Alphabetical List of Units
(continued)
To convert from
to
multiply by
mile, international nautical (n mile)
mile UK nautical (n mile UK)
miles per gallon (m.p.g)
metre (m)
metre (m)
litre per kilometre (Lkrrr1)
millibar (mb)
millimetre of mercury (mmHg)
millimetre of water (4°C)
minute (angle) (...')
minute (min)
moment of inertia (Ib.ft2)
moment of inertia (Ib.in2)
moment of section, second moment of
area (ft4)
moment of section, second moment of
area (in4)
month
nautical mile, international (n mile)
nautical mile UK (n mile UK)
oersted (Oe)
ounce, avoirdupois (oz)
ounce fluid (UK) (fl.oz UK)
ounce fluid (US) (fl.oz US)
ounce, troy (oz tr)
ounce, apothecary (oz apoth)
parsec (pc)
phot(ph)
picul
pint (pt)
pint US liquid (pt US)
poise (P)
pound, avoirdupois (Ib)
poundal (pdl)
pound-force (Ibf)
pound force foot
pound force inch
pound force per foot
pound force per inch
pound force per square foot
pound force per square inch
pound per square foot
pound per square yard
quart (qt)
quart US liquid (qt US)
rad, radiation dose absorbed
roentgen (R)
second, angle (,..")
section modulus (ft3)
section modulus (in3)
short ton (sh.tn)
slug
square foot (ft2)
square foot hour °F per Btu inch
square inch (in2)
square yard (yd2)
stokes (St)
tael
tarn
tex
pascal (Pa)
pascal (Pa)
pascal (Pa)
radian (rad)
second (s)
kilogram metre squared (kg.m2)
kilogram metre squared (kg.m2)
metre4 (m4)
1.852GOQX10 3 *
1.853 184 x103
2.824 809 xn- 2
(where n equals the
number of miles)
1.000QOOX10 2 *
1.333224x10 2
9.806 65*
2.908 882 x 10-4
6.000 000 x1Q 1 *
4.214012X1Q- 2
2.926397 x1Q- 5
8.630 975 x10~ 3
metre4 (m4)
4.162 314x10- 7
second (s)
metre (m)
metre (m)
ampere per metre (A.nrr1)
kilogram (kg)
litre (L)
litre (L)
kilogram (kg)
kilogram (kg)
metre (m)
lux (Ix)
kilogram (kg)
litre (L)
litre (L)
pascal second (Pa.s)
kilogram (kg)
newton (N)
newton (N)
newton metre (N.m)
newton metre (N.m)
newton per metre (N.nrr1)
newton per metre (N.m""1)
pascal (Pa)
pascal (Pa)
kilogram per square metre (kg.m"2)
kilogram per square metre (kg.m-2)
litre (L)
litre (L)
gray (Gy)
coulomb per kilogram (C.kg-1)
radian (rad)
metre cubed (m3)
metre cubed (m3)
tonne (t)
kilogram (kg)
square metre (m2)
metre degree Celsius per watt (m. °C.W-1)
square metre (m2)
square metre (m2)
square metre per second (m2.s~1)
kilogram (kg)
kilogram (kg)
kilogram per metre (kg.m""1)
2.628 000 x10 6 *
1.852000X10 3 *
1.853 184 x103
7.957 747 x10~1
2.834 952 x10-2
2.841 306 x10~ 2
2.957 353 x10~ 2
3.110348X10- 2
3.110348X10-2
3.085 700 x10 16
1.0000QOX10 4 *
6.047 900 x101
5.682613X10-" 1
4.731 765 x10~1
1.0QOOOOX10- 1 *
4.535 924 x10~ 1
1.382 550 X10- 1
4.448 222
1.355818
1.129850X10" 1
1.459 390 x 101
1.751 269 x10 2
4.788 026 X10 2
6.894 757 x 103
4.882 427
5.424 920 X10-1
1.136523
9.463 529 x10-1
1.000000X10-2*
2.579 760 x10~ 4 *
4.848137 x10~ 6
2.831 685 x10~2
1.638 706 x10~ 5
9.071 847 x10-1
1.459390X101
9.290 304 x10~ 2 *
6.933 466
6.451 600 X10~4*
8.361 274 x10-1
1.000000X10"4*
3.779 940 x10~2
6.047 900 x101
1.000 000 x10~6*
*An asterisk indicates an exact conversion.
20
Alphabetical List of Units
(continued)
To convert from
to
multiply by
therm
therm per gallon
ton
ton force
ton force foot
ton force inch
ton force per foot
ton force per square foot
ton force per square inch
ton refrigeration (12 000 Btu per hour)
ton refrigeration (13440 Btu per hour)
ton short (sh.tn)
tonne (t)
torr
tsin
tsun (Chinese inch)
yard (yd)
year (a)
joule (J)
joule per litre (J. L"1)
tonne (t)
newton (N)
newton metre (N.m)
newton metre (N.m)
newton per metre (N.m""1)
pascal (Pa)
pascal (Pa)
watt (W)
watt (W)
tonne (t)
kilogram (kg)
pascal (Pa)
kilogram (kg)
metre (m)
metre (m)
second (s)
1.055 060x10 s *
2.320 797 X10 7
1.016047
9.964017x103
3.037032x103
2.530 860 x102
3.269 035 x104
1.072518X105
1.544426x107
3.516853x103
3.938878X103
9.071 847x10~1
1.000000X103*
1.333224x102
3.779940x10"3
3.714750x10-2
9.144 000x10~1*
3.153600x107
*An asterisk indicates an exact conversion.
