EDCS Reference Manual

EDCS Reference Manual EDCS Unit Dictionary, EDCS Scale Dictionary, EDCS Unit Equivalence Class Dictionary

EDCS Unit Dictionary
EDCS Scale Dictionary
EDCS Unit Equivalence Class Dictionary

EDCS Unit Dictionary

Jump to units whose label begin with: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

EDCS Unit Label: AMP_PER_METRE

EDCS Unit Symbolic Constant: EUC_AMP_PER_METRE

EDCS Unit Code: 1

Symbol: A/m

EDCS Unit Equivalence Class Label: LINEIC_ELECTRIC_CURRENT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 3

Quantity: lineic electric current (linear electric current density)
Definition: The electric current in a conducting sheet divided by the width of the sheet.
Reference type: PR
Reference: I31-5, 5-16.a
Supplemental References: none

Quantity: magnetic field strength
Definition: A vector quantity, the rotation (curl) of which is equal to the sum of the electric current density and the time derivative of the electric flux density.
Reference type: PR
Reference: I31-5, 5-17.a
Supplemental References: none

Quantity: magnetization
Definition: The extent to which a magnetic material is magnetized, given by the magnetic moment per unit volume.
Reference type: PR
Reference: I31-5, 5-28.a
Supplemental References: none

EDCS Unit Label: AMP_PER_SQ_M_KELVIN_SQD

EDCS Unit Symbolic Constant: EUC_AMP_PER_SQ_M_KELVIN_SQD

EDCS Unit Code: 2

Symbol: A/(m² · K²)

EDCS Unit Equivalence Class Label: THERMION_EMISSION_CUR_DENS

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: thermionic emission current density
Definition: A vector quantity, the integral of whose normal component over a heated surface is equal to the net number of particles (electrons or ions) emitted from that surface, as a function of the thermodynamic temperature of that surface.
Reference type: PR
Reference: I31-13, 13-27.a
Supplemental References: none

EDCS Unit Label: AMP_PER_SQ_METRE

EDCS Unit Symbolic Constant: EUC_AMP_PER_SQ_METRE

EDCS Unit Code: 3

Symbol: A/m²

EDCS Unit Equivalence Class Label: AREIC_ELECTRIC_CURRENT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: areic electric current (electric current density)
Definition: A vector quantity, the integral of whose normal component over a given surface is equal to the electric current flowing through that surface.
Reference type: PR
Reference: I31-5, 5-15.a
Supplemental References: none

EDCS Unit Label: AMPERE

EDCS Unit Symbolic Constant: EUC_AMPERE

EDCS Unit Code: 4

Symbol: A

EDCS Unit Equivalence Class Label: ELECTRIC_CURRENT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 4

Quantity: current linkage
Definition: The net electric conduction current through a closed loop.
Reference type: PR
Reference: I31-5, 5-18.a
Supplemental References: none

Quantity: electric current
Definition: That constant electric 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 10^-7 newton per metre of length.
SI base unit.
Reference type: PR
Reference: I31-0, Table 1
Supplemental References: I31-5, 5-1.a

Quantity: magnetic potential difference
Definition: On a given path, the magnetic potential difference between point 1 and point 2 is the line integral from 1 to 2 of the magnetic field strength along that path.
Reference type: PR
Reference: I31-5, 5-18.a
Supplemental References: none

Quantity: magnetomotive force
Definition: The work required to carry a magnetic pole of unit strength once around a magnetic circuit.
Reference type: PR
Reference: I31-5, 5-18.a
Supplemental References: none

EDCS Unit Label: ANGSTROM

EDCS Unit Symbolic Constant: EUC_ANGSTROM

EDCS Unit Code: 5

Symbol: Å

EDCS Unit Equivalence Class Label: LENGTH

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: length
Definition: ångström; 1 Å = 10^-10 m = 10^-1 nm = 10^-4 μm (exactly).
Reference type: PR
Reference: I31-1, 1-3.a (remarks)
Supplemental References: I1000, Annex A, 6.3

EDCS Unit Label: ARE

EDCS Unit Symbolic Constant: EUC_ARE

EDCS Unit Code: 6

Symbol: a

EDCS Unit Equivalence Class Label: AREA

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: area
Definition: The product of length and width.
1 a = 1 dam² = 10² m² (exactly).
Reference type: PR
Reference: I31-1, 1-5.a (remarks)
Supplemental References: I1000, Annex A, 1-4

