It is the only SI prefix which uses a character not from the Latin alphabet. In Unicode, the symbol is represented by U+03BCμ or the legacy symbol U+00B5µ . The prefix "mc" is commonly used in healthcare or when the character "μ" is not available; for example, "mcg" commonly denotes a microgram.[2] The letter "u" is sometimes used instead of "μ" when non-Latin characters are not available.
^Prefixes adopted before 1960 already existed before SI. The introduction of the CGS system was in 1873.
Symbol encoding in character setsEdit
The official symbol for the SI prefixmicro is a Greek lowercase mu (μ).[6] For reasons stemming from its design, Unicode has two different character codes for the letter, with slightly different appearance in some fonts, although most fonts use the same glyph. The micro sign (µ) is encoded in the "Latin-1 Supplement" range identical to ISO/IEC 8859-1 (since 1987), at U+00B5 (Alt+0181),[7] residing at this code point also in DEC MCS (since 1983) and ECMA-94 (since 1985). The Greek letter (μ) is encoded in the Greek range at U+03BC (Alt+956). According to The Unicode Consortium, the Greek letter character is preferred,[8] but implementations must recognize the micro sign as well. This distinction also occurs in some legacy code pages, notably Windows-1253.
In circumstances in which only the Latin alphabet is available, ISO 2955 (since 1974,[9] withdrawn 2001[10]), DIN 66030 (since 1980[11][12]) and BS 6430 (since 1983) allow the prefix μ to be substituted by the letter u (or even U, if lowercase letters are not available), as, for example, in um for μm, or uF for μF, or in the common abbreviation UC for microcontroller (µC). Similarly, capacitor values according to the RKM code defined in IEC 60062 (since 1952) can be written as 4u7 (or 4U7) instead of 4μ7 if the Greek letter μ is not available.
Other abbreviating conventionsEdit
In some health care institutions, house rules deprecate the standard symbol for microgram, "μg", in prescribing or chart recording, because of the risk of giving an incorrect dose because of the misreading of poor handwriting.[13] The two alternatives are to abbreviate as "mcg"[13][2] or to write out "microgram" in full (see also List of abbreviations used in medical prescriptions). The alternative abbreviation may be ambiguous in rare circumstances in that mcg could also be read as a micrigram, i.e. 10−14 g; however the prefix micri is not standard, nor widely known, and is considered obsolete. This deprecation, focused on avoiding incorrect dosing in contexts where handwriting is often present, does not extend to all health-care contexts and institutions (for example, some clinical laboratories' reports adhere to it, whereas others do not[13]), and in physical sciences research, "μg" remains the sole official abbreviation.
In medical data exchange according to the Health Level 7 (HL7) standard, the μ can be replaced by u as well.[14]
^ ab"ISMP List of Error-Prone Abbreviations, Symbols, and Dose Designations: Abbreviations for Doses/Measurement Units". Recommendations. Institute for Safe Medication Practices (ISMP). 2021-02-05. from the original on 2022-12-24. Retrieved 2022-12-24. Error-Prone Abbreviations, Symbols, and Dose Designations: µg […] Intended Meaning: Microgram […] Misinterpretation: Mistaken as mg […] Best Practice: Use mcg […]
^Biology by Campbell & Reece, tenth edition. Ch. 6 "A Tour of the Cell". p. 98.
^ ab"On the extension of the range of SI prefixes". 2022-11-18. Retrieved 2023-02-05.
^ISO 2955-1974: Information processing - Representations of SI and other units for use in systems with limited character sets (1st ed.). 1974.
^"Table 2". ISO 2955-1983: lnformation processing - Representations of SI and other units for use in systems with limited character sets(PDF) (2nd ed.). 1983-05-15. Retrieved 2016-12-14. [1]
^DIN 66030: Darstellungen von Einheitennamen in Systemen mit beschränktem Schriftzeichenvorrat (in German) (1st ed.). 1980.
^"Neue Normen für die Informationsverarbeitung". Computerwoche (in German). 1981-01-09. from the original on 2016-12-14. Retrieved 2016-12-14.
^ abcBurtis, Carl A.; Ashwood, Edward R.; Bruns, David E. (2012), Tietz Textbook of Clinical Chemistry and Molecular Diagnostics (5th ed.), Elsevier Health Sciences, ISBN978-1455759422.
^"Commonly Used UCUM Codes for Healthcare Units". HL7 Deutschland e.V. 2015-11-21. from the original on 2022-10-06. Retrieved 2022-12-24.