3.3
CLASSIFIED LIST OF UNITS
3.3.1 Acceleration
To convert from
to
foot/second squared
free fall, standard
galileo (Gal)
inch/second squared
metre/second
metre/second
metre/second
metre/second
multiply by
squared (m/s2)
squared (m/s2)
squared (m/s2)
squared (m/s2)
3.048 000 X10- 1 *
9.806 650*
1.000000x10~2*
2.540000x10-2*
3.3.2 Area
acre
acre
are
barn
circular mil
hectare
square inch
square inch
square inch
square foot
square mile
square mile
square mile
square yard
square metre (m2)
hectare (ha)
square metre (m2)
square metre (m2)
suqare metre (m2)
square metre (m2)
suqare metre (m2)
square centimetre (cm2)
square millimetre (mm2)
square metre (m2)
hectare (ha)
square kilometre (km2)
square metre (m2)
square metre (m2)
4.046856x103
4.046 856 x10-1
1.000000x102*
1.000 000 x 10~28*
5.067 075 x10~ 10
1.000000x104*
6.451 600x10~ 4 *
6.451 600*
6.451 600 x10 2 *
9.290 304 x10~ 2 *
1.609344x10 2 *
1.609344*
2.589 988 x10 6
newton-metre
newton-metre
newton-metre
newton-metre
newton-metre
newton-metre
newton-metre
1.000000x10~7*
9.806 650*
7.061 552x10-3
1.129848X10-1
1.355818
3.037032X103
2.530860X10 2
8.361 274 x10-1
3.3.3 Bending Moment or Torque
dyne-centimetre
kilogram-force-metre
ounce-force-inch
pound-force-inch
pound-force-foot
ton-force-foot
ton-force-inch
(N.m)
(N.m)
(N.m)
(N.m)
(N.m)
(N.m)
(N.rn)
*An asterisk indicates an exact conversion.
21
3.3.4 (Bending Moment or Torque)/Length
To convert from
to
multiply by
pound-force-foot/inch
pound-force-inch/inch
newton-metre/metre (N.m/m)
newton-metre/metre (N.m/m)
5.337 866 x101
4.448 222
coulomb (C)
farad (F)
ampere (A)
volt (V)
henry (H)
ohm (Q)
farad (F)
ampere (A)
volt (V)
henry (H)
ohm (Q)
tesla (T)
tesla (T)
ampere-turn
weber (Wb)
Siemens (S)
ampere/metre (A/m)
3.600 000 X10 3 *
1.000000X109*
1.000000X101*
1.000 000 x10~ 8 *
1.000QOOX10-9*
1.00QOOOX10-9*
1.112650X10-12
3.335 600 x10-10
2.997 900 x102
8.987 554 x1011
8.987 554 X1011
1.000 000 x10~ 9 *
1.000000X10-4*
7.957 747 x10-1
1.000 OOOX10- 8 *
1.000000*
7.957 747 X10 1
kilojoule (kJ)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
megajoule (MJ)
megajoule (MJ)
joule (J)
kilojoule (kJ)
joule (J)
1,055 055
1.055 055X10 3
4.185500x103
4.186800*
1.602190x10~19
1.000000X10-7*
1.355818
4.214011X10-2
3.600 000 x10 6 *
3.600 000*
1.055060X102
4.20 x109
3.600 000*
1.000000*
watt/square metre (W/m2)
3.154588
3.3.5 Capacity (See Volume)
3.3.6 Density (See Mass/Volume)
3.3.7 Electricity and Magnetism
ampere-hour
EMU of capacitance
EMU of current
EMU of electric potential
EMU of inductance
EMU of resistance
ESU of capacitance
ESU of current
ESU of electric potential
ESU of inductance
ESU of resistance
gamma
gauss
gilbert
maxwell
mho
oersted
3.3.8 Energy (Includes Work & Heat)
British thermal unit
British thermal unit
Calorie (dieticians kilocalorie)
calorie (international table)
electron volt
erg
foot-pound-force
foot-poundal
kilowatt-hour
kilowatt-hour
therm
ton (nuclear equivalent of TNT)
watt-hour
watt-second
3.3.9 Energy/Area Time
Btu/square foot-hour
3.3.10 Flow (See Mass/Time or Volume/Time)
3.3.11 Force
dyne
kilogram-force
kilopond
kip
ounce-force (avoirdupois)
pound-force (Ibf avoirdupois)
poundal
ton force
newton
newton
newton
newton
newton
newton
newton
newton
1.000000X10-5*
9.806 650*
9.806 650*
4.448222x103
2.780139 x10-1
4.448 222
1.382550X10-1
9.947017X103
(N)
(N)
(N)
(N)
(N)
(N)
(N)
(N)
*An asterisk indicates an exact conversion.
22
3.3.12 Force/Length
To convert from
to
multiply by
pound-force/foot
pound-force/inch
ton-force/foot
newton/metre (N/m)
newton/metre (N/m)
newton/metre (N/m)
1.459390X101
1.751 268X102
3.269 035 x104
watt/metre-kelvSn (W/m.K)
watt/metre-kelvin (W/m.K)
joule/square metre (J/m2)
watt/square metre-kelvin (W/m2.K)
joule/kilogram (J/kg)
joule/kilogram-kelvin (J/kg.K)
watt/square metfe-kelvin (W/m2.K)
joule/kilogram (J/kg)
joule/kilogram-klelvin (J/kg.K)
kelvin-square metre/watt (K.m2/W)
square metre/second (m2/s)
joule per litre (J/L)
5.192204X102
1.442280X10-1
1.135653x10-4
5.678 263
2.326 000 x10 3 *
4.186800x103*
2.044175 x104
4.186800x103*
4.186800X103*
1.761 102x10~1
2.580 640x10~5*
2.320 797 x107
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
metre
1.000000x10~10*
1.495980x1011
2.011 680 x10 1 *
3.714750X10-1
1.828 800*
1.000000x10~15*
3.048 000 x10~ 1 *
2.011 680 x10 2 *
2.540 000 x10- 2 *
9.460 500 x1015
2.011 680x10-1*
1.000 000 x10~ 6 *
2.540 000X10~ 5 *
1.609344x103*
1.852000X103*
3.083 740 x1016
4.217518x10- 3
3.514598X10- 4 *
9.144000X10-1*
3.3.13 Heat
Btu in./s.ft2. °F (thermal conductivity)
Btu in./h.ft2. °F (thermal conductivity)
Btu/ft2.
