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1 Abbreviations

1.01 Introduction

The use of abbreviations has gained greater acceptance as an increasing number of new products and organizations are identified by shorter and more easily recognizable word forms.

In addition to abbreviations in the strict sense (including the short forms of common nouns, Latin expressions and titles), this chapter contains information and recommendations regarding acronyms, initialisms, and symbols such as those for metric units, which are uniform in many languages.

1.02 General guidelines and observations

Many abbreviations will not be understood unless the term is written in full at first mention, with the abbreviation given in parentheses. Follow these general rules:

  • In general, abbreviate words only when the short form will be immediately recognized by the reader, and ensure that the same abbreviation is used elsewhere in your text to represent the word or words involved.
  • Some standard abbreviations such as i.e., AD, IQ, ESP, CBC and MP do not have to be spelled out because they are well known and in many cases occur as dictionary entries.
  • Many commonly used words that are actually abbreviations are now rarely regarded as such, including ad, fridge, phone, exam, memo, photo and math. Most such words should be avoided in formal writing, although cello and bus are exceptions to this rule.
  • Unless you are confident that the reader will know exactly what the abbreviation stands for, write the term in full at first mention, with the abbreviation following in parentheses:
    • Several government departments were amalgamated to form Public Works and Government Services Canada (PWGSC).
  • Common abbreviations often in the news need not be spelled out if the full term is rarely used or is difficult to pronounce:
    • DNA
      • deoxyribonucleic acid
    • HIV
      • human immunodeficiency virus
    • 3M
      • Minnesota Mining and Manufacturing Company
    • RCMP
      • Royal Canadian Mounted Police
  • If in doubt about the correct abbreviation, use the long form.

1.03 Periods

In recent years there has been a trend toward the omission of periods in abbreviations. This is particularly true of scientific and technical writing, but the practice has been spreading in general writing as well.

(a) Do not use periods with the following:

  • chemical symbols and mathematical abbreviations: H2O, NaCl, cos, log, tan;
  • SI symbols and units: cm, kg, L (see 1.23 The International System of Units);
  • abbreviations for points of the compass: winds NNW
    (Exception: In street addresses that are not on an envelope or package, use periods with compass point abbreviations: King St. E.);
  • the military rank abbreviations used in the Department of National Defence (see 1.07 Military abbreviations);
  • short forms of words: lab, flu, vet, stereo, typo; abbreviations or acronyms consisting exclusively of upper-case letters or ending in an upper-case letter (except those for personal names, legal references and most place names), e.g. NAFTA, PhD, YMCA, UN, GST, MiG, CTV.

(b) Use periods

  • with geographical abbreviations, e.g. B.C., P.E.I., but not for the two-character symbols recommended by Canada Post (see 1.09 Geographical names).
  • with most lower-case abbreviations, including a.m., p.m., e.g., i.e. (mph is one of the few exceptions).
  • at the end of abbreviations for single words: Mr., Jr., Ltd., misc., pp., Nos.
  • after each abbreviated word of a multiword term or phrase, where the abbreviation of each word consists of more than single initials, e.g. Rev. ed., Rt. Rev. (space required after each element in the abbreviation).
  • after initials in a person’s name:
    • Thelonius S. Monk
    • H. E. Hughes
      (space required between each period and the following initial or name)


If a sentence ends in an abbreviation taking a period, only one period is used.

For further information on spacing, see 7.02 Spacing.

1.04 Plurals

Add an s, but not an apostrophe, to form the plural of most abbreviations:

  • ADMs
  • BMWs
  • CAs
  • CRs
  • FTEs
  • GICs
  • MPs
  • PCBs
  • 747s

Use an apostrophe and s to form the plural of numerical names of aircraft ending in a single letter:

  • 727-100C’s
  • 747B’s
  • Cessna 402B’s

In cases where the resulting form would be ambiguous, add an apostrophe before the s:

  • c.o.d.’s
  • Q’s and A’s
  • SIN’s

Add an apostrophe and s to form the plural of abbreviations containing more than one period, and an s without an apostrophe, to form the plural of abbreviations with only one period. In the latter case, the s precedes the period:

  • G.M.’s
  • Gens.
  • pts.

