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IS 10005 (1994): SI Units and Recommendations for the Useof
their Multiples and of Certain Other Units [MSD 10:Social
Responsibility]
-
IS looo5: 1994 -I!50 looo: 1992
Indian Sta~ndard SI UNITS AND RECOMMENDATIONS FOR THE USE OF
THEIR MULTIPLES AND OF CERTAIN
OTHER UNITS (Second Revision)
UDC 006.057.5
Q BIS 1994
BU-REAU OF IN~DIAN STA~NDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR
MARG
NEW DELHI 110002
November 1994 Price Group 9
-
Basic Standards Sectional Committee, MSD 1
NATIONAL FOREWORD
This Indian Standard (Second Revision) which is identical with
IS0 1000 : 1992 SI units and recommendations for the use of their
multiples and of certain other units, issued by the International
Organization for Standardization (ISO), was adopted by the Bureau
of Indian Standards on the recommendation of the Basic Standards
Sectional Committee (MSD 1) and approval of the Management and
Systems Division Council.
The text of the IS0 Standard has been approved as suitable for
publication as Indian Standard without deviations. Certain
conventions are, however, not identical to those used in Indian
Standards. Attention is particularly drawn to the-following:
a) Comma ( , ) has been used as a decimal marker while in Indian
Standards the current practice is to use full point ( ) as the
decimal marker.
b) Wherever the words International Standard appear referring to
this standard, they should be read as Indian Standard.
This standard was first published in 1980 and then revised in
1985.
In this second revision, the following changes have been
made:
a) Quantities and units from IS 1890 (Parts 9, 10, 12, and
13)/ISO 31 (Parts 9, 10, 12 and 13) have been added to Annex A
(Normative) giving examples of decimal multiples and sub- multiples
of SI units and of some other units which may be used. A cross
reference to the item numbers of relevant standard has been
made.
b) The old definition of metre in Annex B has been replaced by
new definition.
c) The decision by International Committee for Weights and
Measures (CIPM) in 1980 concerning the status of supplementary
units has been incorporated.
In the adopted standard, normative references appear to certain
International Standards for which Indian Standards also exist. The
corresponding Indian Standards which are to be substituted in their
place are listed below along with their degree of equivalence for
the editions indicated:
In terna tional Standard
IEC 27-l : 1971
IS0 31-l : 1992
IS0 31-2 : 1992
IS0 31-3 : 1992
IS0 31-4 : 1992
IS0 31-5 : 1992
Corresponding Indian Standard
IS 3722 (Part 1) : 1983 Letter symbols and signs used in
electric technology : Part 1 General guidance on symbols and
subscripts (first revision)
IS 1890 (Part 1) : 1994 Quantities and units: Part 1 Space and
time (first revision)
IS 1890 (Part 2) : 1994 Quantitiesand units: Part 2 Periodic and
related phenomena (second revision)
IS 1890 (Part 3) : 1994 Quantities and units: Part 3 Mechanics
(second revision)
IS 1890 (Part 4) : 1982) Quantities, units and symbols: Part 4
Heat (first revision)
IS 1890 (Part 5) : 1994 Quantities and units: Part 5 Electricity
and magnetism (first revision)
Degree of Equivalence
Technically equivalent
Identical
Identical
Identical
Technically equivalent
Identical
I) Under Revision
(Continued on third cover)
-
IS 10005: 1994 IS0 1000:1992
Indian Standard SI UNITS AND RECOMMENDATI.ONS FOR~THE USE OF
THEIR IViJLTlPLES AND OF CERTAIN
OTHER UNITS (Second Revision)
1 Scope
This International Standard
a)
b)
describes the International System of Units) (in clauses 3, 4
and 6);
recommends selected decimal multiples and sub- multiples of St
units for general use and gives certain other units which may be
used with the International System of Units (in clauses 5 and 7,
and annex A);
quotes the definitions of the SI base units (in an- nex B).
Normative reference
The following standard contains provisions which, through
reference in this text, constitute provisions of this International
Standard. At the time of publica- tion, the edition indicated was
valid. All standards are subject to revision, and parties to
agreements based on this International Standard are encouraged to
in- vestigate the possibility of applying the most recent edition
of the standard indicated below. Members of
IEC and IS0 maintain registers of currently valid International
Standards.
IEC 27-l :1971,2) Letter symbols to be used in elec- trical
technology - Part 1: General
3 SI units
The name International System of Units (Systeme International
dunites), with the international abbrevi- ation SI, was adopted by
the 11 th General Conference on Weights and Measures (Conference
G&kale des Poids et Mesures, CGPM) in 1960.
This system includes:
- base units
- derived units including supplementary units
which together form the coherent system of SI units.
3.1 Base wits
The International System of Units is based on the seven base
units listed in table 1.