EDCS Unit Label: ASTRONOMICAL_UNIT

EDCS Unit Symbolic Constant: EUC_ASTRONOMICAL_UNIT

EDCS Unit Code: 7

Symbol: AU

EDCS Unit Equivalence Class Label: LENGTH

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: length
Definition: 1 AU = 1,495 978 7 x 10¹¹ m (approximately).
Reference type: PR
Reference: I31-1, 1-3.B.b
Supplemental References: none

EDCS Unit Label: BAR

EDCS Unit Symbolic Constant: EUC_BAR

EDCS Unit Code: 8

Symbol: bar

EDCS Unit Equivalence Class Label: PRESSURE

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: pressure
Definition: The force that is exerted per unit area.
1 bar = 10⁵ Pa (exactly).
Reference type: PR
Reference: I31-3, 3-15a (remarks)
Supplemental References: I1000, Annex A, 3-15.1

EDCS Unit Label: BARN

EDCS Unit Symbolic Constant: EUC_BARN

EDCS Unit Code: 9

Symbol: b

EDCS Unit Equivalence Class Label: AREA

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: area
Definition: The product of length and width.
1 b = 100 fm² = 10^-28 m² (exactly).
Reference type: PR
Reference: I31-10, 10-3.a (remarks)
Supplemental References: none

EDCS Unit Label: BECQUEREL

EDCS Unit Symbolic Constant: EUC_BECQUEREL

EDCS Unit Code: 10

Symbol: Bq

EDCS Unit Equivalence Class Label: RADIONUCLIDE_ACTIVITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: activity of a radio nuclide
Definition: The average number of spontaneous nuclear transitions from a particular energy state occurring in an amount of a radionuclide in a small time interval, divided by that interval.
1 Bq = 1 s^-1.
Reference type: PR
Reference: I31-0, Table 3
Supplemental References: I31-9, 9-33.a; I31-10, 10-49.a

EDCS Unit Label: BECQUEREL_PER_CUBIC_METRE

EDCS Unit Symbolic Constant: EUC_BECQUEREL_PER_CUBIC_METRE

EDCS Unit Code: 11

Symbol: Bq/m³

EDCS Unit Equivalence Class Label: VOLUMIC_ACTIVITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: volumic activity (activity concentration)
Definition: Activity of a radionuclide divided by the total volume of the sample.
Reference type: PR
Reference: I31-9, 9-35.a
Supplemental References: none

EDCS Unit Label: BECQUEREL_PER_KG

EDCS Unit Symbolic Constant: EUC_BECQUEREL_PER_KG

EDCS Unit Code: 12

Symbol: Bq/kg

EDCS Unit Equivalence Class Label: MASSIC_ACTIVITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: massic activity (specific activity)
Definition: Activity of a radionuclide divided by the total mass of the sample.
Reference type: PR
Reference: I31-9, 9-34.a
Supplemental References: none

EDCS Unit Label: BEL

EDCS Unit Symbolic Constant: EUC_BEL

EDCS Unit Code: 13

Symbol: B

EDCS Unit Equivalence Class Label: FIELD_OR_POWER_LEVEL_DIFF

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 4

Quantity: field quantity ratio (level difference)
Definition: Twice the common logarithm of a field quantity ratio.
1 B is the level of a field quantity when 2 lg (F/F₀) = 1 where F and F₀ represent two amplitudes of the same kind, F₀ being a reference amplitude.
1 B = (1/2) ln 10 Np = 1,151 293 Np (approximately).
Reference type: PR
Reference: I31-2, 2-9.b
Supplemental References: none

Quantity: power quantity ratio (level difference)
Definition: The common logarithm of a power quantity ratio.
1 B is the level of a power quantity when lg (P/P₀) = 1 where P and P₀ represent two powers, P₀ being a reference power.
Reference type: PR
Reference: I31-2, 2-10.b
Supplemental References: none

Quantity: sound power level
Definition: L_W = 1/2 ln (P/P₀) = 1/2 ln 10·lg (P/P₀) where P is the root-mean-square of the sound power and the reference power p₀ = 1 x 10^-12 W.
Reference type: PR
Reference: I31-7, 7-22.a
Supplemental References: none