The plurals of Mr. and Mrs. are irregular:

  • Mr.
    • Messrs.
  • Mrs.
    • Mmes.

The plural forms of the abbreviations for certain bibliographic references are different:

  • l. (line)
    • ll. (lines)
  • p. (page)
    • pp. (pages)
  • f. (and the one following)
    • ff. (and those following)
  • c., ch. (chapter)
    • c., ch. (chapters)
  • MS (manuscript)
    • MSS (manuscripts)
  • s. (section)
    • ss. (sections)
  • subs. (subsection)
    • subss. (subsections)

Note that SI/metric symbols maintain the same form for both singular and plural and are written without periods, except at the end of a sentence:

  • 1 cm
  • 5 cm, centimetres
  • 75 kg, kilograms
  • The boxer weighed only 75 kg, kilograms.

1.05 Capital letters and hyphens

In general, an abbreviation is capitalized or hyphenated if the unabbreviated word or words are so treated:

  • Lt.-Gov.
    • Lieutenant-Governor
  • MLA
    • Member of the Legislative Assembly
  • UBC
    • University of British Columbia

When an abbreviation is formed from letters most or all of which are part of a single word, it is capitalized, even though the full term is not:

  • ACTH
    • adrenocorticotrophic hormone
  • DNA
    • deoxyribonucleic acid
  • ESP
    • extrasensory perception
  • TV
    • television

See 1.16 Acronyms and initialisms for rules governing the capitalization of acronyms and initialisms.

1.06 Titles used with personal names

Use the following abbreviations for non-military titles preceding or following personal names:

  • Dr.
  • Esq.
  • Hon.
  • Jr.
  • Mr.
  • Mrs.
  • Ms.
  • Messrs.
  • Mmes.
  • Msgr.
  • Prof.
  • Rev.
  • Rt. Hon.
  • Sr.
  • St.

Use Ms. when referring to a woman unless a preference for Mrs. has been indicated. Although not an abbreviation, Ms. is written with a period, by analogy with Mr. and Mrs. Note that Miss is not an abbreviation and does not take a period.

Do not use Mr., Mrs., Ms., Dr. or Esq. with any other abbreviated title or with an abbreviation denoting an academic degree or honour:

  • Dr. Roberta Bondar or Roberta Bondar, MD


  • Ms. or Dr. Roberta Bondar, MD

  • Mr. Paul Kelly or Paul Kelly, Esq.


  • Mr. Paul Kelly, Esq.

Do not use the abbreviation Dr. and Rev. Dr. before the names of individuals who hold only honorary doctorates.

Saint is written out for names of persons revered as holy, but may be abbreviated in informal contexts and in lists and tables:

  • Saint Catherine
  • Saint Francis of Assisi
  • Saint Peter
  • Saint Theresa

St. and SS. (plural) are the abbreviations used.

Abbreviate professional and official titles only when they are used with surnames preceded by first names or initials:

  • Gen. Lewis MacKenzie but General MacKenzie
  • Dr. Irene Taguchi but Doctor Taguchi
  • Prof. A. N. Chomsky but Professor Chomsky

Note that there are spaces between each period and the following initial or name.

Even when used to address someone in correspondence, Rt. Hon., Hon. and Rev. must be preceded by the:

  • The Rt. Hon. Jean Chrétien, Prime Minister of Canada
  • The Hon. Alfonso Gagliano, Minister of Public Works and Government Services
  • The Rev. John Smith


The honorary title "the Honourable" is used before the names of members of the Canadian Privy Council, lieutenant-governors and certain other officials. The title "the Right Honourable" applies for life to the governor general, prime minister and chief justice of Canada. See Department of Canadian Heritage, Precedence of Canadian Dignitaries and Officials.

Do not abbreviate Mayor, Vice-President, Professor and Father when used with personal names.