1) Full InformatIon about the lnrernational System of Units IS
given in a publication by the InternatIonal Bureau of Weights ana
Measures (Bureau lnternationai des Poids et Mesures, BIPM): Le
Sysr&ne lnremarional dlJnir6s (SO, irkluding an authorized
English transiation.
2) 5th edition. currently being revised.
1
-
IS looo5: 1994 IS0 MOO : 1992
Table 1 - SI base units
SI base unit Base quantity
Name Symbol
length metre m
mass kilogram kg
time second S
electric current ampere A
thermodynamic kelvin K temperature
amount of substance mole mol
luminous intensity candela cd
For the definitions of the base units, see annex 6.
~3.2 Derived units including supplementary units
Derived units are expressed algebraically in terms of base
units. Their symbols are obtained by means of the mathematical
signs of multiplication and division; for example, the SI unit for
velocity is metre per sec- ond (m/s).
For some of the SI derived units, special names and symbols
exist; those approved by the CGPM are listed in tables 2 and 3.
The SI units radian and steradian are called supple- mentary
units. They are dimensionless derived units (more precisely,
derived units of dimension one) with special names and symbols.
Although the co- herent unit for plane angle and for solid angle is
ex- pressed by the number 1, it is convenient to use the special
names radian (rad) and steradian (sr) respec-
tively instead of the number 1 in many practical cases; for
example the SI unit for angutar velocity can be written as radian
per second (rad/s).
It may sometimes be useful to express derived units in terms of
other derived units having special names; for example, the SI unit
for electric dipole moment is usually expressed as C - m instead of
A. s - m.
4 Multiples of SI units
The prefixes given in table4 are used to form names and symbols
of multiples (decimal multiples and sub- multiples) of the SI
units.
The symbol of a prefix is considered to be combined with the
kernel symbol to which it is directly at- tached, forming with it a
new symbol (for a decimal multiple or sub-multiple) which can be
raised to a positive or negative power, and which can be com- bined
with other unit symbols to form symbols for compound units.
EXAMPLES
= (JO-* m)3 = 10b6m3
1 ps- z (lo-6s)- = 106s-
1 mm*/s = (10m3 m)*/s = lo- m*/s
Compound prefixes shall not be used; for example, write nm for
nanometre, not mFm.
NOTE 1 For historical reasons the name of the base unit for
mass, the kilogram, contains the name of the SI prefix kilo. Names
of the decimal multiples and sub-multiples Df the unit of mass are
formed by adding the prefixes to the word gram, e.g. milligram (mg)
instead of microkilogram
Mg).
3) In this case, the term kernel symbol means only a symbol for
a base unit or a derived unit with a special name. See, however,
note 1 in clause 4 about the base unit the kilogram.
2
-
IS 10005 : 1994 IS0 1000: 1992
Table 2 - SI derived units with special names, including SI
supplementary units
SI derived unit Derived quantity
Spatial name Symbol Expressed in terms of SI base units and St
derived units
plane angle
solid angle
frequency
force
pressure, stress
radian rad
steradian sr
hertz Hz
newton N
Pascal Pa
1 rad = 1 m/m = 1
1 sr=l m2/m2=1
1 Hz = 1 s-l
1 N = 1 kg - m/s2
1 Pa = 1 N/m2
energy. joule J 1 J=l N-m work, quantity of heat
power, watt W 1 W = 1 J/s radiant flux
electric charge, coulomb C 1 C=l A-s quantity of electricity
eiectric potential, volt V 1 V=l W/A potential difference,
tension, electromotive force
capacitance farad F 1 F=l C/V
electric resistance ohm a 1 Q = 1 V/A
electric conductance siemens S 1 s = 1 a-
magnetic flux weber Wb 1 Wb=l V.s
magnetic flux density tesla T 1 T=l Wb/m2
inductance henry H 1 H = 1 Wb/A
Celsius temperature degree Celsiusl) C 1 CF~ K
luminous flux lumen Im 1 Im = 1 cd a sr
illuminance lux IX 1 lx = 1 lm/m2
1) Degree Celsius is a special name for the unit kelvin for use
in stating values of Celsius temperature. (See also note6
concerning the kelvin in annex B.)
3
-
IS 19905 : 1994 IS0 1000: 1992
Table 3 - SI derived units with special names admitted for
reasons of safeguarding human health I
.Derived quantity
SI derived unit
Special name Symbol Expressed in tarms of SI base units
and SI derived units
activity (of a radionuclide)
absorbed dose, specific energy imparted, kerma, absorbed dose
index
becquerel
gray
Bq
GY
1 Bq = 1 s-
1 Gy = 1 J/kg
dose equivalent, dose equivalent index
sievert sv 1 Sv = 1 J/kg
Table 4 - Sl prefixes
PWfiX Factor
Name Symbol
yotta Y zetta 2
1018 exa E 1o15 peta P
lOI2 tera T
log giga G lo6 mega M
lo3 kilo k
lo2 hecto h 10 deca da 10-l deci d lo-* centi. C
1o-3 milli m 1o-6 micro
Or:*
CI nano n
10 pica P
lo-l5 femto f 1 o-l8 atto a lo-* zepto 2 1o-24 yocto Y
5 Use of SI units and their multiples
5.1 The choice of the appropriate multiple (decimal multiple or
sub-multiple) of an SI unit is governed by convenience, the
multiple chosen for a particular- ap- plication being the one which
will lead to numerical values within a practical range.