Quantity: sound pressure level
Definition: L_p = ln (p/p₀) = ln 10·lg (p/p₀) where p is the root-mean-square value of the sound pressure and the reference pressure p₀ = 20 μPa.
Reference type: PR
Reference: I31-7, 7-21.a
Supplemental References: none

EDCS Unit Label: CANDELA

EDCS Unit Symbolic Constant: EUC_CANDELA

EDCS Unit Code: 14

Symbol: cd

EDCS Unit Equivalence Class Label: LUMINANCE_INTENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: luminous intensity
Definition: The luminous intensity, in a given direction, of a source that emits monochromatic radiation of a frequency 540 x 10¹² Hertz, and that has a radiant intensity in that direction of 1 / 683 watt per steradian.
SI base unit.
Reference type: PR
Reference: I31-0, Table 1
Supplemental References: I31-6, 6-29.a

EDCS Unit Label: CD_PER_SQ_METRE

EDCS Unit Symbolic Constant: EUC_CD_PER_SQ_METRE

EDCS Unit Code: 15

Symbol: cd/m²

EDCS Unit Equivalence Class Label: LUMINANCE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: luminance
Definition: At a point on a surface and in a given direction, the luminous intensity of an element of the surface, divided by the area of the orthogonal projection of this element on a plane perpendicular to the given direction.
Reference type: PR
Reference: I31-6, 6-32.a
Supplemental References: none

EDCS Unit Label: COULOMB

EDCS Unit Symbolic Constant: EUC_COULOMB

EDCS Unit Code: 16

Symbol: C

EDCS Unit Equivalence Class Label: ELECTRIC_CHARGE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 3

Quantity: electric charge (quantity of electricity)
Definition: The integral of electric current over time.
1 C = 1 s · A.
Reference type: PR
Reference: I31-0, Table 2
Supplemental References: I31-5, 5-2.a

Quantity: electric flux
Definition: Across a surface element, the scalar product of the electric flux density and the surface element.
Reference type: PR
Reference: I31-5, 5-8.a
Supplemental References: none

Quantity: elementary charge
Definition: The electric charge of a proton.
Reference type: PR
Reference: I31-9, 9-6.a
Supplemental References: I31-8, 8-43.a

EDCS Unit Label: COULOMB_METRE

EDCS Unit Symbolic Constant: EUC_COULOMB_METRE

EDCS Unit Code: 17

Symbol: C · m

EDCS Unit Equivalence Class Label: ELECTRIC_DIPOLE_MOMENT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: electric dipole moment
Definition: A vector quantity, the vector product of which with the electric field strength of a homogenous field is equal to the torque.
1 C · m = 1 m · s · A.
Reference type: PR
Reference: I31-5, 5-14.a
Supplemental References: none

Quantity: electric dipole moment of a molecule
Definition: A vector quantity, the vector product of which with the electric field strength is equal to the torque.
Reference type: PR
Reference: I31-8, 8-32.a
Supplemental References: none

EDCS Unit Label: COULOMB_METRE_SQD_PER_VOLT

EDCS Unit Symbolic Constant: EUC_COULOMB_METRE_SQD_PER_VOLT

EDCS Unit Code: 18

Symbol: C · m²/V

EDCS Unit Equivalence Class Label: ELECTRIC_POLARIZABILITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: electric polarizability of a molecule
Definition: The induced electric dipole moment divided by electric field strength.
1 C · m²/V = 1 (s⁴ · A²)/kg.
Reference type: PR
Reference: I31-8, 8-33.a
Supplemental References: none

EDCS Unit Label: COULOMB_PER_CUBIC_M

EDCS Unit Symbolic Constant: EUC_COULOMB_PER_CUBIC_M

EDCS Unit Code: 19

Symbol: C/m³

EDCS Unit Equivalence Class Label: VOLUME_DENSITY_CHARGE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: volume charge (volume density of charge, electric charge density)
Definition: The charge divided by volume.
1 C/m³ = 1 (s · A)/m³.
Reference type: PR
Reference: I31-5, 5-3.a
Supplemental References: none