Btu/h.ft2. °F (thermal conductance)
Btu/pound-mass
Btu/lb. °F (heat capacity)
Btu/s.ft2. °F
cal/g
cal/g. °C
deg. F.h.ft2/Btu (thermal resistance)
square foot/hour (thermal diffusivity)
therm per gallon
3.3.14 Length
angstrom
astronomical unit
chain
chek
fathom
fermi (femtometer)
foot
furlong
inch
light year
link
micron
mil
mile
mile, nautical (international)
parsec
pica (printer's)
point (printer's)
yard
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
3.3.15 Light
candela/square foot
candle power
footcandle
footcandle
footlambert
lambert (L)
lumen/square foot
phot
candela/square metre (cd/m2)
candela (cd)
lumen/square metre (Im/m2)
lux (Ix)
candela/square metre (cd/m2)
candela/square metre (cd/m2)
lux (Ix)
lux (Ix)
1.076391X10 1
1.019368
1.076391x101
1.076391x101
3.426 259
3.183099X10 3
1.076391x101
1.000000X104
kilogram (kg)
kilogram (kg)
kilogram (kg)
2.000 000 x10~ 4 *
6.047 900 x10~ 1
6.479 891 x10~ 5 *
3.3.16 Mass
carat (metric)
catty
grain
*An asterisk indicates an exact conversion.
23
3.3.16 Mass (continued)
To convert from
to
gram
hundredweight
mace
ounce
ounce (troy or apothecary)
picui
pound (avoidupois)
pound (troy or apothecary)
slug
tael
ton (long, 2 240 Ib.)
ton (short, 2 000 Ib.)
tonne
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
kilogram
multiply by
1.000000X10-3*
5.080 235 x101
3.779940x10-3
2.834952x10-2
3.110348x10-2
6.047 900 x101
4.535 924x10-1
3.732 417x10~1
1.459390x101
3.779940x10- 2
1.016047x103
9.071 847x102
1.000000X103*
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
(kg)
3.3.17 Mass/Area
hundredweight/acre
ounce/square yard
pound/square foot
pound/square yard
ton/acre
ton/acre
kilogram/square metre (kg/m2)
kilogram/square metre (kg/m2)
kilogram/square metre (kg/m2)
kilogram/square metre (kg/m2)
kilogram/square metre (kg/m2)
tonne/hectare (t/ha)
1.255350x10-2
3.390575x10-2
4.882 428
5.424 920 x10-1
2.510 707 x10-1
2.510707
kilogram/metre
kilogram/metre
kilogram/metre
kilogram/metre
kilogram/metre
9.000000X10-6*
1.488 164
1.785797x10 1
4.920 543 X10- 1
1.000 000 x10~ 6 *
3.3.18 Mass/Length
denier
pound/foot
pound/inch
pound/yard
tex
(kg/m)
(kg/m)
(kg/m)
(kg/m)
(kg/m)
3.3.19 Mass/Time
pound/minute
pound/second
ton (long)/hour
ton (short)/hour
kilogram/second
kilogram/second
kilogram/second
kilogram/second
(kg/s)
(kg/s)
(kg/s)
(kg/s)
7.559873X10- 3
4.535 924 x10~1
2.822 235 x10-1
2.519958X10- 1
3,3.20 Mass/Volume (includes Density and Mass/Capacity)
gram/cubic centimetre
ounce/gallon (U.K. liquid)
ounce/gallon (U.S. liquid)
ounce/cubic inch
pound/cubic foot
pound/cubic inch
pound/gallon (UK liquid)
pound/gallon (US liquid)
slug/cubic foot
ton (long)/cubic yard
ton (short)/cubic yard
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
kilogram/cubic metre
*An asterisk Indicates an exact conversion.
24
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
(kg/m3)
3
1.000 OOOxlO *
6.236 021
7.489 152
1.729 994x103
1
1.601 846 x10
2.767 990 x10 4
1
9.977 633 x10
2
1.198 264 x10
2
5.153 788 x10
1.328 939x103
3
1.186 553 X10
3.3.21 Power
To convert from
to
multiply by
Btu/hour
erg/second
foot pound force/hour
foot pound force/minute
foot pound force/second
horsepower
horsepower (boiler)
horsepower (electric)
ton refrigeration (12000 Btu/hr)
ton refrigeration (13400 Btu/hr)
watt (W)
watt (W)
watt (W)
watt (W)
watt (W)
watt (W)
watt (W)
watt (W)
watt (W)
watt (W)
2.930 711x10~1
1.000000x10~7*
3.766161 X10~4
2.259 697 x10~ 2
1.355818
7.456 999 x102
9.809 500 x103
7.460000X102*
3.516853x103
3.938 878 x103
kilopascal (kPa)
kilopascal (kPa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
kilopascal (kPa)
pascal (Pa)
megapascal (MPa)
megapascal (MPa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
pascal (Pa)
megapascal (MPa)
kilopascal
megapascal
1.013250X102
1.000000X102*
1.333224x103
9.806 380 X101
1.000000X10-1*
2.988980x103
9.806 650 X10 1 *
3.386389X10 3
2.490 820 x102
9.806 650 x101*
9.806 650*
9.806 650 *
6.894 757*
9.806650x10 3 *
1.000000X102*
1.333224x102*
9.806 65*
1.000 000*
1.000000*
1.072518X102
1.544426X10 1
degree Celsius
degree Fahrenheit
kelvin (K)
kelvin (K)
degree Fahrenheit
degree Rankine
kelvin
degree Celsius (°C)
kelvin (K)
degree Celsius (°C)
tK-t°C+273.15
tK=(t°F+459.67)/
1.8
t°C=(t°F-32)/1.8
tK-t °R/1.8
t°C-tK-273.15
second
second
second
second
second
second
second
second
8.640 000 x104
8.616409x104
3.600000x103
3.590170x103
6.000 000 x101
5.983 617X10 1
9.972 696 x10-1
3.155815x10 7
3.3.22 Pressure or Stress
atmosphere
bar
centimetre of mercury
centimetre of water
dyne/square cetimetre
foot of water
gram-force/square centimetre
inch of mercury
inch of water
kilogram-force/square centimetre
kilogram-force/square metre
kilogram-force/square millimetre
kip/square inch
metre of water (4 °C)
millibar
millimetre of mercury
millimetre of water (4 °C)
newton/square metre (N/m2)
newton/millimetre (N/mm2)
ton-force/square foot
ton-force/square inch
3.3.23 Temperature
3.3.24 Time
day
day (sidereal)
hour
hour (sidereal)
minute
minute (sidereal)
second (sidereal)
year (sidereal)
(s)
(s)
(s)
(s)
(s)
(s)
(s)
(s)
*An asterisk indicates an exact conversion.
