What is the diameter in mm of a human hair?

An educational, fair use website

Table of Contents Show

Definitions[edit]
Other body part measurements[edit]
See also[edit]
References[edit]
Notes[edit]
Citations[edit]
Sources[edit]
What is the diameter of a hair in MM?
What is the diameter of a human hair?
How thick is a strand of hair in MM?

Bibliographic Entry	Result (w/surrounding text)	Standardized Result
Piezo Technology. Epson (UK) Ltd.	"45 microns, 2 times smaller than the diameter of a human hair and close to the limit of resolution for the human eye"	90 μm
Denny R's Homepage. Denny & Gayle Rossbach. Palmdale, CA.	"Diameter of a human hair inches: 0.001; centimeters: 0.00254"	25.4 μm
Why Choose a Water Treatment System? Aqua-Fresh Drinking Water Systems, Inc.	"Particulate contaminants including asbestos, rust, sediment, dirt, and scale as small as 0.2 microns (1/300th diameter of a human hair)."	60 μm
Hair - Important Facts About Hair. CAQTI Cosmetics, Inc.	"Flaxen hair is the finest, from 1/1500 to 1/500 of an inch in diameter… and black hair is the coarsest, from 1/450 to 1/140 of an inch."	17–50 μm (flaxen) 56–181 μm (black)

Hair can be found all over human body, except for the palms of hands and at the soles of feet. The purpose of hair is protective: the hairs on the body keeps a person warm, nose hairs prevent dust and dirt from entering the respiratory system, and eyebrows prevent sweat from entering the eyes.

The diameter of a human hair does not have a standard value since different people have different hair structures. Your genetic makeup can cause the width of your hair to differ from that of other people. Hair color is also a big factor. Black hair is thicker than is red hair. The weather can also affect the diameter of a hair strand. As the weather gets warmer, the diameter of body hair increases. Age is another factor. Babies and young children have finer hair than adults. As a person grows up, their hair becomes thicker and stronger. Another factor is that, the closer to the root of the hair, the thicker a strand of hair would be.

In my research, I have found the diameter of human hair to range from 17 to 181 μm (millionths of a meter).

Brian Ley -- 1999

Bibliographic Entry	Result (w/surrounding text)	Standardized Result
SEM image of the week: Only their hairdresser knows for sure. Mert Keçeli, Joanne Wen, Sara Saad, Glenn Elert. Midwood Science (7 November 2011).	[see images below]	60~80 μm

Editor's Supplement -- 2011

External links to this page:

Single slit interference made easy with a strand of hair and a laser. Rebecca Messer. The Physics Teacher. Vol. 56 No. 1 (2018): 58.

A hair's breadth, or the width of human hair, is used as an informal unit of a very short length.[1] It connotes "a very small margin" or the narrowest degree in many contexts.[2][3][4][5][6][7]

Definitions[edit]

This measurement is not precise because human hair varies in diameter, ranging anywhere from 17 μm to 181 μm [millionths of a metre][8] One nominal value often chosen is 75 μm,[5] but this – like other measures based upon such highly variable natural objects, including the barleycorn[9] – is subject to a fair degree of imprecision.[5][7]

Such measures can be found in many cultures. The English "hair's breadth"[6] has a direct analogue in the formal Burmese system of Long Measure. A "tshan khyee", the smallest unit in the system, is literally a "hair's breadth". 10 "tshan khyee" form a "hnan" (a Sesamum seed), 60 (6 hnan) form a mooyau (a species of grain), and 240 (4 mooyau) form an "atheet" (literally, a "finger's breadth").[10][11]

Some formal definitions even existed in English. In several systems of English Long Measure, a "hair's breadth" has a formal definition. Samuel Maunder's Treasury of Knowledge and Library of Reference, published in 1855, states that a "hair's breadth" is one 48th of an inch (and thus one 16th of a barleycorn).[12] John Lindley's An introduction to botany, published in 1839, and William Withering' An Arrangement of British Plants, published in 1818, states that a "hair's breadth" is one 12th of a line, which is one 144th of an inch or ~176 μm (a line itself being one 12th of an inch).[13][14]

Other body part measurements[edit]

Winning a competition, such as a horse race, "by a whisker" (a short beard hair) is a narrower margin of victory than winning "by a nose."[15][16] An even narrower anatomically-based margin might be described in the idiom "by the skin of my teeth," which is typically applied to a narrow escape from impending disaster. This is roughly analogous to the idiomatic phrase "as small as the hairs on a gnat's bollock."[17] German speakers similarly use “Muggeseggele,” literally “housefly’s scrotum,” as a small unit of measurement.[18]

References[edit]

Notes[edit]

Citations[edit]