5.2 The multiple can usually be chosen so that the numerical
values will be between 0,l and 1 000. In the case of a compound
unit containing a unit to the second or third power, this is not
always possible.
EXAMPLES
I,2 x lo4 N can be written as 12 kN
0,003 94 m can be written as 3,94 mm
1 401 Pa can be written as 1,401 kPa
3,l x 10-8s can be written as 31 ns
However, in a table of values of the same quantity or in a
discussion of such values within a given context, it will generally
be better to use the same multiple for all items, even if some of
the numerical values will then be outside the range 0,l to 1 000.
For certain quantities in particular applications, the same
multiple is customarily used; for example, the millimetre is used
for dimensions in most mechanical engineering drawings.
5.3 The number ~of prefixes used in formrng com- pound units
should be limited as far as is compatible with practical usage.
5.4 Errors in calculations can be avoided more easrly if all
quantities are expressed in SI units, powers of 10 being used
instead of prefixes.
6 Rules for writing unit symbols
6.1 Unit symbols shall be printed in roman (upright) type
(irrespective of the type used in the rest of the text), shall
remain unaltered in the plural, shail be written without a final
full stop (period) except for normal punctuation, e.g. at the end
of a sentence, and shall be placed after the complete numerical
value in
4
-
IS 10005 : 1994 IS0 1uw: 1992
the expression for a quantity, leaving a space be- 7 tween the
numerical value and the unit symbol,
Non-S1 units which may be used with SI units and their
multiples
Unit symbols shall in general be written in lower case letters
except that the first letter is written in upper case when the name
.of the unit is derived from a proper name.
7.1 There are certain units, outside the SI, recog- nized by the
CIPM as having to be retained because of their practical importance
(see tables 5 and 6).
EXAMPLES
m metre
S second
A ampere
Wb weber
7.2 Prefixes given in table4 may be attached to some of the
units given in tables 5 and 6; for example, millilitre, ml. (See
also annex A, column 6.)
7.3 In a limited number of cases, compound units are formed with
the units given in tables 5 and 6 to- gether with SI units and
their multiples; for example, kg/h; km/h. (See also annex A,
columns 5 and 6.)
6.2 When a compound unit is formed by multipli- cation of two or
more units, this should be indicated in one of the following
ways:
N-m, Nm
NOT5 ,
2 In systems with limited character sets a dot on the line is
used instead of a half-high dot.
3 The latter form may also be written without a space, provided
that special care is taken when the symbol for one of the units is
the same as the symbol for a prefix, e.g. mN is used only for
millinewton, not for metre newton.
When a compound unit is formed by dividing one unit by another,
this should be indicated in one of the fol- lowing ways:
m S m/s, m - s-l.
A solidus (/) shall not be followed by a multiplication sign or
a division sign on the same line unless parentheses are inserted to
avoid any ambiguity. In complicated cases negative powers or
parentheses shall be used.
NOTE 4 There are some other units outside the SI which are
recognized by the CIPM for temporary use. They are given in column
7 of the table in annex A and marked by an asterisk (*).
Table 5 - Units used with the SI
Unit Quantity
Name Symbol Definition
:ime minute min 1 min = 60 s
hour h 1 h = 60 min
day d 1 d=24h
olane angle degree I0 = (x/l 80) rad
minute I = (l/60)
second 1 = (l/60)
volume litre I, L) 1 I=1 dm3
mass tonnes) t 1 t=103kg
1) The two symbols for the litre are on an equal footing. The
CIPM will, however, make a survey on the development of the use of
the two symbols in order to see if one of the two may be sup-
pressed.
2) Also called the metric ton in the English lan- guage.
-
5
-
IS 10005: 1994 IS0 1000 : 1992
Table 6 - Units used with the SI, whose values in SI units are
obtained experimentally
Quantity
energy
mass
Name
electronvolt
unified atomic mass unit
Unit
Symbol Definition
eV The electronvolt is the kinetic energy acquired by an
electron in passing through a potential difference of 1 volt in
vacuum: 1 eV 2: 1,602 177 x lo-J.
U The unified atomic mass unit is equal to l/12 of the mass of
an atom of the nuclide *C:
I 1 u z 1,660 540 x lo-* kg.