25
3.3.25 VeSocity (includes Speed)
To convert from
to
multiply by
foot/hour
foot/minute
foot/second
inch/second
kilometre/hour
knot
mile/hour
mile/minute
mile/second
mile/hour
metre/second (m/s)
metre/second (m/s)
metre/second (m/s)
metre/second (m/s)
metre/second (m/s)
metre/second (m/s)
metre/second (m/s)
metre/second (m/s)
metre/second (m/s)
kilometre/hour (km/h)
8.466667x10~5
5.080 000 x10~ 3 *
3.048 000 x10~1*
2.540000x10-2*
2.777 778x10-1
5.144444x10~1
4.470 400 x10-1*
2.682 240 x101*
1.609344X103*
1.609 344*
pascal-second (Pa.s)
square metre/second (m2/s)
pascal-second (Pa.s)
pascal-second (Pa.s)
pascal-second (Pa.s)
pascal-second (Pa.s)
square metre/newton-second (m2/N.s)
pascal-second (Pa.s)
square metre/second (m2/s)
square metre/second (m2/s)
1.000000X10-3*
1.000000X10-6*
1.000000X10-1*
1.488164
1.488 164
4.788 026 x101
1.000000X101*
4.788 026 X10 1
9.290304X10-2*
1.000 000 x10~4*
cubic metre (m3)
cubic metre (m3)
cubic metre (m3)
cubic metre (m3)
cubic metre (m3)
cubic metre (m3)
cubic metre (m3)
cubic metre (m3)
litre (L)
litre (L)
litre (L)
litre (L)
litre (L)
litre (L)
litre (L)
cubic metre (m3)
cubic metre (m3)
cubic metre (m3)
1.233489X103
1.589 873 x10~ 1
3.523907X10- 2
2.831 685x10- 2
1.638706X10-5
4.546 090 x10-3*
3.785 412x10- 3
1.000000X10-3*
2.841 306x10- 2
2.957353x10-2
5.682 613x10~ 1
5.506 117x10~ 1
4.731 765 x10~ 1
1.136523X10- 3
9.463 529 X10- 1
1.000000x10*
2.831 685
7.645 549 X10- 1
cubic metre/second (m3/s)
cubic metre/second (m3/s)
cubic metre/second (m3/s)
cubic metre/second (m3/s)
cubic metre/day (m3/day)
cubic metre/second (m3/s)
cubic metre/second (m3/s)
litre/second (L/s)
4.719474x10-4
2.831 685x10-2
2.731 177x10-7
1.274258x10-2
4.546 090 x10-3*
5.261 678X10- 8
3.157007x10-6
1.262803X10- 3
3.3.26 Viscosity
centipoise
centistokes
poise
poundal-second/square foot
pound-mass/foot-second
pound-force-second/square foot
rhe
slug/foot-second
square foot/second
stokes
3.3.27 Volume (Includes Capacity)
acre-foot (U.S. surve)
barrel
bushel (U.S.)
cubic foot
cubic inch
gallon (U.K. liquid)
gallon (U.S. liquid)
litre
ounce (U.K. fluid)
ounce (U.S. fluid)
pint (U.K.)
pint (U.S. dry)
pint (U.S. liquid)
quart (U.K.)
quart (U.S.)
stere
ton (register)
cubic yard
3.3.28 Volume/Time (includes Flow)
cubic foot/minute
cubic foot/second
cubic inch/minute
cubic yard/minute
gallon/day
gallon/day
gallon/minute
gallon/hour
*An asterisk indicates an exact conversion.
26
3.3.29 Volume (Liquid)/Volume (Liquid-solid)
To convert from
to
multiply by
fluid ounce (U.K.)/pint (U.K.)
fluid ounce (U.K.)/gailon (U.K.)
fluid ounce (U.K.)/cubic foot
pint (U.K.)/cubic foot
pint (U.K.)/cubicyard
fluid ounce (U.S.)/pint (U.S.)
fluid ounce (U.S.)/gallon (U.S.)
fluid ounce (U.S.)/cubic foot
pint (U.S.)/cubic foot
pint (U.S.)/cubic yard
millilitre/litre (mL/L)
millilitre/litre (mL/L)
millilitre/litre (mL/L)
millilitre/litre (mL/L)
litre/cubic metre (L/m3)
mi Hi litre/litre (mL/L)
millilitre/litre (mL/L)
millilitre/litre (mL/L)
millilitre/litre (mL/L)
litre/cubic metre
5.000 000 X10-2*
6.250 000*
1.003 398
2.006 795 x101
7.432 575 X10~ 1
6.250 000 X10 1 *
7.812500*
1.044 379
2.207167 X101
8.174691X10"1
*An asterisk indicates an exact conversion.
3.4 QUANTITIES
Quantity
Unit Symbol Unit Name
Typical Applications
absorption, moisture
mg/cm2
milligram per square
centimetre
Wire and cable insulation.
absorption, tensile
energy
J/m2
joule per square metre
Paper.
acceleration, angular
rad/s2
r/s2
radian per second squared
revolution per second squared
Engineering calculations;
mechanical equipment.
acceleration, linear
m/s2
metre per second squared
Vehicles; mechanical equipment;
kinematics; calculation of dynamic
forces; exploration geophysics.
cm/s2
centimetre per second
squared
Soil dynamics.
|jm/s2
micrometre per second
squared
Gravitational acceleration anomaly
(geophysics; gravity and magnetic
surveys).
adhesion
kN/m
kilonewton per metre
Ply in conveyor belt
admittance,
electric
mS
MS
millisiemens
microsiemens
Electric circuits
and components.
altitude
m
metre
Aircraft; meteorology.
amplitude
mm
millimetre
Vibration; waveform.
angle, plane
rad
radian
Engineering and scientific calculations;
phase relationships; drill string rotation
in drilling mechanics.
degree
Degree and decimal degree are used in:
machine design; modulating control
motor stroke; bore deflection and pin
angle of downhole equipment in drilling
mechanics; wave phase relationships;
angle of entrance of ship hull.
minute
Degree, minute and decimal minute are
used in navigation bearing and sextant
second
Degree, minute and second are used in
surveying.