1.07 Military abbreviations

In the following tables, the middle column gives the abbreviations used by the Department of National Defence (DND) and the Canadian Forces (CF), and the right-hand column those used in non-DND/CF writing:

Army and Air Force

Rank DND/CF writing non-DND/CF writing
General Gen Gen.
Lieutenant-General LGen Lt.-Gen.
Major-General MGen Maj.-Gen.
Brigadier-General BGen Brig.-Gen.
Colonel Col Col.
Lieutenant-Colonel LCol Lt.-Col.
Major Maj Maj.
Captain Capt Capt.
Lieutenant Lt Lieut.
Second Lieutenant 2Lt 2nd Lieut.
Officer Cadet OCdt (not abbreviated)
Chief Warrant Officer CWO (not abbreviated)
Master Warrant Officer   MWO (not abbreviated)
Warrant Officer WO (not abbreviated)
Sergeant Sgt Sgt.
Master Corporal MCpl (not abbreviated)
Corporal Cpl Cpl.
Private Pte Pte.


Rank DND/CF writing non-DND/CF writing
Admiral Adm (not abbreviated)
Vice-Admiral VAdm (not abbreviated)
Rear-Admiral RAdm (not abbreviated)
Commodore Cmdre (not abbreviated)
Captain(N) Capt(N) Capt.
Commander Cdr Cmdr.
Lieutenant-Commander LCdr Lt.-Cmdr.
Lieutenant(N) Lt(N) Lieut.
Sub-Lieutenant SLt Sub-Lieut.
Acting Sub-Lieutenant A/SLt (not abbreviated)
Naval Cadet NCdt (not abbreviated)
Chief Petty Officer,
1st Class
CPO 1 (not abbreviated)
Chief Petty Officer,
2nd Class
CPO 2 (not abbreviated)
Petty Officer,
1st Class
PO 1 (not abbreviated)
Petty Officer,
2nd Class
PO 2 (not abbreviated)
Master Seaman MS M.S.
Leading Seaman LS L.S.
Able Seaman AB A.B.
Ordinary Seaman OS O.S.

In non-DND/CF writing, the plurals of these abbreviated titles are formed by adding s to the principal element:

  • Gens.
  • Maj.-Gens.
  • Cols.

Note that at the Department of National Defence and within the Canadian Forces, the abbreviations for Retired and retired are Retd and retd (without a period).

1.08 University degrees, professional designations, military decorations, honours, awards and memberships

Give these and other distinctions in abbreviated form after the name of the bearer:

  • Marta Borowska, MABLS
  • The Rev. Edwin O’Malley, SJ
  • The Hon. John Smith, BComLLD
  • T. S. Wong, PhDFRSC

Unless all honours have to be indicated for information or protocol purposes, no more than two abbreviations need follow a person’s name—as, for example, in correspondence. Select the two highest honours of different types and list them in the following 1.08-1 order of precedence: first, distinctions conferred directly by the Crown (VC, QC, etc.); second, university degrees; and third, letters denoting membership in societies and other distinctions. Note that no periods are used.

1.09 Geographical names

The names of provinces, territories and districts may be abbreviated when they follow the name of a city, town, village or geographical feature:

  • Wawa, Ont.
  • Mount Robson, B.C.

It is not necessary to use the provincial abbreviation after the names of well-known cities such as Vancouver, Winnipeg, Toronto, Ottawa and Fredericton. However, since the same name is often shared by several places in Canada and other parts of the English-speaking world (e.g. Perth, Windsor, Hamilton), add the appropriate abbreviation in cases where doubt could arise.

The following abbreviations are used officially for the names of provinces and territories in Canada. The right-hand column lists the two-character symbols recommended by Canada Post for use with mailing addresses. For other purposes, use the traditional provincial abbreviations:

Province Traditional Canada Post
Alberta Alta. AB
British Columbia B.C. BC
Manitoba Man. MB
New Brunswick N.B. NB
Newfoundland and Labrador N.L. NL
Northwest Territories N.W.T. NT
Nova Scotia N.S. NS
Nunavut See note NU
Ontario Ont. ON
Prince Edward Island P.E.I. PE
Quebec Que. QC
Saskatchewan Sask. SK
Yukon Territory Y.T. YT


A territory known as Nunavut was established under the Statutes of Canada, Bill C-132, assented to on June 10, 1993. The Act came into force on April 1, 1999. Nunavut consists of the eastern part of the Northwest Territories. Although the traditional abbreviation has not yet been officially established, the Translation Bureau recommends Nun.

Do not abbreviate words such as County, Fort, Mount, North, Point, Island, Port and Saint used as part of a proper noun, unless the official name for the location shows the abbreviated form:

  • Port Radium
  • Fort Garry
  • Point Pelee
  • Sable Island
  • St. John’s, N.L.
  • Saint John, N.B.