EDCS Unit Label: COULOMB_PER_KG

EDCS Unit Symbolic Constant: EUC_COULOMB_PER_KG

EDCS Unit Code: 20

Symbol: C/kg

EDCS Unit Equivalence Class Label: EXPOSURE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: exposure of ionizing radiation
Definition: The total electric charge of the ions of the same sign produced when all the electrons (negative and positive) liberated by photons in an element of air are stopped in air, divided by the mass of that element.
1 C/kg = 1 (s · A)/kg.
Reference type: PR
Reference: I31-10, 10-58.a
Supplemental References: none

EDCS Unit Label: COULOMB_PER_KG_SEC

EDCS Unit Symbolic Constant: EUC_COULOMB_PER_KG_SEC

EDCS Unit Code: 21

Symbol: C/(kg · s)

EDCS Unit Equivalence Class Label: EXPOSURE_RATE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: exposure rate of ionizing radiation
Definition: The exposure (ionizing radiation) divided by time.
1 C/(kg · s) = 1 A/kg.
Reference type: PR
Reference: I31-10, 10-59.a
Supplemental References: none

EDCS Unit Label: COULOMB_PER_MOLE

EDCS Unit Symbolic Constant: EUC_COULOMB_PER_MOLE

EDCS Unit Code: 22

Symbol: C/mol

EDCS Unit Equivalence Class Label: MOLAR_CHARGE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: molar charge
Definition: The charge carried per amount of substance.
1 C/mol = 1 (s · A)/mol.
Reference type: PR
Reference: I31-8, 8-45.a
Supplemental References: none

EDCS Unit Label: COULOMB_PER_SQ_M

EDCS Unit Symbolic Constant: EUC_COULOMB_PER_SQ_M

EDCS Unit Code: 23

Symbol: C/m²

EDCS Unit Equivalence Class Label: SURFACE_DENSITY_CHARGE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 3

Quantity: areic charge (surface density of charge)
Definition: The charge divided by surface area.
1 C/m² = 1 (s · A)/m².
Reference type: PR
Reference: I31-5, 5-4.a
Supplemental References: none

Quantity: electric flux density
Definition: A vector quantity, the divergence of which is equal to the volumic charge.
Reference type: PR
Reference: I31-5, 5-7.a
Supplemental References: none

Quantity: electric polarization
Definition: A vector quantity equal to the electric dipole moment per unit volume of a material.
Reference type: PR
Reference: I31-5, 5-13.a
Supplemental References: none

EDCS Unit Label: CUBIC_M_PER_CUBIC_M

EDCS Unit Symbolic Constant: EUC_CUBIC_M_PER_CUBIC_M

EDCS Unit Code: 24

Symbol: m³/m³

EDCS Unit Equivalence Class Label: VOLUME_FRACTION

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: volume fraction (of B)
Definition: The volume of B divided by the volume of the mixture.
1 m³/m³ = 1.
Reference type: PR
Reference: I31-8, 8-15.a
Supplemental References: I31-0, 2.3.3

EDCS Unit Label: CUBIC_METRE

EDCS Unit Symbolic Constant: EUC_CUBIC_METRE

EDCS Unit Code: 25

Symbol: m³

EDCS Unit Equivalence Class Label: VOLUME

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: section modulus
Definition: The section modulus of a plane area (section) about an axis in its plane is the second moment of area divided by the distance from the axis to the most remote point of the area.
Reference type: PR
Reference: I31-3, 3-21.a
Supplemental References: none

Quantity: volume
Definition: The product of length, width and height.
Reference type: PR
Reference: I31-1, 1-6.a
Supplemental References: none

EDCS Unit Label: CUBIC_METRE_PER_COULOMB

EDCS Unit Symbolic Constant: EUC_CUBIC_METRE_PER_COULOMB

EDCS Unit Code: 26

Symbol: m³/C

EDCS Unit Equivalence Class Label: RECIPROCAL_VOLUMIC_CHARGE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: reciprocal volumic charge (reciprocal charge density)
Definition: The volume divided by the charge.
Reference type: PR
Reference: I31-13, 13-20.a
Supplemental References: none