See deviation, angular.
angular deviation
area
2
km
square kilometre
Topography; drainage area: watershed;
reservoir; catchment basin.
ha
hectare
Surveying and land measurement.
square metre
Surface area of tanks and small
reservoirs; small land area; crosssection of earthwork, channels, large
pipes; paving, floors, walls, roofing,
brickwork; building components such
as windows, glass insulation,
reinforcing mesh, wood products;
furnace grate, refrigerator shelf;
ship deck; load calculations.
m
2
27
Quantity
Unit Symbol Unit Name
Typical Applications
area
(continued)
cm2
square centimetre
mm2
square millimetre
Automotive radiator, brake lining,
clutch contact.
Cross-section of test specimens,
timber, wires, rods, bars, tubes,
fasteners, structural members; general
mechanical calculations.
See density, area.
kg/t
kilogram per tonne
9/t
gram per tonne
dB
decibel
area density
assay
attenuation
Mass fraction of alluvial deposits, base
metals, additives.
Mass fraction of diamonds, gems,
precious metals, additives.
Engineering and scientific calculations.
Note: The decibel is a ratio and not an
SI unit
basis weight
See grammage.
bend radius
See radius, bend.
bending moment
See moment, bending.
bond
See strength.
breadth
See dimensions, linear.
calibre
mm
millimetre
Firearms.
camber
mm
millimetre
Ship deck; road surface.
capacitance, electric
F
farad
Industrial capacitors.
UF
nF
PF
microfarad
nanofarad
picofarad
Electrical, electronic and
telecommunication circuits
and apparatus; capacitors.
pF/m
picofarad per metre
Electric cable; mutual capacitance per
unit length of transmission cable.
fF/m
femtofarad per metre
capacity, electric
current carrying
A/mm2
ampere per square millimetre
Capacitance unbalance of transmission
cable.
Electrical conductor.
capacity, heat
J/°C
joule per degree Celsius
Metal joints welding; heat sinks.
capacitance, electric
per unit length
3
capacity, heating
volumetric
MJ/(m .°C)
megajoule per cubic metre
degree Celsius
Cement
capacity, load
carrying
kg/m
kilogram per metre
Linear carrying capacity.
kg/m2
kilogram per square metre
Mg
t
megagram
tonne
kg
kilogram
kJ/(kg.°C)
kilojoule per kilogram
degree Celsius
Aircraft wing loading; rating for load
and carrying capacity of floors lifts
(for display on notices, not for
calculations).
Hoists and cranes.
Hoist conveyance load; crane; truck
or trailer payload; ship load.
Loadings generally, crane and elevator
load; truck and trailer payload; aircraft
payload or cargo capacity; aircraft fuel
capacity (gravimetric).
Cooling systems; rocks.
J/(kg.°C)
joule per kilogram degree
Celsius
Transformer oil.
m3
cubic metre
Large tanks and containers; reservoirs.
L
litre
ml
millilitre
Automobile luggage capacity;
automotive and domestic fuel tank;
freezer; refrigerator; oven; vehicle fuel
tank capacity; kitchenware.
Kitchenware; small fluid containers
such as for toilet goods,
Pharmaceuticals, beverages, etc.
capacity, mass
capacity, specific heat
capacity, volumetric
28
Quantity
Unit Symbol Unit Name
Typical Applications
charge, electric
kC
kilocoufomb
Battery capacity; electro-chemical
technology.
coulomb
Capacitor charge; ion flux calculations.
mC
MC
nC
millicoulomb
microcoulomb
nanocoulomb
Capacitor charge; partial discharge
measurements.
m
metre
Transmission cable (above ground,
joint use, etc.), Transport, tunnel
operations.
mm
millimetre
Transmission cable, transport,
structural components.
coefficient of heat
dissipation
W/(m2.°C)
watt per square metre
degree Celsius
Electronic components.
coefficient of heat
transfer
W/(m 2 .°C)
watt per square metre
degree Celsius
Pipeline; cooling systems; also known
as thermal conductance in mechanical
heat flow calculations.
W/(cm2.°C)
watt per square centimetre
degree Celsius
Cooling of tranformer windings.
reciprocal degree Celsius
Engineering and scientific calculations.
m2/kg
metre squared per kilogram
Paper.
mm*"1
reciprocal millimetre
Paper.
m2/kg
metre squared per kilogram
Paper.
mm--1
reciprocal millimetre
Paper.
reciprocal megapascal
Geotechnical calculations, soil
compressibility, compressibility of
reservoir fluid in petroleum production
operations.
mole per cubic metre
Ionic concentration in brine; chemical
analysis.
mole per litre
Acid or base concentration.
millimole per cubic metre
Ionic concentration in water.
kilogram per cubic metre
Chemical analysis; mass concentration
of gas and liquid; total dissolved solids
in liquids; concrete mix components.
Hydrogen sulphide in natural gas;
water hardness; salt in crude oil.
Pollution in air; water content of natural
gas; sulphur compounds in sweet gas.
Gas or vapour in ambient air.
Mass concentration of gas and liquid;
liquid spray mixture.
Liquid spray mixture; metal in fluid;
water treatment.
circumference
clearance
See dimensions, linear.
coefficient of linear
expansion
coefficient of
specific
light absorption
(based on basis
weight)
(based on thickness)
coefficient of specific
light scattering
(based on basis
weight)
(based on thickness)
1
compressibility
MPa-
concentration
mol/m3
mol/L
mmol/m
concentration, mass
conductance, electric
conductance, thermal
kg/m
3
3
g/m3
gram per cubic metre
mg/m3
milligram per cubic metre
Mg/m3
g/L
microgram per cubic metre
gram per litre
mg/L
milligram per litre
MS
megasiemens
Conductors.
S
Siemens
Liquids.
MS
kW/(m2.°C)
microsiemens
Insulators.
kilowatt per square metre
degree Celsius
Engineering calculations.
(See also coefficient of heat transfer.)
watt per square metre
degree Celsius
Thermal insulation (U value).
W/(m 2 .°C)
29
Typical Applications
Quantity
Unit Symbol Unit S^ame
conductivity, electric
MS/m
megasiemens per metre
Metals.