6
-
IS 10005: 1994 IS0 1000 : 1992
Annex A
Examples of -decimal multiples and sub-multiples of SI units and
of some
(normative)
other units which may be used
For a number of commonly used quantities, examples of decimal
multiples and sub-multiples of SI units, as well as of some other
units which may be used, are given in this annex. It is suggested
that the selection shown, while not intended to be restrictive,
will none the less prove helpful in presenting values of quantities
in an identical manner in similar contexts within the various
sectors of technology. For some needs (for example, in applications
in science and education), it is recognized that greater freedom
will be required in the choice of decimal multiples and
sub-multiples of SI units than is exemplified in the list which
follows.
Item No. In IS0 31:
1992
Units outsido the SI recognized Selection by the ClPM as having
to be
of retained, and for spocisl cases multiples some of their
combina-tlons with
Quantity SI unit and sub- SI units Remarks and information
about
multiples of the SI
Multiples or units used in special fields
unit Units sub-multiples of
units -given in column 5
1 2 3 4 5 5 7
Part 1: Space and time
- 1-l angle, b rad (plane angle) (radian)
gon [gon (;r grade)], 1 gon=---
200 rad
0 If the radian is not used, the cnits (degree) degree or gon
(or grade) may be 1 -cad used. Decimal subdivisions of
180 mrad
degrea are preferable to minute , and second for most
applications.
(minute) For the units degree, minute and
lL-& second for plane angle, there shall be no space between
the
I, numerical value and the unit
(secon:~ symbol.
1 e- 60
prad
1-2 solid angle Eteradian)
l-3.1 length km 1 nautical mile* = 1 852 m
Retre) (exactly)
cm mm
* pm
Recognized by the CIPM for
nm temporary use.
K
7
-
IS loo05 : 1994 IS0 1000: 1992
Units outside the SI recognized
Selection by the CIPM es having to be
of retained, and for special cases
ltom No. multiples some of their combinations with
in IS0 31: Quantity SI unit end eub- SI units Remarks and
information about
1992 multlples Multlples or units used in special fields
ofthrSI unit Units
sub-multiples of units given in
column 5 -
1 2 3 4 6 6 7
I-4 area km2 m2
ha* (hectare), 1 ha = lo4 m2
dm2 a* (are), 1 a = lo2 m2
cm2 mm2
l Recognized by the CIPM for temporary use.
t-5 volume m3 In 1964, the CGPM declared that hi 1 hl = IO-
m3
the name litre (I) may be used as
dm3 a special name for the cubic
I, L decimetre (dm3) and advised (litre) against the use of the
name litre 1 I= 10V3m3=
for high-precision measure- ments.
1 dm3 cl 1 cl E 10T5 m3
See also footnote 1) to table 5.
cm3 ml 1 ml = 10m6 m3 = 1 cm3
mm3
l-7 time
Gecond)
ks
ms c1s ns
d (day) 1 d=24h (exactly) h (hour) 1 h = 60 min (exactly)
min (minute) 1 min = 60 s (exactly)
Other units such as week, month and year (a) are in common use.
The definitions of month and year often need to be specified.
l-8 angular velocity
rad/s
I-10 velocity m/s km/h 1 km/h =
l-11.1 accteleration m/s2
mm/h & m/s
1 knot* = 1,852 km/h (exactly) = 0,514 444 m/s
For the hour, see item No. 1-7.
l Recognized by the CIPM for temporary use.
8
-
IS 10905: 1994 IS0 1000: 1992
Item No. in IS0 31:
1992 Quantity SI unit
Units outside the SI recognized
Selection by the CIPM as having to be
of retained, and for special cases
multiples some of their combinations with
and sub- SI units Remarks and information about
multiples Multiples or units used-in special fields
of the SI unit Units
sub-multiples of units given in
column 5
1 2 3 4
Part 2: Periodic and related phenomena
2-3.1 frequency THz GHz MHz kHz
HZ (hertz)
2-3.2 rotational S -1
frequency
2-4 angular rad/s frequency
5
min-
6 7
The designations revolutions per minute (r/min) and revo-
lutions per second (r/s) are widely used for rotational fre- quency
in specifications on rotat- ing machinery. (See also IEC 27-l .)
For the minute, see item l-7.
