Basic Unit	Symbol	Definition
1.	metre	m	the unit for the measurement of length, being a length equal to the distance travelled by light in a vacuum during 1/299 792 458 of a second
2.	kilogram	kg	the unit for the measurement of mass, being a mass equal to the mass of the international prototype of the kilogram established in the year 1889 by the First General Conference of Weights and Measures and deposited at the International Bureau of Weights and Measures
3.	second	s	the unit for the measurement of time, being the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom
4.	ampere	A	the unit for the measurement of electric current, being a constant current that, if maintained in two straight parallel conductors of infinite length, of negligible circular cross­section and placed one metre apart in vacuum, would produce between those conductors a force equal to 2 x 10-7newton per metre of length
5.	kelvin	K	the unit for the measurement of thermodynamic temperature, being the fraction 1/273.16 of the thermodynamic temperature of the triple point of water
6.	candela	cd	the unit for the measurement of luminous intensity, being the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 x 1012hertz and that has a radiant intensity in that direction of 1/683 watt per steradian
7.	mole	mol	the unit for the measurement of the amount of substance, being the amount of substance of a system that contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12

	Supplementary Unit	Symbol	Definition
1.	radian	rad	the unit for the measurement of a plane angle, being the angle with its vertex at the centre of a circle and subtended by an arc of the circle that is equal in length to its radius
2.	steradian	sr	the unit for the measurement of a solid angle, being the angle with its vertex at the centre of a sphere and subtended by an area on the spherical surface equal to that of a square with sides equal in length to the radius

	Derived Unit	Symbol	Definition
1.	newton	N	the force that, when applied to a body having a mass of one kilogram, gives the body an acceleration of one metre per second per second
2.	joule	J	the work done when the point of application of a force of one newton is displaced a distance of one metre in the direction of the force
3.	watt	W	the power that produces energy at the rate of one joule per second
4.	hertz	Hz	the frequency of a periodic phenomenon of which the periodic time is one second
5.	coulomb	C	the quantity of electricity transported in one second by a current of one ampere
6.	volt	V	the unit of electric potential difference and electromotive force, being the difference of electric potential between two equipotential surfaces of a conductor that is carrying a constant current of one ampere when the power dissipated between these surfaces is equal to one watt
7.	farad	F	the capacitance of a capacitor between the equipotential surfaces of which there appears a difference of potential of one volt when the capacitor is charged by a quantity of electricity equal to one coulomb
8.	henry	H	the inductance of a closed circuit in which an electromotive force of one volt is produced when the electric current in the circuit varies uniformly at a rate of one ampere per second
9.	ohm	?	the electric resistance between two points of a conductor when a constant difference of potential of one volt, applied between these two points, produces in the conductor a current of one ampere and the conductor itself is not the seat of any electromotive force
10.	weber	Wb	the magnetic flux that, when linking a circuit of one turn, produces in that circuit an electromotive force of one volt as the flux is reduced to zero at a uniform rate in one second
11.	tesla	T	the magnetic induction that is equal to one weber per square metre
12.	lumen	lm	the luminous flux emitted in a solid angle of one steradian by a point source having an intensity of one candela
13.	lux	lx	the illuminance produced by a flux of one lumen uniformly distributed over one square metre
14.	pascal	Pa	the pressure (or stress) produced when a force of one newton is applied to an area of one square metre
15.	var	var	the reactive power at the two points of entry of a single­phase, two­wire circuit when the product of the root­mean­square value in amperes of the sinusoidal current by the root­mean­square value in volts of the sinusoidal voltage and by the sine of the angular phase difference by which the voltage leads the current is equal to one
16.	becquerel	Bq	the activity of radionuclides that is equal to one per second
17.	gray	Gy	the absorbed dose of ionizing radiation that is equal to one joule per kilogram
18.	siemens	S	the electric conductance between two points of a conductor when a constant current of one ampere in the conductor produces a difference of potential of one volt between these two points and the conductor itself is not the seat of any electromotive force

Customary Unit	Symbol	Definition
minute	min	60 seconds
hour	h	3 600 seconds
day	d	86 400 seconds
degree (of arc)	°	p/180 radian*
minute (of arc)	'	p/10 800 radian*
second (of arc)	"	p/648 000 radian*
litre	L,lor l	1/1 000 cubic metre
tonneormetric ton	t	1 000 kilograms
hectare	ha	104square metres
millilitre	mL, mlor ml	1/1 000 litre
degree Celsius	°C	an interval of 1°C = an interval of 1 kelvin; a temperature of 0°C corresponds to 273.15 kelvins

* p is the ratio of the circumference to the diameter of a circle.

