |
112 | One imperial hundredweight is equal to eight stone. This is the long hundredweight as opposed to the short hundredweight of 100 pounds as used in the United States. | ||
| ton Long ton Long ton is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. It has been mostly replaced by the tonne, and in the United States by the short ton... (t) |
2240 | As with the US system twenty hundredweights equal a ton. However, since the imperial hundredweight is 12% greater than the US equivalent, the imperial ton (or long ton) is 2,240 pounds, which is very close to a tonne Tonne The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI... , compared to the short ton of 2000 pounds (907.185 kg). |
Relation to other systems
The imperial system is one of many systems of English or foot-pound-second units, so named because of the base units of length, mass and time. Although most of the units are defined in more than one system, some subsidiary units were used to a much greater extent, or for different purposes, in one area rather than the other. The distinctions between these systems are often not drawn precisely.One such distinction is that between these systems and older British/English units/systems or newer additions. The term imperial should not be applied to English units that were outlawed in the Weights and Measures Act 1824 or earlier, or which had fallen out of use by that time, nor to post-imperial inventions such as the slug or poundal
Poundal
The poundal is a unit of force that is part of the foot-pound-second system of units, in Imperial units introduced in 1877, and is from the specialized subsystem of English Absolut ....
.
United States customary units
The US customary systemUnited States customary units
United States customary units are a system of measurements commonly used in the United States. Many U.S. units are virtually identical to their imperial counterparts, but the U.S. customary system developed from English units used in the British Empire before the system of imperial units was...
is historically derived from the English units which were in use at the time of settlement. Because the United States was already independent at the time, these units were unaffected by the introduction of the imperial system. Units of length and area are mostly shared between the imperial and US systems, albeit being partially and temporarily defined differently. Capacity measures differ the most due to the introduction of the imperial gallon
Gallon
The gallon is a measure of volume. Historically it has had many different definitions, but there are three definitions in current use: the imperial gallon which is used in the United Kingdom and semi-officially within Canada, the United States liquid gallon and the lesser used United States dry...
and the unification of wet and dry measures. The avoirdupois
Avoirdupois
The avoirdupois system is a system of weights based on a pound of 16 ounces. It is the everyday system of weight used in the United States and is still widely used to varying degrees by many people in Canada, the United Kingdom, and some other former British colonies despite the official adoption...
system applies only to weights; it has a long designation and a short designation for the hundredweight and ton.
Current use of imperial units
United Kingdom
British law now defines each imperial unit in terms of the metric equivalent. The metric system is in official use within the United Kingdom for some applications; however, use of Imperial unit is widespread in many cases.The Units of Measurement Regulations 1995 require that all measuring devices used in trade or retail be capable of measuring and displaying metric quantities. This has now been proven in court against the so-called "Metric Martyrs
Metric Martyrs
The Metric Martyrs are a British advocacy group based in the United Kingdom who campaign for the freedom to choose what units of measurement are presented. The group states that it believes that vendors should have the freedom to mark their goods with any units they choose. This can be solely...
", a small group of market traders who insisted on trading in imperial units only. Contrary to the impression given by some press reports, these regulations do not currently place any obstacle in the way of using imperial units alongside metric units. Almost all traders in the UK will accept requests from customers specified in imperial units, and scales which display in both unit systems are commonplace in the retail trade. Metric price signs may be accompanied by imperial price signs (known as supplementary indicators) provided that the imperial signs are no larger and no more prominent than the official metric ones. The EU units of measurement directive (directive 80/181/EEC) had previously permitted the use of supplementary indicators (imperial measurements) until 31 December 2009, but a revision of the directive published on 11 March 2009 permitted their use indefinitely.
The United Kingdom completed its legal partial transition to the metric system (sometimes referred to as "SI" from the French Système International d'Unités) in 1995, with many imperial units still legally mandated for some application; draught beer must be sold in pints, road-sign distances must be in yards and miles, length and width (but not weight) restrictions must be in feet and inches on road signs (although an equivalent in metres may be shown as well), and road speed limits must be in miles per hour
Miles per hour
Miles per hour is an imperial unit of speed expressing the number of statute miles covered in one hour. It is currently the standard unit used for speed limits, and to express speeds generally, on roads in the United Kingdom and the United States. It is also often used to express the speed of...