For further information on the official form of geographical names, see Chapter 15 Geographical Names.

1.10 Addresses: streets and buildings; points of the compass

Streets and buildings

Words such as Street, Avenue, Place, Road, Square, Boulevard, Terrace, Drive, Court and Building are spelled out in general writing but may be abbreviated in footnotes, endnotes, sidenotes, tables and addresses. If the word forms part of a longer name, do not abbreviate it under any circumstances:

  • He worked at the Journal Building.
  • Get off at Queen Street Station.

Points of the compass

Abbreviate compass directions as follows:

  • N, compass direction
  • NE
  • S
  • SW
  • E, compass direction
  • NNW
  • W, compass direction
  • ESE

In general writing, the abbreviations NE, NW, SE and SW may be used to denote town and city divisions, but the words north, south, east and west should always be spelled out:

  • NW Toronto
  • Ottawa east

In general writing, abbreviated compass directions in street addresses are followed by a period:

  • 75 Booth St., Street N.


On pieces of mail, abbreviated compass directions are not followed by a period.

Do not abbreviate words such as East, West, Southeast, Northwest when they appear before a street name:

  • 150 East 52nd Street
  • 111 Southeast Central Park Avenue

1.11 Latitude and longitude

Do not abbreviate the words latitude and longitude when used alone or in ordinary prose:

  • What is the latitude of the Tropic of Cancer?
  • The wreck was found at 36°7’25’’ north latitude and 15°24’00’’ west longitude.

In technical work and when lists of co-ordinates are given, use the abbreviations lat. and long.:

  • lat. 42°15’30’’ N, compass direction
  • lat. 18°40’16’’ S
  • long. 89°17’45’’ W, compass direction
  • long. 20°19’22’’ E, compass direction

1.12 Parts of a book or document

Capitalize, but do not abbreviate, parts of a document when followed by a number or letter, e.g. Part 4, Table 14, Appendix C.

Smaller subdivisions such as paragraph, line, page and verse are also written in full but are not capitalized except in main headings. See 4.30 Parts of a book or document for further treatment of these points.

In footnotes, endnotes, bibliographies and indexes, words referring to parts of a publication should, in the interest of conciseness, be abbreviated:

  • abr.
    • abridged
  • bk., bks.
    • book(s)
  • bull.
    • bulletin
  • c., ch.
    • chapter(s)
  • ed., eds.
    • edition(s)
  • fig.
    • figure
  • fwd.
    • foreword
  • jour.
    • journal
  • mag.
    • magazine
  • pt., pts.
    • part(s)
  • ser.
    • series
  • supp.
    • supplement
  • vol., vols.
    • volume(s)

1.13 Latin terms

Beware of confusing and misusing the following abbreviations:

  • e.g.
    • for example
  • i.e.
    • that is, specifically, namely
  • etc.
    • and so on
  • et al.
    • and others
  • c., ca.
    • about, approximately
  • q.v.
    • see this word (in cross-references)

Note that the following Latin terms are not abbreviations and are never followed by a period unless they are placed at the end of a sentence:

  • ad
  • ad hoc
  • et
  • ex
  • finis
  • idem
  • in
  • infra
  • par
  • per
  • pro
  • re
  • sic
  • supra
  • via

1.14 Scientific and technical terms

There is a vast array of technical and scientific abbreviations such as those for mathematical ratios and operations, physical quantities and constants or statistical formulas and notations. Most unabridged dictionaries list such abbreviations. People working in specific disciplines should consult the appropriate manuals in their field.1

In biology, the Latin name for a genus is not abbreviated if used alone. When used with the species name, it is abbreviated as of the second reference. The species name is not abbreviated:

  • Clematis (genus)
  • Clematis virginiana (full scientific name at first reference)
  • C. virginiana (second and subsequent references)

In symbols for chemical elements, compounds and formulas, use subscript, not superscript, numerals, e.g. H2SO4, SO2.


  • Back to the note1 For a comprehensive list of such abbreviations, see ABBR: Abbreviations for Scientific and Engineering Terms.