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

* Not applicable to the basic unit “kilogram” but applicable to the one thousandth submultiple of that unit, namely the “gram (g)”.

R.S., 1985, c. W-6, Sch. I; SOR/86-420; SOR/2005–277, ss. 1, 2.

Measurement of Length

Measurement of Area

Measurement of Volume or Capacity

Measurement of Mass or Weight

Measurement of the Mass or Weight of Precious Metals

Measurement of the Mass or Weight of Precious Stones and Gem Stones

R.S., 1985, c. W-6, Sch. II; SOR/86-854.

1970-71-72, c. 36, Sch. III.

1. The national standard for length in Canada realized, through the use of any device, in compliance with the definition “mètre” passed by the 17e Conférence Générale des Poids et Mesures as reported in the Comptes rendus de la 17e Conférence Générale des Poids et Mesures (1983) published by the International Bureau of Weights and Measures, and determined by the National Research Council of Canada pursuant to subparagraph 5(1)(c)(iv) of the National Research Council Act.

Avoirdupois Weight

1. A standard of a nominal mass of one pound, designated MR-2.

Troy Weight

2. A standard of nominal mass of one hundred troy ounces, designated MR-3.

Metric Weight

3. A standard of a nominal mass of one kilogram, designated MR-1.

Item	Standard Number	Description
1.	V5587198	Thermometer, manufactured by Guildline Instruments Ltd. having serial number 55580
2.	V5587199	Thermometer, manufactured by Guildline Instruments Ltd. having serial number 55581
3.	VS767_1203	Thermistor sensor, manufactured by Thermometrics having serial number 1203; and Black Stack thermometer module, manufactured by Hart Scientific having serial number A13108

Item	Standard Number	Description
1.	L­49	Voltage Transformer, manufactured by Smith Hobson Ltd. having serial number 60283
2.	L­181	Voltage Transformer, manufactured by Ferranti Packard Ltd. having serial number 2­19602
3.	L­1046	Voltage Transformer, manufactured by Sangamo Company Limited having serial number 555762
4.	EL­1847	Voltage Transformer, manufactured by Instrument Transformer Inc. having serial number 547222
5.	EL­1848	Voltage Transformer, manufactured by Asea Brown Boveri Ltd. having serial number 39518360
6.	L­516	Current Burden, manufactured by the Legal Metrology Branch, having the operating range of B0.1 to B2.0 and the serial number 001
7.	L­772	Current Transformer Test Set, manufactured by Guildline Instruments Ltd. having serial number 36891/36892
8.	L­919	Current Transformer Range Extender, manufactured by Guildline Instruments Ltd. having serial number 39151
9.	EL­857	Current Transformer, manufactured by Smith Hobson Ltd. having serial number G­033127
10.	EL­1720	Current Transformer, manufactured by Knopp Inc. having serial number 8039391
11.	L­867	Decade Resistor, manufactured by General Radio Canada Ltd. having serial number 28742
12.	EL­1820	Multifunction Transducer (W/WH/VA/VAH/VAR/VARH/V/VH/I/IH) , Radian Metronic model RM­15­14, manufactured by Radian Research Inc. having serial number 4357
13.	EL­1666	Multifunction Micro­Joule Meter (I2+V2hours) , manufactured by Scientific Columbus Ltd. having serial number 6791

Item	Standard Number	Description
1.	L­879	Pi­Tape Linear Measure, manufactured by Collins­Phillips Co. having serial number 0227834
2.	L­880	Pi­Tape Linear Measure, manufactured by Collins­Phillips Co. having serial number 69827
3.	L­881	Pi­Tape Linear Measure, manufactured by Collins­Phillips Co. having serial number 1212810
4.	GL­2033	Dead Weight Tester, manufactured by Ruska Instruments Co. having serial number 44509
5.	GL­2104	Dead Weight Tester, manufactured by Ruska Instruments Co. having serial number 46404

R.S., 1985, c. W-6, Sch. IV; SOR/86-133; SOR/93-235, s. 2; SOR/2000-250; SOR/2005–277, ss. 3, 4.