EDCS Unit Label: CUBIC_METRE_PER_KG

EDCS Unit Symbolic Constant: EUC_CUBIC_METRE_PER_KG

EDCS Unit Code: 27

Symbol: m³/kg

EDCS Unit Equivalence Class Label: SPECIFIC_VOLUME

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: specific volume
Definition: The volume divided by mass.
Reference type: PR
Reference: I31-3, 3-4.a
Supplemental References: none

EDCS Unit Label: CUBIC_METRE_PER_MOLE

EDCS Unit Symbolic Constant: EUC_CUBIC_METRE_PER_MOLE

EDCS Unit Code: 28

Symbol: m³/mol

EDCS Unit Equivalence Class Label: MOLAR_VOLUME

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: molar volume
Definition: The volume divided by the amount of substance.
Reference type: PR
Reference: I31-8, 8-6.a
Supplemental References: none

EDCS Unit Label: CUBIC_METRE_PER_SEC

EDCS Unit Symbolic Constant: EUC_CUBIC_METRE_PER_SEC

EDCS Unit Code: 29

Symbol: m³/s

EDCS Unit Equivalence Class Label: VOLUME_FLOW_RATE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: recombination coefficient
Definition: The coefficient in the law of recombination.
Reference type: PR
Reference: I31-10, 10-28.a
Supplemental References: none

Quantity: volume flow rate
Definition: The volume of matter which crosses a given surface, divided by time.
Reference type: PR
Reference: I31-3, 3-30.a
Supplemental References: I31-7, 7-13.a

EDCS Unit Label: CURIE

EDCS Unit Symbolic Constant: EUC_CURIE

EDCS Unit Code: 30

Symbol: Ci

EDCS Unit Equivalence Class Label: RADIONUCLIDE_ACTIVITY

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: activity of a radio nuclide
Definition: The average number of spontaneous nuclear transitions from a particular energy state occurring in an amount of a radionuclide in a small time interval, divided by that interval.
1 Ci = 3.7 x 10¹⁰ Bq (exactly).
Reference type: PR
Reference: I31-9, 9-33.a (remarks)
Supplemental References: I1000, Annex A, 9-33

EDCS Unit Label: DAY

EDCS Unit Symbolic Constant: EUC_DAY

EDCS Unit Code: 31

Symbol: d

EDCS Unit Equivalence Class Label: TIME

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: time
Definition: 1 d = 24 h = 86 400 s (exactly).
Reference type: PR
Reference: I31-0, Table 4
Supplemental References: I31-1, 1-7.d

EDCS Unit Label: DB

EDCS Unit Symbolic Constant: EUC_DB

EDCS Unit Code: 32

Symbol: dB

EDCS Unit Equivalence Class Label: FIELD_OR_POWER_LEVEL_DIFF

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: field quantity ratio (level difference)
Definition: A dimensionless quantity used to describe a comparison of field levels.
1 dB = 10^-1 B (exactly) = 1,151 293 x 10^-1Np (approximately).
Reference type: PR
Reference: I31-2, 2-9.a (remarks)
Supplemental References: none

Quantity: power quantity ratio (level difference)
Definition: A dimensionless quantity used to describe a comparison of power levels.
1 dB = 10^-1 B (exactly) = 1,151 293 x 10^-1Np (approximately).
Reference type: PR
Reference: I31-2, 2-10.a (remarks)
Supplemental References: I1000, Annex A, 7-21

EDCS Unit Label: DB_PER_METRE

EDCS Unit Symbolic Constant: EUC_DB_PER_METRE

EDCS Unit Code: 33

Symbol: dB/m

EDCS Unit Equivalence Class Label: POWER_LEVEL_DIFF_LEN_GRADIENT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: power ratio (level difference) gradient
Definition: The rate of power ratio change as a function of distance.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: DB_PER_METRE_KHZ

EDCS Unit Symbolic Constant: EUC_DB_PER_METRE_KHZ

EDCS Unit Code: 34

Symbol: dB/(m · kHz)

EDCS Unit Equivalence Class Label: POWER_LEVEL_DIFF_LEN_FREQ

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: power ratio (level difference) distance and frequency gradient
Definition: The rate of power ratio change as a function of distance and spectral frequency.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: DB_PER_OCTAVE

EDCS Unit Symbolic Constant: EUC_DB_PER_OCTAVE

EDCS Unit Code: 35

Symbol: none

EDCS Unit Equivalence Class Label: POWER_LEVEL_DIFF_FREQ_GRADIENT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: power ratio (level difference) frequency gradient
Definition: The rate of power ratio change as a function of spectral frequency octave.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: DB_PER_SQ_METRE