Part 3: Mechanics
3-1
3-2
3-5
3-7
mass Mg t See footnote 2) to table 5. (tonne) 1 t=103kg
kg (kilogram)
g mg Pg
volumic Mg/m3 or kg/dm3
t/m3 or kg/l g/ml For the litre, see item No. l-6. mass,
density,
kg/m3
or g/cm3 For the tonne, see item No. 3-1.
mass density g/f
lineic mass, kg/m 1 tex = IO- kg/m = 1 g/km linear density
mglm
The unit tex is used for textile filaments.
moment of kg-m inertia
3-8
38.1
momentum
force
- kg - m/s
MN kN
N (newton)
mN
PN
9
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IS iow5 : 1994
Is0 1000: 1992
Units outside the Si recognized
Selection by the CIPM as heving to be
of retained, and for special cases
Item No. multiples some of their combinations with
in IS0 31: Quantity SI unit and sub- SI units Remarks and
information about
1992 multiples Multiples or units used in special fields
of the SI unit Units
sub-multiples of unlts given in
column 5
-1 2 3 4 5 6 7
3-l 1 moment of kg - m*/s momentum,
angular momentum
3-12.1
3-15.1
3-15.2
moment of MN.m force kN . m
N.m mN-m PN B m
pressure GPa bar* (bar), 1 bar = 100 kPa MPa (exactly) kPa hPa 1
mbar = 1 hPa
Pa (Pascal)
The use of the bar shall be re-
mPa stricted to existing uses in the
PPa field of fluid pressure.
l Recognized by the CIPM for temporary use.
normal stress GPa MPa kPa
Pa
3-23 viscosity, (dynamic
viscosity)
Pa . s mPa.s
P (poise) 1 cP= 1 mPa.s
The poise and stokes are special names for CGS units. They and
their multiples and sub-multiples shall not be used together with
SI units.
3-24 kinematic viscosity
m2/s mm*/s
St (stokes) 1 cSt = 1 mm*/s
See remark on item 3-23.
3-25 surface N/m tension mN/m
3-26.1 and 3-26.2
energy. work
EJ PJ TJ GJ MJ kJ
J (joule)
mJ
lb
-
IS looo!5: 1994 IS0 1990 : 1992
ltom No. n IS0 21: Quantity
1992
1 2
l-27 power
art 4~ Heat
Units outsido the SI recognized hction by the CIPM as having to
be
of rotalnod, and for special cases multiples some of their
combinations with
Si unit and sub- SI units Romrrks and information about
multiples Multiploa or
units uwd in specirl fields OfthoSl
unit Unit8 rub-multiplesof units *on in
column 6 3 4 S 6 7
GW MW kW
W (watt)
mW PW
l-1 thermo- K dynamic (kelvin) temperature
I-2 Celsius C temperature (degree
Celsius)
The Celsius temperature-r is equal to the difference (T - TO)
between two thermodynamic
I temperatures T and To, where To =-273.15 K (exactly).
I l-3.1 linear
expansion coefficient
K-l
For the definition and the use of the degree Celsius (C), see
note6 under the definition of the kelvin in annex B.
For the degree Celsius, see item 4-2.
66
67
heat EJ PJ TJ GJ MJ kJ
J mJ
heat flow rate kW W
4-9
618.1
4-11
Cl6
thermal W/(m 8 Kl For the degree Celsius, see item conductivity
4-2.
coefficient W/(m2 - K) For the degree Celsius, see item of heat
4-2. transfer
thermal m2. K/W For the degree Celsius, see item insulance
4-2.
heat capacity kJ/K For the degree Celsius, see item J/K 4-2.
11
-
IS 10005 : 1994 IS0 1000: 1992
item No. n IS0 31:
1992 Ouantity Si unit
Units outside the Si recognized
Selection by the CiPM as having to be
of retained, and for special cases
multiples some of their combinations with
and sub- St units Remarks and information about
multiples Muitipies or units used in special fields
of the Si unit Units
rub-multiples of units given in
column 5
1 2 3 4 5 6 7
I-16.1 massic heat kJ/(kg - K) For the degree Celsius, see item
capacity J/M - K) 4-2.
I-16
619
entropy
massic entropy
J/K
J/M - K)
kJ/K
kJ/(kg . K)
For the degree Celsius, see item 4-2.
For the degree Celsius, see item 4-2.
1-21.2 massic thermo- dynamic energy
J/kg
art 5: Electricity and magnetism
i-l electric current
kA A (ampere)
mA PA nA PA
5-2
5-3 k
6-4
electric charge,
quantity of electricity
volumic charge,
volume density of charge,
charge density
areic charge, surface density of charge
A-h For the hour, see item No. l-7. 1 A-h- 3,6 kC
kC C (coulomb)
ClC nC PC
C/mm3 or GC/m3
MC/m3 or C/cm3
kc/m3 C/m3
mC/m3 PC/m3
MC/m or C/mm
C/cm2
C/m2 kc/m2
mC/m2 PC/m
12
-
IS 10005:1994 IS0 1000:1992
Units outside the SI recognized
Selection by the CIPM as having to be
of retained, and for special cases
item No. multiples some of their combinations with
in IS0 31: Quantity SI unit and sub- SI units Remerks and
information ebout
1992 multiples of the SI
Multiples or units-used in special fields
unit Units sub-multiples of
units given in column 5
1 2 3 4 5 6 7
5-5 electric field MV/m strength kV/m or
V/mm V/cm
V/m mV/m Hm
5-6.1 electric MV potential kV
V 5-6.2 potential (volt)
difference, mV tension IJJ
5-6.3 electromotive force
5-7
5-8
5-9
5-10.1
5-13
5-14
electric flux density
C/m*
electric flux
C
capacitance F (farad)
permittivity F/m
electric polarization
C/m2
electric dipole C - m moment
C/cm* kc/m*
mC/m* G/m*
MC kC
mC
mF PF nF PF
pF/m nF/m pF/m
C/cm* kc/m*
mC/m* G/m*
.
