Weights and measures - Doryokou

Japanese: 度量衡 - どりょうこう

It refers to the units, standards, and conventions and systems for measuring length, area, volume, and mass. It was once considered to be the English equivalent of "weights and measures," but nowadays it is considered to be the English equivalent of "metrology." The International Vocabulary of Metrology (VIM) defines metrology in a broad sense as "the science of measurement and its scientific applications."

[Koizumi Kesakatsu and Imai Hidetaka]

The origin of the word weights and measures

The Lulizhi section of the Book of Han states, "Degrees are fen, sun, shaku, jo, and yin. These are the means of measuring long and short. They originally originated from the length of the Yellow Bell." Fen, sun, shaku, jo, and yin are units, and the Yellow Bell is the standard on which these units are based. Shaku originally originated from the width of the hand, but the size of a human hand is not constant. Therefore, a standard was established by taking advantage of the fact that flutes with a fixed tune have a fixed length. The Yellow Bell is the standard tone of the twelve-tone tuning system of ancient China, and the length of a flute that produces this tune is set to 9 sun, or 90 minutes. 10 sun is shaku, 10 shaku is jo, and 10 jo is yin.

It continues, "The quantities are yaku, go, sho, to, and koku. These are the means of measuring quantity. It originated from the Huangzhong yaku (tube). Its volume is adjusted according to degrees. It is filled with 1200 grains of average-sized millet (black millet, sorghum) grown in the north. When the level is adjusted using well water, the volume is 1 yaku. Two yakus together make 1 go, and five quantities are determined: 1 sho for 10 go, 1 sho for 1 tou, and 10 tou for 1 koku." The standard unit of volume is also the Huangzhong tube. A yaku means a bamboo tube, and the volume of the Huangzhong bamboo tube is 1 yaku, but it was too small so two were combined to make go.

It continues, "Ken is Shu, Ryo, Kin, Kin, and Seki, and when measuring things, a balance is used to determine the weight of something by setting it horizontally. It originally came from the weight according to the amount of the Yellow Bell. One kyo holds 1,200 pieces of sorghum, which weighs 12 shu. Two of these together make ryo. 24 shu is ryo. 16 ryo is 1 jin, 30 jin is 1 kun, and 4 kun is 1 koku." The 1,200 grains of sorghum that fill the bamboo tube of the Yellow Bell were used as the standard for mass. To measure mass, you need a ken, or weight, and a balance, or scale. The word 'ken' comes from 'kubiki' (a wooden pole or a yoke), and has evolved to become 'hakura' (a measuring rod).

The above is the origin of the word, but weights and scales are also called measurements and statutes. The contents of the "Book of Han" set the standard for China's measurement system, and show that it was established in the Former Han Dynasty. The word "weight" or "weight" is now considered to be the same quantity as "force," and "weight" is considered to be the measurement of mass. In English, it is called "mass," but "weight" is commonly used.

[Koizumi Kesakatsu]

Changes in units

China

In ancient China, the measurement of weights and measures started with parts of the human body, such as the hand width, and the scale started with millet, which was the staple food, but in the Han dynasty, a system was established based on the Huangzhong tube as the standard. This system was passed down to later generations, but the size of the unit of measurement changed and the combination of the scale unit changed, and it was almost stable by the Tang dynasty. The systems unique to Korea and Japan were introduced along with the technology during this process of change.

[1] Sizes of units of measurement in the Han Dynasty Based on surviving artifacts and documents, it is believed that they were as follows:

(1) Length: 1 shaku (approximately 23.3 centimeters in the Western Han Dynasty and 23.4 centimeters in the Later Han Dynasty), 1 zōei shaku (approximately 30 centimeters).

(2) Area Generally, area was expressed as a unit by the length of the sides. The basic unit was the fu (ho), which was 6 shaku square, and the fu began as the length of 2 human steps. A bo (ri) was 240 bu (1440 shaku square), and a ri (sato) was 300 bu (1800 shaku square). The length of one side was also used as a unit of distance.