EDCS Unit Symbolic Constant: EUC_DB_PER_SQ_METRE

EDCS Unit Code: 36

Symbol: dB/m²

EDCS Unit Equivalence Class Label: AREIC_POWER_LEVEL_DIFF

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: areic power ratio (level difference)
Definition: The power level divided by area.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: DB_PER_SQ_METRE_KHZ

EDCS Unit Symbolic Constant: EUC_DB_PER_SQ_METRE_KHZ

EDCS Unit Code: 37

Symbol: dB/(m² · kHz)

EDCS Unit Equivalence Class Label: GRAD_POWER_LEVEL_DIFF_LEN_FREQ

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: gradient of power ratio (level difference) distance and frequency gradient
Definition: The rate of change of power ratio change as a function of distance and spectral frequency.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: DB_REF_ONE_MICROPASCAL

EDCS Unit Symbolic Constant: EUC_DB_REF_ONE_MICROPASCAL

EDCS Unit Code: 38

Symbol: dB (re 1 μPa)

EDCS Unit Equivalence Class Label: PRESSURE_POWER_LEVEL

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: pressure power quantity ratio (level)
Definition: 1 dB (re 1 μPa) is the level of a pressure power quantity when lg (P/P₀) = 0,1 where P and P₀ represent two pressure powers, P₀ being a reference power of 1 μPa.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: DECAY_RATE

EDCS Unit Symbolic Constant: EUC_DECAY_RATE

EDCS Unit Code: 39

Symbol: %/min

EDCS Unit Equivalence Class Label: RATE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: decay constant (disintegration constant)
Definition: Probability of decay of an active species in a small time interval, divided by that interval.
1 %/min = 1 / 6 x 10^-3 1/s (exactly).
Reference type: PR
Reference: I31-9, 9-36.a
Supplemental References: I31-0, 2.3.2.3

EDCS Unit Label: DEGREE_ARC

EDCS Unit Symbolic Constant: EUC_DEGREE_ARC

EDCS Unit Code: 40

Symbol: °

EDCS Unit Equivalence Class Label: PLANE_ANGLE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: Bragg angle
Definition: The angle between an incident X-ray beam and a set of crystal planes for which the secondary radiation displays maximum intensity as a result of constructive interference.
Reference type: PR
Reference: I31-13, 13-4.b
Supplemental References: none

Quantity: plane angle
Definition: The angle between two half-lines terminating at the same point is defined as the ratio of the length of the included arc of the circle (with its centre at that point) to the radius of that circle.
1° = (π / 180) rad (exactly).
Reference type: PR
Reference: I31-0, Table 4
Supplemental References: I31-1, 1-1.b

EDCS Unit Label: DEGREE_C

EDCS Unit Symbolic Constant: EUC_DEGREE_C

EDCS Unit Code: 41

Symbol: °C

EDCS Unit Equivalence Class Label: THERMO_TEMPERATURE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: thermodynamic temperature
Definition: A special name for the kelvin for use in stating values of Celsius temperature.
t = T - T₀ where T₀ = 273,15 K (exactly).
Reference type: PR
Reference: I31-0, Table 2
Supplemental References: I31-4, 4-2.a

EDCS Unit Label: DEGREE_C_PER_HOUR

EDCS Unit Symbolic Constant: EUC_DEGREE_C_PER_HOUR

EDCS Unit Code: 42

Symbol: °C/h

EDCS Unit Equivalence Class Label: THERMO_TEMP_CHANGE_RATE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: thermodynamic temperature change rate
Definition: The thermodynamic temperature change over an interval of time, divided by that time.
1 °C/h = 1 / 3,6 x 10^-3 K/s (exactly).
Reference type: PR
Reference: I31-0, 2.3.2.2 and 2.3.4 (derived)
Supplemental References: none

EDCS Unit Label: DEGREE_C_PER_METRE

EDCS Unit Symbolic Constant: EUC_DEGREE_C_PER_METRE

EDCS Unit Code: 43

Symbol: °C/m

EDCS Unit Equivalence Class Label: LINEIC_THERMO_TEMP_GRADIENT

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: lineic thermodynamic temperature gradient
Definition: The thermodynamic temperature change over a distance, divided by that distance.
1 °C/m = 1 K/m (exactly).
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: DEGREE_C_PER_SEC