, therefore instruments in vehicles sold in the UK must be capable of displaying miles per hour. Foreign vehicles, such as all post-2005 Irish vehicles, may legally have instruments displayed only in kilometres per hour. Even though the troy pound
Troy weight
Troy weight is a system of units of mass customarily used for precious metals, gemstones, and black powder.There are 12 troy ounces per troy pound, rather than the 16 ounces per pound found in the more common avoirdupois system. The troy ounce is 480 grains, compared with the avoirdupois ounce,...
was outlawed in the UK in the Weights and Measures Act of 1878, the troy ounce still may be used for the weight of precious stones and metals. The railways are also a big user of imperial units, with distances officially measured in miles and yards or miles and chains, and also feet and inches, and speeds are in miles per hour, although many modern metro and tram systems are entirely metric, and London Underground
London Underground
The London Underground is a rapid transit system serving a large part of Greater London and some parts of Buckinghamshire, Hertfordshire and Essex in England...
uses both metric (for distances) and imperial (for speeds). Metric is also used for the Channel Tunnel
Channel Tunnel
The Channel Tunnel is a undersea rail tunnel linking Folkestone, Kent in the United Kingdom with Coquelles, Pas-de-Calais near Calais in northern France beneath the English Channel at the Strait of Dover. At its lowest point, it is deep...
and on High Speed 1. Adjacent to Ashford International railway station
Ashford International railway station
Ashford International railway station serves Ashford in Kent, England. Services are provided by Southeastern, Southern and Eurostar.International services use platforms 3 & 4, whilst domestic trains use the original platforms 1 & 2, and a new island built when the Channel Tunnel opened...
and Dollands Moor Freight Yard
Dollands Moor Freight Yard
Dollands Moor Freight Yard is a railway freight yard near Folkestone in Kent, and was purposely built in 1988 for the Channel Tunnel. It is to the west of the Eurotunnel Folkestone Terminal, and just to the south of the M20 Motorway.- External links :*...
, railway speeds are given in both metric and imperial units.
The use of SI units is required by law for the retail sale of some foods and other commodities, whilst imperial units are required for others. Many British people still use imperial units in everyday life for distance (yards, feet and inches), weight (especially stones and pounds) and volume (gallons & pints). Milk is available in both litre and pint based containers. Most people still measure their weight in stone and pounds, and height in feet and inches (but these must be converted to metric if recorded officially, for example in medical records). Petrol is often quoted as being so much per gallon, despite having been sold exclusively in litres for two decades. Likewise, fuel consumption for cars is still almost always in miles per gallon, though official figures always include litres per 100 km equivalents. Fahrenheit equivalents are occasionally given after Celsius in weather forecasts, though this is becoming rare. Threads on non-metric nuts and bolts etc., are sometimes referred to as Imperial, especially in the UK.
Areas of land associated with farming or forestry are bought and sold measured in acres, but for official government areas the unit is always hectares.
Canada
In 1973 the metric system and SI units were introduced in Canada to replace the imperial system. Within the government, efforts to implement the metric system were extensive; almost any agency, institution, or function provided by the government uses SI units exclusively. Imperial units were eliminated from all road signs, although both systems of measurement will still be found on privately owned signs, such as the height warnings at the entrance of a multi-storey parking facilityMulti-storey car park
A multi-storey car-park is a building designed specifically to be for car parking and where there are a number of floors or levels on which parking takes place...
. In the 1980s, momentum to fully convert to the metric system stalled when the government of Brian Mulroney
Brian Mulroney
Martin Brian Mulroney, was the 18th Prime Minister of Canada from September 17, 1984, to June 25, 1993 and was leader of the Progressive Conservative Party of Canada from 1983 to 1993. His tenure as Prime Minister was marked by the introduction of major economic reforms, such as the Canada-U.S...
was elected. There was heavy opposition to metrication and as a compromise the government maintains legal definitions for and allows use of imperial units as long as metric units are shown as well. The law requires that measured products (such as fuel and meat) be priced in metric units, although an imperial price can be shown if a metric price is present. However, there tends to be leniency in regards to fruits and vegetables being priced in imperial units only. However unlike in the rest of Canada, metrication in the Francophone
Francophone
The adjective francophone means French-speaking, typically as primary language, whether referring to individuals, groups, or places. Often, the word is used as a noun to describe a natively French-speaking person....
province of Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
has been more implemented and metric measures are more consistently used in Quebec than elsewhere in Canada both officially and among the population.