(3) Volume: 1 sho (approximately 198 milliliters).

(4) Mass: 1 ryo (approximately 14.16 grams), 1 shu (1/24 of a ryo), 1 jin (16 ryo), 1 kun (30 jin = 480 ryo), 1 shoku (4 kun = 1,920 ryo).

[2] Size of units in the Tang Dynasty
(1) Length: 1 small shaku (about 24.6 centimeters), 1 large shaku (about 30 centimeters).

(2) Area: 1 bu (25 square shaku = approximately 2.25 square meters), 1 mu (240 bu).

(3) Volume: 1 small sho (approximately 238 milliliters), 1 large sho (approximately 713 milliliters).

(4) Mass: 1 jin (16 small ryo = approximately 198.94 grams, 16 large ryo = approximately 596.82 grams).

[Koizumi Kesakatsu]

Japan

This Tang system was adopted in the Taiho Ritsuryo (702), but the Goryeo shaku, which was two sun longer than the Tang taishaku, had been used before that, and some say that the taishaku in the Ritsuryo was the Goryeo shaku and the koshaku was the Tang taishaku. The Shoku Nihongi (Chronicles of Japan), which states that "On the third day of the Taiho era, on the day of the pig in the third month, the first units of measurement were distributed throughout the world," lists the Tang units of measurement in the miscellaneous orders, but the Ryo no Gige (Chronicles of Japan) states that "All those who measure land, silver, copper, and grain should use the taishaku, and all other government and private use should use the koshaku," so it is believed that the taishaku, taishaku, and tairyo were generally used for land, grain, and other important items in daily life. For this reason, the koshaku soon disappeared. The Japanese shaku of today is a slight extension of the taishaku in the Ritsuryo. Since the measuring tool was a tool for collecting taxes, the size of the masu changed greatly and it is difficult to trace the changes, but it is estimated that a large masu under the Ritsuryo Code was about 4 to 6 go in size, the equivalent of today's size.

A system of weights and measures always involves the inspection and regulation of weights and measures. In the section on Sekishirei in the Ritsuryo Gikai, it is written, "In general, all official and private weights and measures should be proofread at the Ministry of Finance every February. Those who are absent from Kyoto should go to their local provincial governor for proofreading, and only then will they be allowed to use them." In order to carry out this inspection, the Ministry of Finance and provincial governors were issued with "tameshi," or standard instruments. "Tameshi" means a tool for "testing." The Ritsuryo Gikai states, "In general, all government offices that use measurement authority are provided with standard instruments. All such instruments are made of copper." Standard instruments are made of copper because it is a material that does not rust or change over time.

This system of determining units of weights and measures, issuing standard instruments to government offices, and inspecting weights and measures has been common throughout the East and West since ancient times. However, this system also disappeared with the decline of the Ritsuryo system, and was finally unified with the installation of measuring tables and balance tables by the Edo Shogunate, but the actual situation had changed considerably. Measures did not have bases, but kanejaku, which is close to the modern shaku, were generally used, and for dressmaking there were gofuku shaku (1.2 shaku) and kujira shaku (1.25 shaku). The kanejaku was scaled in decimal units of bun, sun, and jo, and a separate unit of 6 shaku was used for land and buildings. 60 ken was 1 cho, and 36 cho was generally 1 ri, but the unit of ri varied greatly depending on the region. The unit of land area is 6 shaku squared bu (tsubo), 1/10 of which is go, 1/100 of which is shaku, 30 bu is se, 300 bu is tan (tan), and 3000 bu is cho. Under the Ritsuryo Code, a dan was 360 bu, but this was changed during the Taiko land survey. Volume was measured as 1 sho, which was 64,827 (64,827, so-called "mushiyafuna") cubes of 4.9 sun square and 2.7 sun deep, and was used in decimal units of shaku, go, to, and seki. The weight of Kaiyuan Tongbao coins was changed to 1 sen (momme) in the Song Dynasty, and the weight of 1,000 sen and 160 sen were used together. The weight of 10 momme was also used, but it eventually fell out of use and remained as a unit of currency.