.
i
-
IS 10005:1994 IS0 1000:1992
Item No. in IS0 31:
1992 Quentity
Units outsidr the SI recognized
Selection by the CIPM as heving to be
of retained, and for special cases
multiples some of their combinations with
SI unit andsub- SI units Remarks and~lnformetion about
multiples Multiples or units used in special fields
ofthesl unit Units
sub-multiples of units given in
column 5
1
5-15
2 3 4 5 6 7
areic electric MA/m2 or current, A/mm2
electric A/cm2 current
A/m2 kA/m2
density
5-16 lineic electric kA/m or current, A/mm
linear electric A/cm current A/m density
5-17 magnetic field strength
A/m
kA/m or A/mm
A/cm
5-18.1 magnetic potential difference
A kA
mA
5-19 magnetic flux T density, (tesla)
magnetic induction
mT PT nT
5-20 magnetic flux Wb (weber)
mWb
5-21
522.1
5-22.2
5-24
5-27
magnetic vector potential
self- inductance
mutual inductance
permeability
magnetic moment,
electro- magnetic moment
Wb/m
H (henn/)
H/m
A-m
kWb/m
gblmm
mH VH nH PH
PHjm nH/m
14
-
IS 10005: 1994 IS0 1000 : 1992
Units outside the SI recognized
Selection by the ClPM as having to be
of retainad, and for special cases
Item No. multiples some of their combinations with
n IS0 31: Quantity SI unit and sub- SI units Remarks and
information about
1992 multiples Multiples or units used in special fields
of the SI unit Units
sub-multiples of unlts given in
column 5
1 2 3 4 5 5 7
i-20 magnetization kA/m or A/mm
A/m
i-29 magnetic T polarization mT
IEC magnetic N - m*/A !7-1:1971, dipole tern 88) moment
&b-m
i-33 resistance (to GCI direct MCI current) kn
Ehm) mTL w
i-34 conductance kS (of direct S current) (siemens)
mS PS
j-38 resistivity Gf2.m n-mm* Mn.m
ii-_.(= lo-n.m =pn.rr
kf2.m is also used. a-m
R-cm ma-m paam Warn
5-37 conductivity MS/m kS/m
S/m
5-38 reluctance H--l
5-39 permeance H
5-44.1 impedance, MQ (complex kn
impedance) SL mn
5-44.2 modulus of impedance,
(impedance)
544.3
5-44.4
resistance
reactance
15
-
IS 10005:1994 IS0 -1000:1992
Item No. n IS0 31:
1992 Quantity SI unit
Units outside the SI recognized
Selaction by the CIPM as having to ba
of ratainrd, and for spatial cases
multiples some of their combinations with
and sub- SI units Remarks and information about
multiplas Multiples or units used in special fields
of-the SI unit Units
sub-multiples of units given in
column 5
1 2 3 4 5 5 7
-45.1 admittance, kS (complex S
admittance) mS
ClS i-45.2 modulus of
admittance, (admittance)
i-45.3
i-45.4
i-49
conductance
susceptance
active power TW In electric power technology, ac- GW tive power
is expressed in watts MW (W), apparent power in volt am- kW Peres
(V - A) and reactive power
W in vars (var). mW
CIW nW
i-52 active energy TW.h For the hour, see item l-7. GW-h
TJ MW-h
GJ kW.h
MJ W-h 1 W.h= 3,6 kJ (exactly)
kJ J
#art 6: Light and related electromagnetic radiations
i-3 wavelength m
pm nm
pm
6-7 radiant J energy
A* (angstrom), I A = IO-~ m = IO- nm = 10e4 pm
l Recognized by the CIPM for temporary use.
6-10 radiant W power,
radiant , energy flux
6-13 radiant intensity
W/sr
16
-
IS 10005:1994 IS0 1000:1992
Units outside the Si recognized
Selection by the CiPM es heving to be
of retained, and for special cases
item No. multiples some of their combinatfons with
n IS0 31: Quantity Si unit and sub- SI units Remarks and
information about
1992 multiples of the SI
Multiples or units used in special fields
unit Units sub-multiples of
units given in column 5
1 2 3 4 5 6 7
b14 radiance W/(sr - m*)
i-15 radiant W/m* exitance
i-16
i-29
i-30
S-31
6-32
6-33
irradiance W/m*
luminous cd intensity (candela)
luminous flux Im (lumen)
quantity of light
Im - s
luminance cd/m*
luminous lm/m* exitance
Im - h 1 Im-h= 3 600 Im . s (exactly)
For the hour, see item 1-7.