1.15 Corporate names

The following is a list of terms often abbreviated in the names of companies or business corporations. The abbreviated forms may be freely used in footnotes, tables or bibliographic references. Avoid using Assoc., Bros., Co. and Corp. within the body of your text. Inc. and Ltd., however, may be used unless it is necessary to preserve the company’s full legal title:

  • Association
    • Assoc.
  • Brothers
    • Bros.
  • Company
    • Co.
  • Company
    • Cie. (Compagnie)
  • Corporation
    • Corp.
  • Incorporated
    • Inc.
  • Limited
    • Ltd.
  • Manufacturing
    • Mfg.
  • Manufacturers
    • Mfrs.

1.16 Acronyms and initialisms

An acronym is a pronounceable word formed from the first letters of a series of other words, such as NAFTA, NATO or GATT. An initialism is formed from the initial letters of a series of words and may not be pronounceable as a word. Examples are GST, RCMP, OECD and IDRC. The distinction is a fine one and is often overlooked in practice. Do not use periods or spacing between the letters of an acronym or initialism.

In general, acronyms are not preceded by the definite article:

  • The members of NATO rejected the idea.
  • NAFTA may be expanded to Chile and other South American countries.
  • CIDA provides grants, loans and lines of credit.

Usage varies with respect to initialisms. Those representing the names of organizations generally take the definite article, while those representing a substance, method or condition do not:

  • The CLRB is reviewing the case.
  • The unit has provided training in CPR for some time.

The correct form of the indefinite article (a or an) to use before acronyms and initialisms is determined by the consonant or vowel sound of the initial syllable, letter or number. The following examples illustrate correct English usage. Note that ease of pronunciation is the key:

  • a 3M product
  • a UFO sighting
  • an IMF loan
  • an ACTRA award
  • a QFL convention
  • a NAFTA-related issue
  • an NHL referee
  • an FM station

Use upper-case letters for acronyms or initialisms in their entirety, even if some of the component words or their parts are not normally capitalized—unless the organization concerned prefers lower case:

  • CAA
    • Canadian Automobile Association
    • Ontario Secondary School Teachers’ Federation
    • formula translation
    • Canada Institute for Scientific and Technical Information


Acronyms (not initialisms) of company names formed by using more than the initial letters of the words they represent. Usually, only the first letter of the acronym is capitalized:

  • Alcan
    • Aluminum Company of Canada
  • Inco
    • International Nickel Company
  • Nabisco
    • National Biscuit Company
  • Nortel
    • Northern Telecom Ltd.
  • Stelco
    • Steel Company of Canada Ltd.

Initialisms are always fully capitalized:

  • BBS
  • VIP
  • TSE
  • CNCP Telecommunications
  • HRDC2

Common-noun acronyms treated as fullfledged words, such as radar, laser, scuba and snafu, are written entirely in lower case without periods.

When using acronyms or initialisms such as SIN (social insurance number), PIN (personal identification number) or ISBN (International Standard Book Number) do not repeat the word number (e.g. "SIN number"). Either write the expression out in full or use the abbreviated form on its own.


  • Back to the note2 For a comprehensive list of the official acronyms and initialisms of Canadian government organizations, consult the Treasury Board’s Federal Identity Program Manual, "Titles of Federal Organizations."

1.17 Number and percentage symbols

When abbreviating the words number or numbers within the body of a text, use No. or Nos. but not the symbol #, which is generally reserved for tabular and statistical material:

  • Nos. 56–86 are missing.

Use the percent sign (%) in economic, financial, statistical or other documents where figures are abundant. In material of a general nature containing isolated references to percentages, the term is usually written out, except when used adjectivally:

  • 15 percent
  • a 15% bond (no space between numeral and %)

1.18 Ampersand

The ampersand (&) is properly used only when it forms part of a corporate name:

  • The publisher was Ginn & Co.
  • The case is being defended by Collins, Smith, White & Jones.

Do not use the ampersand in federal department legal or applied titles:

  • The Department of Public Works and Government Services
  • The Department of Indian Affairs and Northern Development


  • The Department of Public Works & Government Services
  • The Department of Indian Affairs & Northern Development

1.19 Monetary units

When it is necessary to distinguish dollar amounts in one currency from those in another, use the appropriate symbol with the figure in question:

  • The loan will be repaid in eighty instalments of Can$650 (or CAN$650) each.
  • Please enclose a cheque in the amount of US$100.