[Koizumi Kesakatsu]

Changes in the enactment since the Meiji period

The Meiji government enacted the Weights and Measures Control Ordinance in 1875 (Meiji 8), which set up a system of contractors for the manufacture of the three weights and measures, and had local governments carry out inspections. This ordinance did not specify the units, but the shaku was the so-called compromise shaku (actually the shaku used for the masu of the masu seat) that Ino Tadataka created by averaging the Kyoho shaku and Matashiro shaku when he was surveying the whole country, and was approved by the Dajokan in 1874. As a result, this was 10/33 of a meter, and was established as the current shaku. The weight was the same as in the Edo period, but the conversion value to grams was 3.756521 grams, as stated in the 1871 New Currency Ordinance. This value was changed to the current 3.75 grams when the Weights and Measures Act was enacted in 1891, when the kan was set at 1/4 of a kilogram.

In 1885, Japan joined the Metre Convention and was able to obtain the prototypes of the meter and kilogram, leading to the enactment of the Weights and Measures Act in 1891. This act first defined shaku and kan as basic units based on the meter and kilogram prototypes, and based on this, established units of degree, land area, amount, and balance, and established the kujira shaku for use only with cloth. The structure of these units is not very different from that of the Edo period. Then, in Article 5, these shaku-kanho units and their equivalent values in the metric system were listed, making metric weights and measures legal. The term shaku-kanho was created at this time in reference to the metric system.

The types, shapes, and materials of measurement instruments were to be regulated by Imperial Ordinance (equivalent to today's Cabinet Orders), and their structures were regulated by regulations. The limits of instrument error, or tolerances, were also stipulated for the first time. Japan's measurement systems were now fully organized, but a unique licensing system was established for the manufacture, repair, and sale of measurement instruments. This system became a permit system when the Weights and Measures Act was revised to the Measurement Act in 1951 (Showa 26), and then a registration system in 1966, which remains in place to this day.

[Koizumi Kesakatsu]

Changes in the content of weights and measures

In both the East and the West, weights and measures refer to customs and systems that regulate units for measuring length, area, volume, and mass, and inspect and regulate weights and measures. However, with the development of science and technology, the types of quantities handled have increased. Therefore, those necessary for maintaining order in commercial transactions and measurements were incorporated into the system, and the content of weights and measures changed. In Japan, the Weights and Measures Act was revised in 1919 (Taisho 8) to add megadynes for force, bars for pressure, joules for work, kilowatts for power, density (density of water at 4°C at 1 atmosphere), and degrees for temperature, which were called "units of measurement." The instruments for measuring these quantities were added as measuring instruments, but the name of the Weights and Measures Act remained the same.

In 1951, the Weights and Measures Act was revised to include 33 types of quantities of physical phenomena used in transactions and certification, excluding electromagnetic quantities defined in the Electrical Measurement Act. The name was changed to the Measurement Act, and all corresponding measuring instruments were included. The manufacturing and repair businesses of these instruments were made licensed, and sales businesses were made registration-based. Since then, the Measurement Act has been revised many times, especially in 1966, when the Electrical Measurement Act was integrated and the International System of Units (SI) was introduced to the unit system. During this time, the metric system was completed for general commercial transactions at the end of 1958, and the metric system for land and building-related matters was completed on March 31, 1966. Then, in 1993, a revision was made to unify all legal measurement units into the International System of Units, and some units that had previously conflicted with the International System of Units were gradually replaced.

[Koizumi Kesakatsu]

Measuring instruments subject to the Measurement Law

As of 1999, the Measurement Act lists 72 types of quantities for the state of physical phenomena. For details, please refer to the "Instruments" section.

In addition, the number of measuring instruments - instruments, machines, and devices for measuring quantities - was significantly reduced by amendments in 1966 and 1993, and the following 18 types of measuring instruments are now subject to regulation (as of 1999).