EDCS Unit Symbolic Constant: EUC_DEGREE_C_PER_SEC

EDCS Unit Code: 44

Symbol: °C/s

EDCS Unit Equivalence Class Label: THERMO_TEMP_CHANGE_RATE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: thermodynamic temperature change rate
Definition: The thermodynamic temperature change over an interval of time, divided by that time.
1 °C/s = 1 K/s (exactly).
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: ELECTRONVOLT

EDCS Unit Symbolic Constant: EUC_ELECTRONVOLT

EDCS Unit Code: 45

Symbol: eV

EDCS Unit Equivalence Class Label: ENERGY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 12

Quantity: alpha disintegration energy
Definition: The sum of the kinetic energy of the alpha particle produced in the disintegration process and the recoil energy of the product atom in the reference frame in which the emitting nucleus is at rest before its disintegration.
Reference type: PR
Reference: I31-9, 9-38.b
Supplemental References: none

Quantity: average energy loss per ion pair formed (average energy loss per elementary charge of the same sign produced)
Definition: The initial kinetic energy of an ionizing charged particle, divided by the total ionization produced by that particle.
Reference type: PR
Reference: I31-10, 10-25.b
Supplemental References: none

Quantity: beta disintegration energy
Definition: Sum of the maximum beta particle energy and the recoil energy of the atom produced in the reference frame in which the emitting nucleus is at rest before its disintegration.
Reference type: PR
Reference: I31-9, 9-40.b
Supplemental References: none

Quantity: electron affinity
Definition: The energy difference between an electron at rest at infinity and an electron at the lowest level of the conduction band in an insulator or semiconductor.
Reference type: PR
Reference: I31-13, 13-26.b
Supplemental References: none

Quantity: energy
Definition: The kinetic energy acquired by an electron in passing through a potential difference of 1 volt in a vacuum. Its value is experimentally determined as 1,602 177 x 10^-19 J (approximately).
Reference type: PR
Reference: I31-0, Table 6
Supplemental References: I31-9, 9-32.b

Quantity: exchange integral
Definition: The interaction energy arising from electron exchange.
Reference type: PR
Reference: I31-13, 13-35.b
Supplemental References: none

Quantity: Fermi energy
Definition: In a metal, the highest energy of occupied states at zero thermodynamic temperature.
Reference type: PR
Reference: I31-13, 13-28.b
Supplemental References: none

Quantity: gap energy
Definition: Difference in energy between lowest level of conduction band and highest level of valence band.
Reference type: PR
Reference: I31-13, 13-28.b
Supplemental References: none

Quantity: maximum beta particle energy
Definition: Maximum energy of the energy spectrum in a beta disintegration process.
Reference type: PR
Reference: I31-9, 9-39.b
Supplemental References: none

Quantity: reaction energy
Definition: In a nuclear reaction, the sum of the kinetic and photon energies of the reaction products minus the sum of the kinetic and photon energies of the reactants.
Reference type: PR
Reference: I31-10, 10-1.b
Supplemental References: none

Quantity: resonance energy
Definition: Kinetic energy of an incident particle, in the reference frame of the target, corresponding to a resonance in a nuclear reaction.
Reference type: PR
Reference: I31-10, 10-2.b
Supplemental References: none

Quantity: work function
Definition: The energy difference between an electron at rest at infinity and an electron at the Fermi level in the interior of a substance.
Reference type: PR
Reference: I31-13, 13-25.b
Supplemental References: none

EDCS Unit Label: ELECTRONVOLT_M_SQD

EDCS Unit Symbolic Constant: EUC_ELECTRONVOLT_M_SQD

EDCS Unit Code: 46

Symbol: eV · m²

EDCS Unit Equivalence Class Label: TOTAL_ATOMIC_STOPPING_POWER

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: total atomic stopping power
Definition: The total linear stopping power divided by the number density of the atoms in the substance.
1 eV · m² = (1,602 177 33 ± 0,000 000 49) x 10^-19 J · m² (approximately).
Reference type: PR
Reference: I31-10, 10-19.b
Supplemental References: none