See 5.11 Money and 5.26 Other considerations for further information on monetary units.

1.20 Months and days

Always spell out the names of the months in the body of your text and in footnotes. They may be abbreviated in tabular matter, citations and references, forms and sidenotes. May, however, should not be abbreviated and June and July are shortened only in military writing.

The names of the days of the week are not abbreviated, except in tables.

1.21 Time of day and elapsed time

Present exact time as follows:

  • 11 a.m. or 11:00 a.m.
  • p.m. or 1:00 p.m.
  • 3:30 p.m.

For elapsed time, use colons, periods and no spaces:

  • 2:30:21.65 (hours, minutes, seconds, tenths, hundredths)

See 5.12 Representation of time in ordinary prose and with SI units and 5.13 Representation of time of day for additional information.

1.22 Time zones

Time zones are abbreviated when used with a specific time. Note that capitals are used, without periods. Otherwise they are written out in full:

  • 4:30 p.m. EST
  • 7:15 a.m. MST
  • Pacific standard time
  • daylight saving time

1.23 The International System of Units (SI)

The International System of Units (SI), which has replaced other metric systems and is now used in Canada and many other countries, is a decimal-based system that includes units for physical quantities.

There are seven base units in SI:

Table 1

Quantity Unit name Symbol
length metre m
mass kilogram kg
time second s
electric current ampere A
thermodynamic temperature kelvin K
amount of substance mole mol
luminous intensity candela cd

In addition, a number of derived units are used. Like the kelvin and the ampere, almost all of them are named after scientists associated with a scientific discovery. Thus, when the symbol is used, its initial letter is capitalized. When written in full, however, the unit name is in lower case, e.g. H for henry and F for farad.


Celsius takes an initial capital whether written in full or as a symbol.

The table below gives a complete list of derived units:

Table 2

Name Symbol Quantity
coulomb C quantity of electricity, electric charge
degree Celsius °C Celsius temperature3
farad F capacitance
gray Gy absorbed dose of ionizing radiation
henry H inductance
hertz Hz frequency
joule J energy, work, quantity of heat
lumen lm luminous flux
lux lx illuminance
newton N force
ohm electric resistance
pascal Pa pressure, stress
radian rad plane angle
siemens S electric conductance
sievert Sv dose equivalent of ionizing radiation
steradian sr solid angle
tesla T magnetic flux density
volt V electric potential, potential difference, electromotive force
watt W power, radiant flux
weber Wb magnetic flux
  • Back to the note3 The Celsius temperature scale (previously called Centigrade, but renamed in 1948 to avoid confusion with "centigrad," associated with the centesimal system of angular measurement), is the commonly used scale, except for certain scientific and technological purposes where the thermodynamic temperature scale is preferred. Note the use of upper-case C for Celsius.

Multiples and submultiples of base units and derived units are expressed by adding one of the prefixes from the following table directly to the unit name:

Table 3

Factor Prefix Symbol Factor Prefix Symbol
1024 yotta Y 10-1 deci d
1021 zetta Z 10-2 centi c
1018 exa E 10-3 milli m
1015 peta P 10-6 micro µ
1012 tera T 10-9 nano n
109 giga G 10-12 pico p
106 mega M 10-15 femto f
103 kilo k 10-18 atto a
102 hecto h 10-21 zepto z
101 deca da 10-24 yocto y

The prefix and unit name are always spelled as one word:

  • centimetre
  • decagram
  • hectolitre
  • kilopascal

When symbols are used, the prefix symbol and unit symbol are run together:

  • cm, centimetres
  • dag
  • hL
  • 13 kPa

Leave a full space between the quantity and the symbol:

  • 45 kg, kilograms (not 45kg, kilograms)
  • 32 °C (not 32°C)

For the sake of clarity, a hyphen may be inserted between a numeral and a symbol used adjectivally (see also 2.10 Numerals and units of measurement):

  • 35-mm film
  • 60-W bulb

Unit symbols and prefixes should always be in lower case, even when the rest of the text is in upper case:



The symbol L for litre (to distinguish it from the numeral 1) and, as mentioned above, those symbols derived from the names of scientists.