(1) Length meter (2) Mass meter (3) Thermometer (4) Area meter (5) Volume meter (6) Flow rate meter (7) Calorimeter (8) Flow meter (9) Density hydrometer (10) Concentration meter (11) Watt-hour meter (12) Maximum demand watt-hour meter (13) Var-hour meter (14) Illuminance meter (15) Pressure meter (16) Sound level meter (17) Vibration level meter (18) Hydrometer type specific gravity meter.

Among these types of instruments, those rarely used for transactions or certification, and special instruments that are produced in small numbers are excluded by government ordinance. Manufacturers of the measuring instruments listed here must be registered with the Minister of Economy, Trade and Industry, repairers must be registered with the prefectural governor, and those engaged in the business of selling specific types of instruments specified by government ordinance must be registered with the prefectural governor.

Furthermore, when these measuring instruments are used for transactions or certification, they are generally required to undergo inspection, with the exception of those specified by government ordinance. The types of instruments that are actually inspected include commercial scales, gas, water, electricity, gasoline meters, thermometers, blood pressure monitors, etc. Measuring instruments that pass inspection are affixed with an inspection seal. Furthermore, commercial scales and other instruments in use are inspected at regular intervals. This is called periodic inspection. Furthermore, the Measurement Act also contains provisions to ensure the accuracy of the weight of packaged goods.

Such weights and measures or metrology systems are established by each country, although there are some differences in the structure and content. In order to unify such systems and regulations on measuring instruments internationally, the International Organization for Legal Metrology (OIML) was established in 1955, and the internationalization of various regulations has been promoted.

[Koizumi Kesakatsu]

"A Study of Weights and Measures in Japan, Volumes 1 and 2, by Kariya Ekisai (1927, Japanese Classics Collection Publishing Society)" ▽ "A History of Weights and Measures, by Koizumi Kesakatsu (1961, Corona Publishing) " ▽ "A Cultural History of Things and Humans 22: Rulers, by Koizumi Kesakatsu (1977, Hosei University Press)" ▽ "A Cultural History of Things and Humans 36: Measures, by Koizumi Kesakatsu (1980, Hosei University Press)" ▽ "A Cultural History of Things and Humans 48: Scales, by Koizumi Kesakatsu (1982, Hosei University Press)" ▽ "Guidelines for the Transition to the International System of Units (SI)" (1997), edited and published by the Japan Gas Association

Chinese historical units
©Shogakukan ">

Chinese historical units

Japanese yen conversion table
©Shogakukan ">

Japanese yen conversion table

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

Japanese:

長さ、面積、体積および質量の単位、標準、ならびにこれらの計量器について定められた慣習や制度をいう。かつては英語でweights and measuresにあたるとされていたが、最近では、英語のmetrologyに相当する。国際計量用語集（VIM）ではmetrologyは「測定の科学とその科学の応用」と広い意味に定義されている。

［小泉袈裟勝・今井秀孝］

度量衡の語源

『漢書』律歴志に「度は分、寸、尺、丈、引(いん)である。これが長短を計る手だてである。もと黄鐘(こうしょう)の長さにおこる」とある。分、寸、尺、丈、引は単位で、黄鐘はこれらの単位の基礎となる標準standardである。尺はもともと手幅が起源であるが、人間の手の大きさは一定しない。そこで、定まった音律の笛は一定の長さをもつということを利用して標準を定めたのである。黄鐘は古代中国の十二音律の基準音で、この音律を出す笛の長さを9寸、90分とした。そして10寸が尺、10尺が丈、10丈が引である。

　これに続いて「量は龠(やく)、合(ごう)、升(しょう)、斗(と)、斛(こく)である。これが量の多少を計る手だてである。もと黄鐘の龠（管）におこる。度によってその容量を正す。北方に産する平均的な大きさの秬黍(きょしょ)（クロキビ、コウリャン）1200粒で満つる。井戸水を用い水準を正したときの容量が1龠である。龠を二つあわせて1合とし、10合を1升、10升を1斗、10斗を1斛として五つの量が定まる」とある。体積の単位も標準は黄鐘管である。龠は竹の管の意で、黄鐘竹管の体積が1龠であるが、小さすぎるので二つあわせて合としたということである。