Environment Canada
Environment Canada
Environment Canada , legally incorporated as the Department of the Environment under the Department of the Environment Act Environment Canada (EC) (French: Environnement Canada), legally incorporated as the Department of the Environment under the Department of the Environment Act Environment...
still offers an imperial unit option beside metric units, even though weather is typically measured and reported in metric units in the Canadian media. However, some radio stations near the United States border (such as CIMX and CIDR
CIDR-FM
CIDR-FM is the callsign for a radio station, broadcasting at 93.9 FM in Windsor, Ontario. The station broadcasts a adult album alternative format using the brand name 93-9 The River. It is owned and operated by Bell Media. It is one of the few commercial adult album alternative stations in Canada...
) primarily use imperial units to report the weather. Railways in Canada also continue to use Imperial units.
Imperial units are still used in ordinary conversation. Many Canadians use Imperial units to describe their weight and height; newborns are measured in SI at hospitals, but the birth weight and length is usually announced to family and friends in imperial units. Drivers' licences use SI units. In livestock auction markets, cattle are sold in dollars per hundredweight
Hundredweight
The hundredweight or centum weight is a unit of mass defined in terms of the pound . The definition used in Britain differs from that used in North America. The two are distinguished by the terms long hundredweight and short hundredweight:* The long hundredweight is defined as 112 lb, which...
(short), whereas hogs are sold in dollars per hundred kilograms. Imperial units still dominate in recipes, construction, house renovation and gardening. Land is now surveyed and registered in metric units, although initial surveys used imperial units. For example, partitioning of farm land on the prairies in the late 19th and early 20th centuries was done in imperial units; this accounts for imperial units of distance and area retaining wide use in the Prairie Provinces. The size of most apartments, condominiums and houses continues to be described in square feet rather than square metres, and carpet or flooring tile is purchased by the square foot. Motor-vehicle fuel consumption is reported in both litres per 100 km and statute miles per imperial gallon, leading to the erroneous impression that Canadian vehicles are 20% more fuel-efficient than their apparently identical American counterparts for which fuel economy is reported in statute miles per US gallon (Neither country specifies which gallon is used). Canadian railways maintain exclusive use of imperial measurements to describe train length (feet), train height (feet), capacity (tons), speed (mph), and trackage (miles).
Imperial units also retain common use in firearms and ammunition. Imperial measures are still used in the description of cartridge types, even when the cartridge is of relatively recent invention (e.g., 0.204 Ruger
Sturm, Ruger
Sturm, Ruger & Company, Incorporated is a Southport, Connecticut-based firearm manufacturing company, better known by the shortened name Ruger. Sturm, Ruger produces bolt-action, semi-automatic, full-automatic, and single-shot rifles, shotguns, semi-automatic pistols, and single- and double-action...
, 0.17 HMR, where the calibre is expressed in decimal fractions of an inch). However, ammunition which is classified in metric already is still kept metric (e.g., 9 mm). In the manufacture of ammunition, bullet and powder weights are expressed in terms of grains
Grain (measure)
A grain is a unit of measurement of mass that is nominally based upon the mass of a single seed of a cereal. From the Bronze Age into the Renaissance the average masses of wheat and barley grains were part of the legal definition of units of mass. However, there is no evidence of any country ever...
for both metric and imperial cartridges.
As in most of the western world
Western world
The Western world, also known as the West and the Occident , is a term referring to the countries of Western Europe , the countries of the Americas, as well all countries of Northern and Central Europe, Australia and New Zealand...
, air navigation is based on nautical units, e.g., the nautical mile
Nautical mile
The nautical mile is a unit of length that is about one minute of arc of latitude along any meridian, but is approximately one minute of arc of longitude only at the equator...