S/m
Siemens per metre
Aqueous solutions and water.
mS/m
millisiemens per metre
Well logging.
nS/m
nanosiemens per metre
Transmission cable conductors.
W/(m.°C)
watt per metre degree
Celsius
Heat exchangers; pipelines.
mW/(m.°C)
milliwatt per metre degree
Celsius
Geothermics; rock.
conductivity, thermal
See also: rate, volume flow or rate,
mass flow.
consumption
contribution, sewage
m3
kL
cubic metre
kilolitre
Water consumption,
large quantity.
L
litre
Water consumption of appliances.
L/1000 km
litre per thousand kilometres
Oil consumption of vehicles.
L/100 km
litre per hundred kilometres
Fuel consumption of vehicles.
L/MJ
litre per megajoule
Fuel consumption design studies
(volume basis).
m3/t
cubic metre per tonne
Air consumption of blast furnace per
unit mass of hot metal.
kg/m3
kilogram per cubic metre
Steam consumption of turbo-blowers
per unit volume of blown air.
kg/t
kilogram per tonne
Fuel consumption of blast furnace per
unit mass of hot metal.
kg/MJ
kilogram per megajoule
Fuel consumption design studies
(mass basis); steam consumption of
turbo-alternators, fuel consumption of
aircraft engines driving propellers
(mass basis).
g/kJ
gram per kilojoule
Oil consumption of aircraft piston
engines (mass basis).
kg/(kN.h)
kilogram per kilonewton hour
Fuel consumption of aircraft jet
engines (mass basis).
m3/d
cubic metre per day
Sewage contribution per person.
current carrying capacity
current electric
density
See capacity, electric current carrying.
MA
megaampere
Lightning.
kA
kiloampere
Large power system currents; rating of
circuit breakers; short circuits.
ampere
Currents in transmission and
distribution circuits; equipment and
apparatus rating, calibration and
testing.
mA
MA
nA
pA
milliampere
microampere
nanoampere
picoampere
Communication and
electronic circuits;
leakage current
measurements; calibration.
kg/m3
kilogram per cubic metre
Density of solids, liquids, gases.
kg/L
kilogram per litre
Paint, emulsions, oil.
3
gram per cubic centimetre
Inks for printing and graphic arts.
2
kilogram per square metre
Slabs and plates.
gram per square metre
Fabric.
kilotex per square centimetre
Carpet pile.
kg/m
kilogram per metre
Tubular goods, bars, beams, oil in
pipeline; wire rope; electric cables.
g/m
gram per metre
Electric wire.
tex
tex
Yarn.
g/cm
density, area
kg/m
2
g/m
ktex/cm
density, linear
2
30
Quantity
Unit Symbol Unit Name
Typical Applications
density, magnetic flux
T
ml
MT
nT
tesla
miilitesla
microtesla
nanotesla
Magnetic circuits.
density of heat flow
rate
kW/m2
kilowatt per square metre
Boilers.
W/m2
m
watt per square metre
metre
Walls and windows.
Mine shafts; boreholes, wells; water;
snow; buried depth of transmission
cables; pipes; also on charts.
dm
cm
decimetre
centimetre
Spacing of draft marks on ship's hull.
Dipsticks.
mm
millimetre
mrad/m
milliradian per metre
irrigation watering; rainfall; penetration
of preservatives.
Pipeline.
depth
deviation, angular
diameter
dielectric strength
diffusion coefficient
diffusivity, thermal
dimensions, linear
—breadth
—circumference
—diameter
—height
—length
—radius
—thickness
—width
mm2/s
2
Square millimetre per second
mm /s
km
square millimetre per second
kilometre
m
metre
cm
centimetre
mm
millimetre
See dimensions, linear.
See strength, dielectric.
Thermal studies.
Thermal studies.
Length of transmission lines, long pipes
and channels.
Overall dimensions of buildings,
dams, ships, tents and tarpaulins,
sporting criteria
Length of building materials generally,
beams, spans, trenches, curbs, fences,
conduit, wire, cable and rope, logs,
poles, lumber, trees, carpets, fabric,
anchor cables, conveyor belts, magnetic
tape, boats and canoes, recreational and
sporting criteria.
Width of roads, right of way, truck
loads.
Height of columns, masts and towers,
waterfalls, hydraulic head, diving
boards, survey heights, conduit bend
radius and depth of cover.
Thickness of aquifer, well drawdown
and level.
Dimensions of human body, clothing,
linen, cookware, household appliances,
shipping container, paper cut size.
Length of sporting accessories shoe
lace, slide fastener, knitting needles.
Width of carpet, cloth, paper rolls,
sporting accessories.
Diameter of paper roils, balls and bats
in sports.
Dimensions in buildings, of building
components, equipment racks and
frames, machinery, vehicles, tools,
fasteners, wood knots; also on technical
drawings.
Height of curb, carpet pile.
Width of conveyor belt, cloth (if less
than 30 cm), curb, slide fastener.
Thickness of baking utensils, conveyor
belt, cable sheath, insulation film, ice
formation on towers and masts, drilling
fluid filter cake, fabric, yarn, panel
materials, sheet metal and plate,
sapwood.
Diameter of anchor cables, cables,
wires, conductors, conduit, ropes, bars,
pipes.
Radius of drilled wells. Deflection of
beams.
Length of conduit couplings, fibres.
31
Quantity
Unit Symbol Unit Name
Typical Applications
dimensions, linear
(continued)
pm
micrometre
Thickness of coatings (paint,
galvanizing, etc.); thin sheet materials;
size of fine aggregate.
displacement
m3
cubic metre
Pumps.
L
litre
Pumps, compressors, engines.
ml
millilitre
Pumps.
W
mW
Electrical and electronic components.