　さらに続いて「権(けん)は銖(しゅ)、両(りょう)、斤(きん)、鈞(きん)、石(せき)であり、物を計るに衡を水平にして軽重を知るものである。もと黄鐘の量に応じる重さにおこる。1龠には1200の秬黍が入り、この重さが12銖である。これを二つあわせて両とする。24銖が両である。16両を1斤とし、30斤を1鈞、4鈞を1石とする」とある。黄鐘竹管を満たす1200粒の秬黍を質量の標準としたわけである。質量を計るには権すなわち分銅と衡すなわち天秤(てんびん)がいる。衡はくびき（首木・軛）に由来し、転じて秤(はかり)ざおとなった。

　以上が語源であるが、度量衡はまた度量権衡ともいわれる。この『漢書』の内容は中国の計量制度の基準をなし、それが前漢において確立したことを示している。なお重さまたは重量という語は、今日では力と同じ量とされ、衡は質量の計量のこととされている。英語ではmassであるが、一般には重量weightが慣用されている。

［小泉袈裟勝］

単位の変遷

中国

古代中国の度量衡は、度量については手幅など人の身体の部分に始まり、衡は主食であったキビに始まったが、漢代に黄鐘管を標準とする体系に整えられた。この制度は後代まで引き継がれたが、度量の単位の大きさは変化し、衡の単位は組合せが変わり、唐の時代に至ってほぼ安定した。朝鮮や日本固有の制度は、この変化の過程で技術とともに渡来したものである。

〔1〕漢代の単位の大きさ　残存遺物や文献などから次のようなものであったとされている。

(1)長さ　1尺（前漢約23.3センチメートル、後漢(ごかん)約23.4センチメートル）、1造営尺（約30センチメートル）。

(2)面積　一般に辺の長さで面積を表し、単位とした。基本的な単位は歩(ふ／ほ)で6尺四方、歩は人の足で2歩(ほ)の長さに始まる。畝(ぼう)は240歩（1440尺平方）、里(り)は300歩（1800尺平方）。この1辺の長さが距離の単位にも使われた。

(3)体積　1升（約198ミリリットル）。

(4)質量　1両（約14.16グラム）、1銖（24分の1両）、1斤（16両）、1鈞（30斤＝480両）、1石（4鈞＝1920両）。

〔2〕唐代の単位の大きさ
(1)長さ　1小尺（約24.6センチメートル）、1大尺（約30センチメートル）。

(2)面積　1歩（25平方大尺＝約2.25平方メートル）、1畝（240歩）。

(3)体積　1小升（約238ミリリットル）、1大升（約713ミリリットル）。

(4)質量　1斤（16小両＝約198.94グラム、16大両＝約596.82グラム）。

［小泉袈裟勝］

日本

この唐の制度が大宝律令(たいほうりつりょう)（702）に採用されたのであるが、尺についてはこれ以前に唐大尺より2寸長い高麗尺(こまじゃく)が用いられており、律令の大尺は高麗尺、小尺が唐大尺だという説もある。『続日本紀(しょくにほんぎ)』に「大宝二年三月乙亥(きのとい)、始めて度量を天下に頒(わか)つ」とあり、雑令に度量衡とも唐制の単位をあげているが、『令義解(りょうのぎげ)』に「およそ地を度(はか)り、銀銅穀を量る者は皆大を用いよ、このほか官私ことごとく小を用いよ」とあることから、土地や穀物など日常主要なものは大尺、大升、大両が一般に用いられたと思われる。このため小のほうはまもなく消滅する。今日の日本の尺はこの律令の大尺がわずかに伸びたものである。升は枡(ます)が徴税の道具であったため変化が大きく、変化の跡づけは困難であるが、律令の大升はいまの4合から6合程度であったと推定される。

