Lambda (unit)

From HandWiki
lambda
Unit systemNon-SI metric unit
Unit ofVolume
Symbolλ 
Conversions
1 λ in ...... is equal to ...
   SI base units   10−9 m3
   Units accepted for use with SI   1 μL

Lambda (written λ, in lowercase) is a non-SI unit of volume equal to 10−9 m3, 1 cubic millimetre (mm3) or 1 microlitre (μL). Introduced by the BIPM in 1880,[1] the lambda has been used in chemistry[2] and in law for measuring volume, but its use is not recommended.[3]

This use of λ parallels the pre-SI use of μ on its own for a micrometre and γ for a microgram.[4][5] Although the use of λ is deprecated, some clinical laboratories continue to use it.[6] The standard abbreviation μL for a microlitre has the disadvantage that it can be misread as mL (a unit 1000 times larger). In pharmaceutical use, no abbreviation for a microlitre is considered safe. The recommended practice is to write "microlitre" in full.[7]

References

  1. Donald Fenna (2002), A Dictionary of Weights, Measures, and Units, Oxford University Press, ISBN:0198605226, p. 153.
  2. "Units: L". University of North Carolina. https://www.unc.edu/~rowlett/units/dictL.html. Retrieved 2015-03-28. 
  3. Carl A. Burtis and David E. BrunsTietz (2014), Fundamentals of Clinical Chemistry and Molecular Diagnostics, 7th ed., Elsevier Health Sciences, ISBN:0323292062, p. 114.
  4. Lela Buckingham (2014), Fundamental Laboratory Mathematics: Required Calculations for the Medical Laboratory Professional, F. A. Davis, ISBN:0803641028, p. 48.
  5. I. P. Alimarin and M. N. Petrikova (2013), Inorganic Ultramicroanalysis, Elsevier, ISBN:1483150488, p. xiv.
  6. Barbara H. Estridge, Anna P. Reynolds, and Norma J. Walters (2000), Basic Medical Laboratory Techniques, 4th ed., Cengage Learning, ISBN:0766812065, p. 32.
  7. Chris Langley and Yvonne Perrie (2014), Maths Skills for Pharmacy: Unlocking Pharmaceutical Calculations, Oxford University Press, ISBN:019968071X, p. 55.