micro, this, article, about, prefix, other, uses, micro, disambiguation, look, micro, wiktionary, free, dictionary, micro, greek, letter, italic, unit, prefix, metric, system, denoting, factor, millionth, confirmed, 1960, prefix, comes, from, greek, μικρός, mi. This article is about the SI prefix For other uses see Micro disambiguation Look up micro in Wiktionary the free dictionary Micro Greek letter m mu non italic is a unit prefix in the metric system denoting a factor of 10 6 one millionth 1 Confirmed in 1960 the prefix comes from the Greek mikros mikros meaning small It is the only SI prefix which uses a character not from the Latin alphabet In Unicode the symbol is represented by U 03BC m or the legacy symbol U 00B5 µ The prefix mc is commonly used in healthcare or when the character m is not available for example mcg commonly denotes a microgram 2 The letter u is sometimes used instead of m when non Latin characters are not available Contents 1 Examples 2 Symbol encoding in character sets 3 Other abbreviating conventions 4 See also 5 ReferencesExamples EditTypical bacteria are 1 to 10 micrometer 1 10 µm in diameter Eukaryotic cells are typically 10 to 100 micrometers in diameter 3 SI prefixesvte Prefix Base 10 Decimal Adoption nb 1 Name Symbolquetta Q 1030 1000 000 000 000 000 000 000 000 000 000 2022 4 ronna R 1027 1000 000 000 000 000 000 000 000 000yotta Y 1024 1000 000 000 000 000 000 000 000 1991zetta Z 1021 1000 000 000 000 000 000 000exa E 1018 1000 000 000 000 000 000 1975 5 peta P 1015 1000 000 000 000 000tera T 1012 1000 000 000 000 1960giga G 109 1000 000 000mega M 106 1000 000 1873kilo k 103 1000 1795hecto h 102 100deca da 101 10 100 1 deci d 10 1 0 1 1795centi c 10 2 0 01milli m 10 3 0 001micro m 10 6 0 000001 1873nano n 10 9 0 000000 001 1960pico p 10 12 0 000000 000 001femto f 10 15 0 000000 000 000 001 1964atto a 10 18 0 000000 000 000 000 001zepto z 10 21 0 000000 000 000 000 000 001 1991yocto y 10 24 0 000000 000 000 000 000 000 001ronto r 10 27 0 000000 000 000 000 000 000 000 001 2022 4 quecto q 10 30 0 000000 000 000 000 000 000 000 000 001Notes Prefixes adopted before 1960 already existed before SI The introduction of the CGS system was in 1873 Symbol encoding in character sets EditThe official symbol for the SI prefix micro is a Greek lowercase mu m 6 For reasons stemming from its design Unicode has two different character codes for the letter with slightly different appearance in some fonts although most fonts use the same glyph The micro sign µ is encoded in the Latin 1 Supplement range identical to ISO IEC 8859 1 since 1987 at U 00B5 Alt 0181 7 residing at this code point also in DEC MCS since 1983 and ECMA 94 since 1985 The Greek letter m is encoded in the Greek range at U 03BC Alt 956 According to The Unicode Consortium the Greek letter character is preferred 8 but implementations must recognize the micro sign as well This distinction also occurs in some legacy code pages notably Windows 1253 In circumstances in which only the Latin alphabet is available ISO 2955 since 1974 9 withdrawn 2001 10 DIN 66030 since 1980 11 12 and BS 6430 since 1983 allow the prefix m to be substituted by the letter a href U html title U u a or even a href U html title U U a if lowercase letters are not available as for example in um for mm or uF for mF or in the common abbreviation UC for microcontroller µC Similarly capacitor values according to the RKM code defined in IEC 60062 since 1952 can be written as 4u7 or 4U7 instead of 4m7 if the Greek letter m is not available Other abbreviating conventions EditIn some health care institutions house rules deprecate the standard symbol for microgram mg in prescribing or chart recording because of the risk of giving an incorrect dose because of the misreading of poor handwriting 13 The two alternatives are to abbreviate as mcg 13 2 or to write out microgram in full see also List of abbreviations used in medical prescriptions The alternative abbreviation may be ambiguous in rare circumstances in that mcg could also be read as a micrigram i e 10 14 g however the prefix micri is not standard nor widely known and is considered obsolete This deprecation focused on avoiding incorrect dosing in contexts where handwriting is often present does not extend to all health care contexts and institutions for example some clinical laboratories reports adhere to it whereas others do not 13 and in physical sciences research mg remains the sole official abbreviation In medical data exchange according to the Health Level 7 HL7 standard the m can be replaced by u as well 14 See also EditMicrogram Microscope Microsecond Microwave Square micrometre List of commonly used taxonomic affixesReferences Edit International Bureau of Weights and Measures 2006 The International System of Units SI PDF 8th ed ISBN 92 822 2213 6 archived PDF from the original on 2021 06 04 retrieved 2021 12 16 a b ISMP List of Error Prone Abbreviations Symbols and Dose Designations Abbreviations for Doses Measurement Units Recommendations Institute for Safe Medication Practices ISMP 2021 02 05 Archived from the original on 2022 12 24 Retrieved 2022 12 24 Error Prone Abbreviations Symbols and Dose Designations µg Intended Meaning Microgram Misinterpretation Mistaken as mg Best Practice Use mcg Biology by Campbell amp Reece tenth edition Ch 6 A Tour of the Cell p 98 a b On the extension of the range of SI prefixes 2022 11 18 Retrieved 2023 02 05 Metric SI Prefixes NIST Prefixes of the International System of Units International Bureau of Weights and Measures page visited on 9 May 2016 Unicode 1 0 1991 Unicode Technical Report 25 ISO 2955 1974 Information processing Representations of SI and other units for use in systems with limited character sets 1st ed 1974 Table 2 ISO 2955 1983 lnformation processing Representations of SI and other units for use in systems with limited character sets PDF 2nd ed 1983 05 15 Retrieved 2016 12 14 1 DIN 66030 Darstellungen von Einheitennamen in Systemen mit beschranktem Schriftzeichenvorrat in German 1st ed 1980 Neue Normen fur die Informationsverarbeitung Computerwoche in German 1981 01 09 Archived from the original on 2016 12 14 Retrieved 2016 12 14 a b c Burtis Carl A Ashwood Edward R Bruns David E 2012 Tietz Textbook of Clinical Chemistry and Molecular Diagnostics 5th ed Elsevier Health Sciences ISBN 978 1455759422 Commonly Used UCUM Codes for Healthcare Units HL7 Deutschland e V 2015 11 21 Archived from the original on 2022 10 06 Retrieved 2022 12 24 Portal nbsp Physics Retrieved from https en wikipedia org w index php title Micro amp oldid 1174625331, wikipedia, wiki, book, books, library,