6-34
6-35
illuminance
light exposure
lx
(lux)
lx * s
636.1 luminous efficacy
lm/W
Part 7: Acoustics
7-l period, s periodic time ms
Ps
7-2 frequency MHz kHz
HZ
7-5 wavelength m mm
7-6 volumic kg/m3 mass,
mass density, density
-
IS 10005 : 1994 IS0 1000 : 1992
Units outside the Slrecognizrd
Selection by the CIPM as having to~be
of retained, end for special cases
Hem No. multiples some of their combinations with
n IS0 31: Quantity SI unit end rub- SI units Remarks and
Information about
1992 multiples of the SI
Multiples or units used In special fields
unit Units sub-multiples of
units given in column 5
1 2 -3 4 5 6 7
-9.1 static Pa pressure mPa
PPa r-9.2 (instantaneous)
sound pressure
r-11 (i;;;;Tneous) m/s
particle velocity
mm/s
r-13 (instantaneous) m3/.s volume flow rate
r-14.1 velocity of sound
mls
1-16
r-17
7-18
sound power kW W
mW
FW PW
sound W/m* intensity mW/m*
pW/m* pW/m*
acoustic Pa m s/m3 impedance
.
mechanical impedance
surface _ density of mechanical impedance
N - s/m
Pa - s/m
dB.(decibel), 1 dB = 10-l B
-
IS 10005 : 1994 IS0 1000 : 1992
Units outside the SI recognized
Selection by the CIPM as having to be
of retained, and for special cases
item No. multiples some of their combinations with
in IS0 31: Quantity SI unit and sub- SI units Remarks and
information about
1992 multiples Multiples or units used in special fields
of the SI unit Units
sub-multiples of units given in
column 5
1 2 3 4 5 Q 7
7-28 sound B reduction dB index
7-29 equivalent absorption area of a surface or object
m2
7-30 reverberation s time
Pati 8: Physical chemistry and molecular physics
8-7 molar thermo- dynamic energy
J/mol kJ/mol
8-8
8-9
813
molar heat J/(mol - K) For the degree Celsius, see item capacity
4-2.
molar entropy J/(mol - K) For the degree Celsius, see item
4-2.
concentration mol/dm3 mol/l For the litre, see item l-8. of 8,
or
amount-of- kmol/m3 substance mol/m3 concentration of B
8-18
8-39
molality of solute B
diffusion coefficient
mol/kg
m*/s
mmol/kg
19
-
IS 10005 : 1994 IS0 1000 : 1992
tern No. 1 IS0 31:
1992 Quantity SI unit
Units outside the SI recognized
Selection by the CPM as having to be
of retained, and for special cases
multiples some of their combinations with
and sub- SI units Remarks and information about
multiples Multiples or units used in special fields
of the SI unit Unlts
sub-multiples of units given in
column 5
1 2 3 4 5 0 7
-41 thermal m2/s diffusion coefficient
art 9: Atomic and nuclear physics
I-28.2 mass defect kg
tnified atomic mass unit),
1 uz 1,660 540 x IO- kg
1-33 activity
Bq
MBq kBq
Ci+ (curie), 1 Ci = 3.7 x IO Bq (exactly)
l Recognized by the CIPM for temporary use.
b-34 massic activity,
specific activity
Bqlkg
MBq/kg kBq/kg
j-37 half-life
S
ms
d h
a (year) For the hour and the day, see item 1-7.
art 10: Nuclear reactions and ionizing radiations
so-1 reaction energy
J GeV WleV keV
eV (electronvolt), 1 eVk: 1,602 177 x lo-J
10-51.2
lo-52
absorbed dose
dose equivalent
GY
sv
mGy
mSv
rad* (rad), 1 rad = lo- Gy
* Recognized by the CIPM for temporary use.
rem* (rem), 1 rem = lo- Sv
l Recognized by the CIPM for temporary use.
20
-
IS 10009: 1994 IS0 1000 : 1992,
ltem No. in IS0 31:
1992 Quantity SI unit
Units outside the SI recognized
Selection by the CIPM as having to be
of retained, and for special cases
multiples some of their combinations wlth
and sub- SI unlta Remarks and information about
multiples Multiples or units used in special fields
of the SI unit Units
sub-multiples of unlts.given In
column 5
1 2 3
IO-58 exposure C/kg
Part 12: Characteristic numbers
12-1 Reynolds I number
12-8 Mach number 1 /
Part 13: Solid state physics
13-17 density of states J-/m3
13-20 Hall m3iC coefficient
4 5 6 7
R (rontgen),
mC/kg 1 R = 2,58 x 1 0p4 C/kg (exactly)
* Recognized by the CIPM for temporary use.