　度量衡の制度にはかならず度量衡器の検定と取締りがある。『令義解』関市令の部に「およそ官私権衡度量は毎年二月大蔵省に詣(まい)り平校せよ。京に不在の者は所在の国司に詣(もう)でて平校し、然(しか)る後用ゆるを許す」とある。この検定を行うため大蔵省および国司には「様(ためし)」つまり基準器を交付した。様は「ためす」道具の意味である。『令義解』に「およそ度量権を用いる官司には皆様を給(たま)う。その様は皆銅をもって作る」とある。基準器を銅でつくるのは、それが錆(さ)びたり時間的な変化をしない材料だからである。

　このように度量衡の単位を定め、基準器を官庁に交付して、度量衡器の検定を行うという制度は、古来東西を通じて共通したものである。ただこの制度も律令制の衰退とともに実態がなくなり、江戸幕府による枡座、秤座(はかりざ)の設置によってようやく統一されるが、実態はかなり変わっていた。尺度には座は設けられなかったが、一般には現行の尺に近い曲尺(かねじゃく)が用いられ、裁衣用に呉服尺（1.2尺）と鯨(くじら)尺（1.25尺）があった。曲尺の進法は十進的に分、寸、丈で、別に6尺の間(けん)が土地・建物用に用いられた。60間が1町で、36町が一般に1里であるが、里は地方によって大きく異なっていた。地積は6尺平方の歩（坪）が単位で、その10分の1が合、100分の1が勺で、30歩が畝(せ)、300歩が段（反）、3000歩が町である。律令では360歩が段であったが、太閤(たいこう)検地の際に改められた。体積は曲尺で方4.9寸、深さ2.7寸の積6万4827（六四八二七、いわゆる「むしやふな」）立方分を1升とし、それを基本として十進的に勺、合、斗、石とした。衡は律令の銖がなくなり、開元通宝銭の質量を1銭（匁）とする宋(そう)制に変わり、また1000銭の貫と160銭の斤が併用され、10匁の両も用いられたが、やがて用いられなくなり貨幣の単位として残った。

［小泉袈裟勝］

明治以降の制定の変遷

明治政府は1875年（明治8）度量衡取締条例を制定し、度量衡三器とも製作請負人制度として、検査は地方庁に行わせた。この条例には単位の規定はないが、尺は、伊能忠敬(ただたか)が全国測量にあたり、享保(きょうほう)尺と又四郎尺を平均してつくったといういわゆる折衷尺（実際は枡座の枡に用いられた尺）を1874年太政官(だじょうかん)の認可を得て採用した。これが結果として33分の10メートルにあたり、現行の尺として一定した。衡は江戸時代のものと異ならないが、グラムとの換算値には1871年新貨条例に記載された3.756521グラムが採用されている。この値は1891年度量衡法の制定にあたり、貫をキログラムの4分の15と定めたことにより、現行の3.75グラムに変わった。

　1885年日本はメートル条約に加盟し、メートル原器およびキログラム原器を入手できたため、1891年度量衡法を制定した。この法律は、まず基本単位として尺および貫をメートルおよびキログラム原器によって定義し、これに基づいて度、地積、量、衡の単位を定め、布帛(ふはく)用に限るとして鯨尺を定めた。この単位の構成は江戸時代のものと大差はない。そして第5条で、これら尺貫法の単位とメートル法の換算値を掲げ、メートル法度量衡を適法のものとした。尺貫法ということばはこのときメートル法に対してできたものである。

　度量衡器の種類、形状、物質は勅令（いまの政令相当）で定めるとし、構造は規則で定めた。また初めて器差の限界つまり公差も定めている。日本の度量衡はここで初めて完全な体系に整えられたのであるが、度量衡器の製造・修理・販売の事業には独特の制度である免許制を敷いた。この制度は1951年（昭和26）度量衡法が計量法に改められたとき許可制になり、さらに1966年登録制となって今日に至っている。

