Symbols and abbreviations, writing keys
In order to properly write the symbols and abbreviations that
frequently appear in the written media, a series of guiding keys are
- A symbol is the representation of a scientific or
technical concept, formed by letters or conventional
signs. Most have been created by standardization bodies and are internationally
valid: kg, Ag, Fe, cm, %, &, $, Å€, @,
etc. Exceptions to this normalization are some symbols of
traditional use that are valid in certain geographical areas, such
as O (Oeste), which is used in Spanish speech,
as opposed to W (West), which is the one that
prevails in the international system.
- They are not followed by an abbreviation point:
instead of 3 kg. , the appropriate is 3 kg,
without period. On the other hand, if after the symbol corresponds
to the point of end of sentence, this should not be omitted.
- They do not have a plural, so it is appropriate
to write 3 kg, instead of 3 kgs.
- When writing a figure followed by a symbol, it
is appropriate to leave an intermediate space: 3
kg, not 3kg.
- They have a standardized spelling in terms of uppercase
or lowercase letters,which must be preserved. For example,
cardinal points (S, from south; SE,
from southeast) are capitalized, as are the initials of
chemical elements (O, for oxygen; Br,
for bromine; Cl, for chlorine). The
upper and lower case of the units of measure (such as kg for
the kilogram, ha for the hectare, kW for
the kilowatt) must be preserved in all contexts, even in
texts written entirely in capital letters, since 1 mA (one
thousandth of an ampere) is not the same as 1 MA (one million
- A word can have more than one
abbreviation: for page, for example, p. and p.
- They have an abbreviated dot(a. C., pl., admón.)
or, more rarely, a bar (c/ Bailén). In abbreviations with
more than one element, a space is left after the
abbreviation period (US is written and not US) . If
the abbreviation has a flown part, the appropriate
thing is to write a period before it without
leaving a space (n.º, no nº. nor nº).
- When they have more than one letter, they generally form the pluralby
adding an s: p. > pgs. ; if they
consist of a single letter, this is usually doubled: p. > pg.