^ "Hair's breadth (hare's breath)". Grammarist. Retrieved January 27, 2015.
^ Hairs breadth. Oxford English Dictionary. Archived from the original on February 3, 2015. Retrieved January 28, 2015.
^ "Hairs breadth". Macmillan English Dictionary. Retrieved January 27, 2015.
^ "Hairs breadth". Cambridge Dictionary. Retrieved January 27, 2015.
^ a b c Smith 2002, p. 253.
^ a b Crook & Osmaston 1994, p. 133.
^ a b Johnson 1842, pp. 1257.
^ Ley, Brian (1999). Elert, Glenn (ed.). "Diameter of a human hair". The Physics Factbook. Retrieved 2018-12-08.
^ Boaz, Tilloch & Taylor 1823, p. 267.
^ Latter 1991, pp. 167.
^ Carey 1814, p. 209.
^ Maunder 1855, p. 12.
^ Lindley 1839, p. 474.
^ Withering 1818, p. 69.
^ "Win by a nose". The American Heritage® Idioms Dictionary. Houghton Mifflin Company/Dictionary.com. 2002. Retrieved January 27, 2015.
^ "By a nose". Free Dictionary. Retrieved December 30, 2016.
^ "The meaning and origin of the expression: By the skin of your teeth". The phrase finder. Retrieved January 28, 2015.
^ Sellner, Jan (9 March 2009). "Schönstes schwäbisches Wort: Großer Vorsprung für Schwabens kleinste Einheit". Stuttgarter Nachrichten (in German). Archived from the original on 27 September 2013. Retrieved 13 August 2013.

Sources[edit]

Boaz, James; Tilloch, Alexander, Editor; Taylor, Richard, Editor (1823-03-21). "On a fixed Unit of Measure". Philosophical Magazine. Vol. 61. London: Richard Taylor. p. 267.
Carey, Felix (1814). "Of Weights &c.". A grammar of the Burman language. Mission Press/Internet Archive. p. 209.
Crook, John; Osmaston, Henry (1994). "Weights and Measures". Himalayan Buddhist Villages. Delhi: Shri Jainendra Press. p. 133. ISBN 978-0862923860.
Dalzell, Tom; Victor, Terry, eds. (2013). The New Partridge Dictionary of Slang and Unconventional English. Routledge, Taylor & Francis Group. p. 1843. ISBN 9781317372523.
Dickson, Paul (1994). War Slang: Fighting Words and Phrases of Americans from the Civil War to the Gulf War. Ann Arbor: University of Michigan Press. p. 286. ISBN 0-671-75022-4.
Dickson, Paul (April 11, 2011). War Slang: American Fighting Words & Phrases Since the Civil War. p. 286. ISBN 9780486477503.
Dorson, Richard Mercer (1986). Handbook of American Folklore. Bloomington, Indiana: Indiana University Press. p. 123. ISBN 0-253-20373-2.
Hales, John (2005). Shooting Polaris a personal survey in the American West. Columbia, Missouri: University of Missouri Press. p. 45. ISBN 0-8262-1616-1.
Jillette, Pen (2004). Sock: A Novel. p. 114. ISBN 1429961317.
Johnson, Cuthbert William (1842). "Weights and Measures". The farmer's encyclopædia, and dictionary of rural affairs. London: Longman, Orme, Brown, Green, & Longmans/Internet Archive. p. 1257.
Johnson, Sterling (1995). English as a Second f*cking Language. New York: Saint Martin's Press, St. Martin's Griffin. ISBN 978-0-312-14329-9.
Latter, Thomas (1991). "Measures". A Grammar of the Language of Burmah (republished ed.). Asian Educational Services. p. 167. ISBN 9788120606937.
Lindley, John (1839). "Glossology". An introduction to botany (3rd ed.). London: Longman, Orme, Brown, Green, & Longmans. p. 474.
Maunder, Samuel (1855). "Measures of Length". Treasury of Knowledge and Library of Reference. New York: J. W. Bell. p. 12.\
McYoung, Mark Animal (1991). Fists, Wits and a Wicked Right:Surviving on the Wild Side of the Street. Boulder, Colorado: Paladin Press. p. 25.
Michaelis, David (1983). The best of friends: profiles of extraordinary friendships (Print). New York: Morrow. p. 231. ISBN 0-688-01558-1.
Morton, Mark S. (2003). The lover's tongue a merry romp through the language of love and sex (Print). Toronto Ontario: Insomniac Press. p. 134. ISBN 1-894663-51-9.
Partridge, Eric; Dalzell, Tom; Victor, Terry (2008). The Concise New Partridge Dictionary of Slang and Unconventional English (Print). London New York: Routledge. pp. 535, 1596 & 1601. ISBN 0-415-21259-6.
Raudaskoski, Heikki (January 1997). 'The Feathery Rilke Mustaches and Porky Pig Tattoo on Stomach': High and Low Pressures in Gravity's Rainbow. Postmodern Culture. Vol. 7. Retrieved January 20, 2015.
Smith, Graham T. (2002). Industrial metrology. Springer. pp. 253. ISBN 9781852335076.
Spelvin, Georgina (2008). The Devil Made Me Do It (Print). Los Angeles, California: Lulu.com, Little Red Hen Books. p. 110. ISBN 0-615-19907-0.
Withering, William (1818). "Botanical Terms". An Arrangement of British Plants. Vol. 1 (6th ed.). London: Longman & Co., Robert Scholey, et al. p. 69.

What is the diameter of a hair in MM?

Europeans consider hair with a diameter of 0.04 to 0.06 mm as thin, hair with a diameter between 0.06 and 0.08 mm as normal, and hair with a diameter between 0.08 and 0.1 mm as thick. By comparison with European hair, Asian hair is significantly thicker. The average diameter of Asian hair is 0.08 to 0.12 mm.

What is the diameter of a human hair?

The width of a human hair sourced from a female elementary school student was measured by light diffraction using red and blue laser pointers. The two laser sources both provided consistent estimates of the hair diameter of approximately 50 μm.