［小泉袈裟勝］

度量衡の内容の変化

度量衡とは東西とも、長さ、面積、体積および質量の計量に関する単位の規制、度量衡器の検査、取締りなどを内容とする慣習や制度をいうが、科学や技術の発展に伴い、取り扱う量の種類も増加してきた。そこでこれらのうち商取引や計量の秩序維持のために必要なものは、制度のなかに取り入れてゆくことになり、度量衡の内容にも変化を生じた。日本の場合1919年（大正8）度量衡法を改正して、力のメガダイン、圧力のバール、仕事のジュール、工率のキロワット、密度（1気圧で4℃の水の密度）、温度の度を追加し、これを「計量の単位」とよんだ。そしてこれらの量の計器を計量器として追加したが、度量衡法の名称はそのままとした。

　1951年に度量衡法は大改正されて、取引や証明に用いられている物象の状態の量は、電気測定法に定められている電磁気量を除いて網羅され33種となった。名称も計量法と改められ、対応する計量器もすべて対象とされるとともに、これらの製造・修理の事業は許可制、販売の事業は登録制となった。その後、計量法はしばしば改正され、とくに1966年に電気測定法を統合する改正によって単位制度に国際単位系（SI）が導入された。この間1958年末には一般商取引分野のメートル法化を終わり、1966年3月31日をもって土地・建物関係のメートル法化を終えている。そして1993年（平成5）には、法定計量単位をすべて国際単位系へ統一する改正が行われ、これまで国際単位系と食い違っていた一部の単位の切り替えを順次実施していくこととなった。

［小泉袈裟勝］

計量法の規制対象計量器

1999年現在の計量法にあげられている物象の状態の量は72種となっている。この内容については「計器」の項を参照されたい。

　また、量を計る器具、機械、装置である計量器については、1966年、1993年の改正で大幅に削減され、次の18器種が規制対象計量器となっている（1999年現在）。

(1)長さ計　(2)質量計　(3)温度計　(4)面積計　(5)体積計　(6)流速計　(7)熱量計　(8)流量計　(9)密度浮ひょう　(10)濃度計　(11)電力量計　(12)最大需要電力計　(13)無効電力量計　(14)照度計　(15)圧力計　(16)騒音計　(17)振動レベル計　(18)浮ひょう型比重計。

　これらの器種のうち取引や証明に使われることの少ないもの、つくられる数の少ない特殊なものなどは政令で除かれている。ここにあげられた計量器を製造する者は経済産業大臣の登録を、修理する者は都道府県知事の登録を受けなくてはならず、また政令で定められる特定の器種の販売の事業を行う者は都道府県知事の登録を受けなくてはならない。

　またこれらの計量器を取引や証明に使用する場合は、一般に検定を受けなければならないとされているが、政令で定めるものは除くとされ、実際に検定が行われている器種は、商業用の秤、ガス・水道・電気・ガソリンなどのメーター類、体温計、血圧計などである。検定に合格した計量器には検定証印が付される。また使用中の商用の秤などは一定の期間ごとに検査が行われる。これを定期検査という。さらに計量法は、包装商品の量目の正確さを確保するための規定も設けている。

　このような度量衡あるいは計量の制度は、体系や内容に多少の違いはあっても、各国が設けているものである。そこでこのような制度や計量器に対する規制などを国際的に統一するため、1955年国際法定計量機関（OIML）が設けられて、各種の規制の国際化が進められている。

［小泉袈裟勝］

『狩谷棭斎著『本朝度量衡攷　上下』（1927・日本古典全集刊行会）』▽『小泉袈裟勝著『度量衡の歴史』（1961・コロナ社）』▽『小泉袈裟勝著『ものと人間の文化史22　ものさし』（1977・法政大学出版局）』▽『小泉袈裟勝著『ものと人間の文化史36　枡（ます）』（1980・法政大学出版局）』▽『小泉袈裟勝著『ものと人間の文化史48　秤（はかり）』（1982・法政大学出版局）』▽『日本ガス協会編・刊『国際単位系（SI）への移行ガイドライン』（1997）』