Symbols and Abbreviations

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Don’t confuse abbreviations with unit symbols, for example “sec” vs “s”

Time units: use “s” as the symbol for seconds, not sec (which is an abbreviation); h instead of hours or hr, da instead of day or days, wk instead of weeks, mo instead of months, yr instead of years

Symbols are not pluralized (kg, not kgs); kg is lower case

There are no periods after symbols (except at the end of a sentence)

The use of “M” for 1000 is obsolete; M is mega- (1 000 000); k is 1000 (and not capitalized)

Avoid multiple prefixes: pF, not µµF; nm, not mµm

For multiple symbols, use the “dot” connector between all symbols: N·m, not Nm, N-m, or N.m, and W∙m-2∙K-1 or W/(m∙K)

There should always be a space between the number and the unit symbol (10 mm, not 10mm)

Close spaces for % and °C: 25% and 25°C

Abbreviate Figure or Figures as Fig or Figs, except at the start of a sentence

Leave out periods for Fig, eg, ie, et al, etc

Leave out symbols for ranges: 10 – 20%; 10 – 20°C

Author: Frank Beall