, which is neither imperial nor metric.
Australia
In Australia, imperial measurements are still encountered peripherally in either spoken or written form.Rural land areas are sometimes given in acres. Australian beer glass sizes are based on older imperial sizes but rounded to the nearest 5 ml, while some surf reports are given in feet.
Republic of Ireland
The Republic of Ireland has officially changed over to the metric system since entering the European UnionEuropean Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
, with distances on new road signs being metric since 1977 and speed limits being metric since 2005. The imperial system remains in limited use - for sales of beer in pubs (traditionally sold by the pint). All other goods are required by law to be sold in metric units, although old quantities are retained for some goods like butter, which is sold in 454-gram (1 lb) packaging. The majority of cars sold pre-2005 feature speedometers with miles per hour. The imperial system is still often used in everyday conversation, especially in the terms of height and weight, particularly by the older generation.
Other countries
Some imperial measurements remain in limited use in IndiaMetrication in India
Metrication or metrification is the process of converting to the metric system based on the International System of Units . India's conversion to the metric system occurred in stages between 1955 and 1962...
, Malaysia and Hong Kong
Hong Kong units of measurement
Hong Kong units of measurement is based on the measurement units of Chinese of Qing Empire, British Imperial and metric. Both British Imperial and Chinese units were used until recently. In 1976 Hong Kong started the conversion to the metric system. This has now been almost completed with almost...
. Real estate agents continue to use acres and square feet to describe area in conjunction with hectares and square metres. Measurements in feet and inches, especially for a person's height, are frequently met in conversation and non-governmental publications. In India, inches, feet, yards and degrees Fahrenheit are often used in conjunction with their metric counterparts, while area is measured in acres exclusively (hectares are only used in government documents).
Towns and villages in Malaysia with no proper names had adopted the Malay
Malay language
Malay is a major language of the Austronesian family. It is the official language of Malaysia , Indonesia , Brunei and Singapore...
word batu (meaning "rock") to indicate their locations along a main road before the use of metric system (for example, batu enam means "6th mile" or "mile 6"). Many of their names remain unchanged even after the adoption of the metric system for distance in the country.
Petrol is still sold by the imperial gallon in Anguilla, Antigua and Barbuda, Belize, Burma, the Cayman Islands, Ecuador, Grenada, Guyana, Sierra Leone and the United Arab Emirates. The United Arab Emirates Cabinet in 2009 issued the Decree No. (270 / 3) specifying that from 1 January 2010 the new unit sale price for petrol will be the litre and not the gallon. This in line with the UAE Cabinet Decision No. 31 of 2006 on the national system of measurement, which mandates the use of International System of units (SI) as a basis for the legal units of measurement in the country. Sierra Leone switched to selling fuel by the litre in May 2011. Antigua and Barbuda will convert to litres before 2015.
See also
- Board footBoard footThe board-foot is a specialized unit of measure for the volume of lumber in the United States and Canada. It is the volume of a one-foot length of a board one foot wide and one inch thick....
- Comparison of the imperial and US customary measurement systems
- Conversion of unitsConversion of unitsConversion of units is the conversion between different units of measurement for the same quantity, typically through multiplicative conversion factors.- Process :...
- Cooking weights and measuresCooking weights and measuresIn recipes, quantities of ingredients may be specified by mass, by volume, or by count.For most of history, most cookbooks did not specify quantities precisely, instead talking of "a nice leg of spring lamb", a "cupful" of lentils, a piece of butter "the size of a walnut", and "sufficient" salt...
- Cord (volume)
- History of measurementHistory of measurementUnits of measurement were among the earliest tools invented by humans. Primitive societies needed rudimentary measures for numerous tasks such as: constructing dwellings of an appropriate size and shape, fashioning clothing, or bartering food or raw materials....
- MetricationMetricationMetrication refers to the introduction and use of the SI metric system, the international standard for physical measurements. This has involved a long process of independent and systematic conversions of countries from various local systems of weights and measures. Metrication began in France in...
- Systems of measurementSystems of measurementA system of measurement is a set of units which can be used to specify anything which can be measured and were historically important, regulated and defined because of trade and internal commerce...
- Unit of measurement