MW
watt
milliwatt
microwatt
km
kilometre
Transportation (water, land, air);
transmission tower spacing; radio links;
long-distance race courses.
m
metre
Surveys; sports and games; automobile
braking; loading point intervals of
transmission cable; manhole spacing.
mm
millimetre
Electrical creepage.
nautical mile
Nautical and aeronautical navigation
and meteorology.
dissipation, power
distance
dosage, chemical
mg/L
milligram per litre
Water treatment plants.
dosage, soil, mass
kg/ha
kg/m2
kilogram per hectare
kilogram per square
metre
Agricultural chemicals.
dosage, soil, volume
L/ha
L/m2
litre per hectare
litre per square metre
Agricultural chemicals.
dose equivalent
Sv
sievert
Radioprotection
draft
See depth.
drawdown
m
metre
Wells.
drop, vertical
m
metre
Slalom and downhill sfc
courses.
dynamic balance
moment
effort, tractive
See moment, dynamic balance.
N/kg
newton per kilogram
Vehicles.
electric field gradient
See field strength, electric.
electric field strength
See field strength, electric.
elevation
m
metre
Surveys, maps and charts.
energy
GJ
gigajoule
Mechanical and thermodynamic
calculations, bulk sale of gas.
MJ
megajoule
Heating; refrigeration; air conditioning;
kinetic energy absorbed by aircraft
wheel brakes; energy of explosive
source; bulk sale of gas.
kJ
kilojoule
Biology; dietetics; energy of spark
source (geophysics); absorbed energy
in impact testing of materials.
joule
Mechanical and thermodynamic
calculations.
microjoule
Scientific and research work.
TW.h
GW.h
terawatt hour
gigawatt hour
System electrical energy production and
generation.
MW.h
megawatt hour
Electrical energy production and
consumption; thermal energy of process
steam.
kW.h
kilowatt hour
Electrical energy consumption and
billing; battery energy storage.
M J/m3
megajoule per cubic metre
Volumetric heating value of gaseous
fuel.
J/m3
joule per cubic metre
Strain energy per unit volume.
—quantity of heat
—work
energy, per unit volume
32
Quantity
Unit Symbol Unit Name
Typical Applications
energy, per unit volume
(continued)
energy, specific
MJ/L
megajoule per litre
Volumetric heating value of liquid fuel.
MJ/kg
megajoule per kilogram
Psychrometric calculations; specific
energy of fuel.
energy, surface
mJ/m2
millijoule per square metre
Chemical analysis.
enthalpy
MJ
megajoule
Engineering and scientific calculations.
kJ
kilojoule
Gas processing.
enthalpy, molar
J/mol
joule per mole
Gas processing.
enthalpy, specific
MJ/t
megajoule per tonne
Steel.
kJ/kg
kilojoule per kilogram
Petroleum pipeline.
kJ/°C
kilojoule per degree
Celsius
Refrigeration and air conditioning.
J/°C
joule per degree Celsius
Fuel.
entropy, specific
kJ/(kg.°C)
kilojoule per kilogram
degree Celsius
Refrigeration and air conditioning.
exposure, light
lx.s
lux second
Photography.
field strength, electric
MV/m
megavolt per metre
Electrical strees in gas, liquid and solid
media; dielectric value of insulating
materials.
kV/m
V/m
kilovolt per metre
volt per metre
Gradient of electric fields.
rnV/m
millivolt per metre
Broadcasting and antenna field
patterns; magnetotellurics.
pV/rn
microvolt per metre
Broadcasting and antenna field
patterns; magnetotellurics; radio noise
measurements.
A/mm
ampere per millimetre
Transformer leakage field strength.
entropy
field strength,
magnetic
See specific surface.
fineness
finish, surface
mm
millimetre
Coated abrasives.
Mm
micrometre
Machining.
See rate.
flow rate
2
flux, heat
mW/m
milliwatt per square metre
Geothermics.
flux, magnetic
mWb
milliweber
Magnetic circuits.
flux, radiant
mW
milliwatt
Antennae; continuous wave laser.
force
MN
meganewton
Rope pull force in hoists; buckling force
(load) in columns; downhole
equipment bearing load.
kN
kilonewton
Forces in columns, piles, ties,
prestressing tendons, cables; rated
dead load of drilling equipment.
daN
decanewton
Drilling mechanics, e.g. load on bit
N
newton
Automobile hand brake lever effort,
pedal effort, clutch spring force;
drag bar pull force; frictional force in
drilling fluids testing.
MN/mm
N/mm
meganewton per millimetre
newton per millimetre
Roll force per unit width in rolling mill.
kN/m
kilonewton per metre
Corrugated board ring crush; linear
force distribution.
force per unit length
Note: It is recommended that these
fractions be expressed as
dimensionless numbers, i.e. without any
associated unit.
fraction, mass
fraction, mole
fraction, volume
frequency
GHz
gigahertz
Electronics and communications.
MHz
megahertz
Electronics and communications; radio
interference; ultrasonics.
33
Quantity
Unit Symbol Unit Name
Typical Applications
frequency
(continued)
kHz
kilohertz
Electronics and communications; radio
interference; ultrasonics; acoustics;
geotechnical studies; vibration studiesl
Hz
hertz
Electric power systems; acoustics;
vibration studies.
r/min
revolution per minute
Rotating machine speeds; electrical,
hydraulic, or pneumatic tools; automatic
control instruments; bit rotation speed
of downhole equipment.
r/s
revolution per second
frequency, rotational
High speed rotating machines and tools.
gradient electric field
See field strength, electric.
gradient, elevation
Usually expressed as a ratio.
gradient pressure
gradient temperature
grammage
kPa/m
kilopascal per metre
Petroleum production operations;
reservoirs.
Pa/m
pascal per metre
Mine ventilation friction loss.
kPa/km
kilopascal per kilometre
Pipelines.
°C/km
degree Celsius per kilometre
Geothermics.
°C/m
degree Celsius per metre
Refrigeration.
2
gram per square metre
Paper and paperboard.
3
g/m
hardness, water
g/m
gram per cubic metre
See also concentration, mass.
head
m
metre
Fluid mechanics.
heat dissipation
See dissipation, power.
heat flow intensity
See intensity, heat flow.
heat flux
See flux, heat.
heat flux density
See density of heat flow rate.
head of hydration
kJ/kg
kilojoule per kilogram
Cement.
heat, latent, specific
(Also commonly
called latent heat.)
kJ/kg
kilojoule per kilogram
Steam; evaporation.
heat transfer
coefficient
See coefficient heat transfer.
height
hiding power
See dimensions, linear.