SI usage prescribes that both numeral and unit name be written in full or that both be abbreviated:

  • two metres orm

Current usage, however, accepts the use of numerals with spelled-out unit names to facilitate comprehension:

  • He ran the 100 metres in 10 seconds.

In scientific and technical writing, the preferred form is numerals with unit symbols:

  • The specific latent heat of fusion of sulphur is 38.1 K/kg.

When no specific figure is stated, write the unit name in full:

  • The means of transportation chosen depends on how many kilometres an employee has to travel to work.

Area and volume in the metric system are expressed by means of superscript numerals:

  • cm3
  • 20 m2

Do not use abbreviations such as cc or cucm for cubic centimetre (cm3), kilo for kilogram (kg), amp for ampere (A) or kph for kilometres per hour (km/h).

Because of their practical importance, the following additional units are approved for use with SI, although they do not, strictly speaking, form part of it:

Table 4

Quantity Unit name Symbol
time minute min
hour h
day d
year a
plane angle degree °
second ’’
revolution r
area hectare ha
volume litre L
mass metric ton, tonne t
linear density tex tex

Note that there is no standard symbol for week or month. These units should therefore always be spelled out in technical writing.

When a unit symbol is combined with a symbol for time, or with a derived unit implying a division, an oblique (/) separates the two:

  • 80 km/h
    • not 80 kmh or 80 kph
  • 1800 r/min
    • not 1800 rpm
  • 50 A/m
    • not 50 Am
  • 200 J/kg
    • not 200 Jkg

More detailed information on the International System of Units (SI) can be found in the National Standard of Canada, Canadian Metric Practice Guide (CAN/CSA-Z234.1-89).

1.24 The imperial system

Abbreviations for imperial weights and measures take the same form for singular and plural. Area and volume in this system are usually expressed by means of the abbreviations sq. and cu. rather than a superscript numeral. Leave a space between sq. or cu. and the abbreviation that follows it:

  • 1 ft. (foot)
  • 4 oz. (ounces)
  • 38 yd. (yards)
  • 1 mi. (mile)
  • 55 mph (miles per hour)
  • 4 gal. (gallons)
  • 100 sq. ft.
  • 20 cu. yd.
  • 17 in. (inches)

1.25 Business terms, expressions and symbols

Terms are often abbreviated for the purpose of conserving space in routine business correspondence. The following are common abbreviations used in tables and on business forms:

  • acct.
    • account
  • bal.
    • balance
  • Assn.
    • Association
  • bldg.
    • building
  • CEO
    • chief executive officer
  • dis.
    • discount
  • cont.
    • continued
  • dtd.
    • dated
  • ea.
    • each
  • fwd.
    • forward
  • FY
    • fiscal year
  • G.M.
    • general manager
  • gr.
    • gross
  • hdlg.
    • handling
  • ins.
    • insurance
  • max.
    • maximum
  • Ltd.
    • Limited
  • n.d.
    • no date
  • min.
    • minimum
  • pd.
    • paid
  • oz.
    • ounce(s)
  • recd.
    • received
  • qty.
    • quantity
  • treas.
    • treasury, treasurer
  • sec.
    • secretary
  • V.P.
    • vice-president
  • whsle.
    • wholesale

The following is a list of symbols for terms used in business correspondence and in tabular and statistical material:

  • at
    • @
  • number (before a figure)
    • #
  • and
    • &
  • pounds (after a figure)
    • #
  • percent
    • %
  • feet
  • dollar(s)
    • $
  • inches; ditto
    • ’’
  • cent(s)
    • ¢
  • paragraph
  • degree(s)
    • °
  • section
    • §
  • equals
    • =
  • by; multiplied by
    • ×

Note that a space is usually required before and after the symbols @, =, & and ×:

  • Yearwood & Boyce
  • 2 shirts @  $19.95 each


No extra space is required for upper-case abbreviations or in e-mail addresses:

  • R&D at AT&T

Note also that no space is required between figures and the symbols %, ¢, #, ’, ’’:

  • 10% deficit reduction
  • nearly 75¢ a pound
  • 43# per bag
  • 159’ × 259’ deck

Do not leave any space after the symbols $, #, ¶, § when they precede a figure:

  • less than $278
  • as mentioned in ¶21
  • package #3412
  • Refer to §1.28.