As prefixes cannot be used, powers of 10 may be used, e.g. Re=
1,32 x lo3
eVi/m3 For the electronvolt, see item 1 O-l.
-
13-21 thermo- V electromotive mV force
13-24
13-28.2
13-38.1
Thomson V/K coefficient
gap energy J
Curie K temperature
mV/K
fJ aJ
eV
For the degree Celsius, see item 4-2.
For the electronvolt, see item 1 O-l.
For the degree Celsius; see item 4-2.
I
21
-
IS lwo!5: 1994 IS0 1000.: 1992
Annex B (informative)
Definitions of the base units of the international system of
units
metre: The metre is the length of the path travelled by light in
vacuum during a time interval of l/299 792 458 of a second.
[17th CGPM (1983), Resolution I]
kilogram: The kilogram is the unit of mass; it is equal to the
mass of the international prototype of the kilogram.
[3rd CGPM (1901)]
second: The second is the duration of 9 192 631 770 periods-of
the radiation corresponding to the transition be- tween the two
hyperfine levels of the ground state of the caesium-133 atom.
[13th CGPM (1967), Resolution l]
ampere: The ampere is that constant current which, if maintained
in two straight parallel conductors of infinite length, of
negligible circular cross-section, and placed 1 metre apart in
vacuum, would produce between these conductors a force equal to 2 x
Leo_ newton per metre of length.
[CIPM (1946), Resolution 2 approved by the 9th CGPM (1948)]
kelvin: The kelvin, unit of thermodynamic temperature, is the
fraction l/273,16 of the thermodynamic temperature of the triple
point of water.
[13th CGPM (1967), Resolution 4)
NOTES
5 The 13th CGPM (1967, Resolution 3) also decided that the unit
kelvin and its symbol K should be used to express an interval or a
difference of temperature.
6 In addition to the thermodynamic temperature (symbol T),
expressed in kelvins, use is also made of Celsius temperature
(symbol r) defined by the equation t-T-To, where TO = 273,15 K by
definition. To express Celsius temperature, the unit degree
Celsius, which is equal to the unit kelvin, is used; in this case,
degree Celsius is a special name used in place of kelvin. An
interval or difference of Celsius temperature can, however, be
expressed in kelvins as well was in degrees Celsius.
mole: The mole is the amount of substance of a system which
contains as many elementary entities as there are atoms in 0,012
kilograms of carbon-l 2. When the mole is used, the elementary
entities must be specified -and may be atoms, molecules, ions,
electrons, other particles, or specified groups of such
particles.
[14th CGPM (1971), Resolution 33
candela: The candela is the luminous intensity, in a given
direction, of a source that emits monochromatic radiation of
frequency 540 x 1 012 hertz and that has a radiant intensity in
that direction of l/683 watt per steradian.
[16th CGPM (1979), Resolution 31
22
-
(Continued from second cover)
In term tional Standard
IS0 31-6 : 1992
IS0 31-7 : 1992
IS0 31-8 : 1992
IS0 31-9 : 1992
IS0 31-10: 1992
IS0 31-11 : 1992
IS0 31-12 : 1992
IS0 31-13 : 1992
IS0 2955 : 1983
corresponding Indian Standard
IS 1890 (Part 6) : 1983) Quantities, units and symbols: Part 6
Light and related electromagnetic radiations
IS 1890 (Part 7) : 1994 Quantities and units: Part 7 Acoustics
(first revision)
IS 1890 (Part 8) : 1994 Quantities and units: Part 8 Physical
chemistry and molecular (first revision)
IS 1890 (Part 9) : 1994 Quantities and units: Part 9 Atomicand
nuclear physics (first revision)
IS 1890 (Part 10) : 1994 Quantities and units: Part 10 Nuclear
reactions and ionizing radiation (first revision)
ISl890(Pattll): 1994Quantitiesand units: Part 11 Mathematical
signs and symbols for use in the physical science and technology
(second revision)
IS1890(Part12):1994Quantitiesand units: Part 12 Characteristic
number (first revision)
IS 1890 (Part 13) : 1983l) Quantities, units and symbols: Part
13 Solid state physics
IS 11366 : 1985 Representation of SI and other units in systems
with limited characteristics for information processing
Degree of Equivalence
Technically equivalent
Identical
Identical
Identical
Identical
Identical
Identical
Technically equivalent
Identical
) Under Revision.
-
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Review of Indian Standards
Amendments are issued to standards as the need arises on the
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Standards should ascertain that they are in possession of the
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This Indian Standard has been developed from Dot No. MSD
1(89)
Amendments Issued Since Publication
Amend No. Date of Issue Text Affected
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