2
m /L
square metre per litre
hydrodynamic
permeability
illuminance
See permeability, hydrodynamic.
dalx
Lighting.
decalux
impact energy
impedance, acoustic
Paint and coatings.
See energy.
Pa.s/m3
pascal second per cubic metre
Ultrasonic testing and noise,
impedance, acoustic
G Pa.s/m
gigapascal second per metre
Geophysics.
specific
Note: This is acoustic impedance per unit area and therefore the use of the term specific is questionable.
impedance, electric
ohm (multiples,
Electric circuits and components,
sub-multiples)
*A range of prefixes is used, depending on magnitude.
inductance (also self
and mutual)
H
mH
MH
henry
millihenry
microhenry
Electric circuits and components.
inductance per unit
length
MH/m
microhenry per metre
Transmission cables, conductors.
inertia, rotational
kg.m2
kilogram metre squared
Dynamics of flywheel.
kilowatt per square metre
Heat calculations.
watt per square metre
Heat calculations.
(See also density of heat flow rate.)
intensity, heat flow
2
kW/m
2
W/m
34
Quantity
Unit Symbol Unit Name
Typical Applications
intensity, luminous
cd
Lighting,
candela
intensity, magnetic
intensity, sound
See density, magnetic flux.
2
W/m
watt per square metre
length
level elevation
Acoustics.
See dimensions, linear.
m
metre
Surveys, maps and charts.
linear expansion
coefficient
See coefficient, linear expansion.
load or loading
See mass, force or stress.
load carrying capacity
See capacity, load carrying, or capacity,
mass.
loss, fluid
luminance
See volume, fluid loss.
cd/m2
candela per square metre
Lighting.
magnetic field
strength
See field strength, magnetic.
magnetic flux
See flux, magnetic.
magnetic flux density
See density, magnetic flux.
magnetic permeability
See permeability, magnetic.
mass
Mg
megagram
Large masses; air cargo; rating of hoists
and cranes.
tonne
Large masses such as grain, coal, fuel,
structural steel, reinforcement, concrete,
wood, heavy equipment, ship's cargo,
truck loads, dead load on structures;
rating of lifting equipment.
kg
g
kilogram
Mass of items in general.
gram
Mass of small items such as mail,
groceries, etc.
mg
milligram
Mass of very small items such as
Pharmaceuticals.
mass concentration
See concentration, mass.
mass fraction
See fraction, mass.
mass, molar
mass per unit area
mass per unit length
milligram per mole
Gas, vapour.
kg/m
kilogram per square metre
See also density, area.
Slabs, plates and similar items of
uniform thickness; load distribution on
floors - not to be confused with force
and stress calculations.
g/m2
gram per square metre
Thin sheet materials, coatings; fabric.
kg/m
kilogram per metre
See also density, linear.
Wire rope, electric cable, beams, bars,
tubular goods and similar items of
uniform cross-section; load on
conveyor belts, beams; ice load on
conductors.
gram per metre
Cord, wire, and similar items of uniform
cross section.
mg/mol
2
modulus of elasticity
GPa
MPa
gigapascal
megapascal
Young's modulus, rigidity modulus, bulk
modulus, of materials.
modulus, section
m3
cubic metre
Midship section of ship.
mm
cubic millimetre
Properties of structural shapes and
sections (beams, columns, etc.)
modulus, tensile
kPa
kilopascal
Properties of materials.
molality
mol/kg
mole per kilogram
Anion and cation (drilling fluid).
3
molar concentration
See concentration.
molar enthalpy
See enthalpy, molar.
35
Quantity
Typical Applications
Unit Symbol Unit Name
See mass, molar.
molar mass
moment bending
MN.m
kN.m
N.m
meganewton metre
kilonewton metre
newton metre
Mechanical engineering calculations.
moment, dynamic
balance
mN.m
millinewton metre
Mechanical engineering calculations.
moment of inertia
kg.m2
kilogram metre squared
Mechanical engineering calculations.
moment, dipole
C.m
coulomb metre
Electrical engineering calculations.
ampere square metre
Electrical engineering calculations.
m
metre to the fourth power
Ship's midship section.
mm4
millimetre to the fourth
power
Properties of structural shapes and
sections (beams, columns, etc.),
pipelines.
kN.m
kilonewton metre
Mechanical engineering calculations.
N.m
newton metre
Mechanical engineering calculations.
moment static
balance
g.mm
gram millimetre
Mechanical engineering calculations.
moment torsional
kN.m
kilonewton metre
Mechanical engineering calculations.
momentum
kg.m/s
kilogram metre per second
Mechanical engineering calculations;
fluid flow in sedimentology.
momentum, angular
kg.m2/s
kilogram metre squared
per second
Mechanical engineering calculations.
moment magnetic
moment of inertia,
area
(Also known as
second moment of
area.)
moment overturning
2
A.m
4
mutual capacitance
See capacitance, electric.
offsets
mm
millimetre
Drilling, downhole equipment.
overtravel
mm
millimetre
Pumps, drilling mechanics.
overturning moment
See moment overturning.
permeability,
hydrodynamic
ng/(Pa.s.m)
nanogram per pascal
second metre
Water vapour transmission.
permeability,
magnetic
H/m
mH/rn
henry per metre
millihenry per metre
Magnetic circuits.
permeance
ng/(Pa.s.m2)
nanogram per pascal
second squared metre
Water vapour transmission through
walls.
permittivity
pF/m
picofarad per metre
Electric circuits, capacitors.
pitch
mm
millimetre
Screw threads; pumps.
pollution
potential, electric
potential, magnetic
vector
See concentration, mass.
MV
megavolt
Very high voltage testing and lightening
studies.
kV
kilovolt
Generation, transmission, distribution.
V
volt
Secondary distribution; appliances;
batteries; calibration; low voltage
circuits; potential or emulsion stability
of drilling fluids.
mV
millivolt
Low voltages for electronics,
thermocouples, calibration; corrosion
potential; spontaneous electric potential
in well logging and perforating.
microvolt
Very low voltages for electronics,
telecommunication, noise
measurements; geophysics.
kA
A
kiloampere
ampere
Calculation of transformer and reactor
characteristics.
Wb/m
weber per metre
Magnetic circuits.
36