EDCS Unit Label: ELECTRONVOLT_M_SQD_PER_KG

EDCS Unit Symbolic Constant: EUC_ELECTRONVOLT_M_SQD_PER_KG

EDCS Unit Code: 47

Symbol: (eV · m²)/kg

EDCS Unit Equivalence Class Label: TOTAL_MASS_STOPPING_POWER

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: total mass stopping power
Definition: The total linear stopping power divided by the volumic mass of the substance.
1 (eV · m²)/kg = (1,602 177 33 ± 0,000 000 49) x 10^-19 (J · m²)/kg (approximately).
Reference type: PR
Reference: I31-10, 10-20.b
Supplemental References: none

EDCS Unit Label: ELECTRONVOLT_PER_METRE

EDCS Unit Symbolic Constant: EUC_ELECTRONVOLT_PER_METRE

EDCS Unit Code: 48

Symbol: eV/m

EDCS Unit Equivalence Class Label: TOTAL_LINEAR_STOPPING_POWER

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: linear energy transfer
Definition: For an ionizing charged particle, the energy imparted locally to matter in traversing a small distance through the matter, divided by that distance.
Reference type: PR
Reference: I31-10, 10-54.b
Supplemental References: none

Quantity: total linear stopping power
Definition: For an ionizing charged particle, the energy imparted locally to matter in traversing a small distance through the matter, divided by that distance; -dE/dx.
1 eV/m = (1,602 177 33 ± 0,000 000 49) x 10^-19 J/m (approximately).
Reference type: PR
Reference: I31-10, 10-18.b
Supplemental References: none

EDCS Unit Label: FARAD

EDCS Unit Symbolic Constant: EUC_FARAD

EDCS Unit Code: 49

Symbol: F

EDCS Unit Equivalence Class Label: CAPACITANCE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: capacitance
Definition: The charge divided by potential difference.
1 F = 1 C/V = 1 (s⁴ · A²)/(m² · kg).
Reference type: PR
Reference: I31-0, Table 2
Supplemental References: I31-5, 5-9.a

EDCS Unit Label: FARAD_PER_METRE

EDCS Unit Symbolic Constant: EUC_FARAD_PER_METRE

EDCS Unit Code: 50

Symbol: F/m

EDCS Unit Equivalence Class Label: PERMITTIVITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: permittivity
Definition: The ability of a material to resist the formation of an electric field within it.
1 F/m = 1 (s⁴ · A²)/(m³ · kg).
Reference type: PR
Reference: I31-5, 5-10.a
Supplemental References: none

EDCS Unit Label: FOOT

EDCS Unit Symbolic Constant: EUC_FOOT

EDCS Unit Code: 51

Symbol: ft

EDCS Unit Equivalence Class Label: LENGTH

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: length
Definition: 1 ft = 0,304 8 m (exactly).
Reference type: PR
Reference: I31-1, 1-3.A.b
Supplemental References: none

EDCS Unit Label: GAL

EDCS Unit Symbolic Constant: EUC_GAL

EDCS Unit Code: 52

Symbol: Gal

EDCS Unit Equivalence Class Label: ACCELERATION

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: acceleration
Definition: The change in velocity divided by time.
1 Gal = 0,01 m/s² (exactly).
Reference type: PR
Reference: I31-1, 1-11.B.a
Supplemental References: none

EDCS Unit Label: GEOPOTENTIAL_METRE

EDCS Unit Symbolic Constant: EUC_GEOPOTENTIAL_METRE

EDCS Unit Code: 53

Symbol: gpm

EDCS Unit Equivalence Class Label: GEOPOTENTIAL_ENERGY_LENGTH

Unit Status: Not in the scope of SI

Number of quantities which this unit of measure may represent:: 1

Quantity: geopotential energy height (geopotential specific energy)
Definition: A height proportional to the potential energy of mass (geopotential) at this height relative to the geoid.
The geopotential metre varies with geodetic latitude. On <EARTH> at mid-latitudes it equals 0,98 m (approximately).
Reference type: IR
Reference: [WMO182, "geopotential altitude"]
Supplemental References: none

EDCS Unit Label: GON

EDCS Unit Symbolic Constant: EUC_GON

EDCS Unit Code: 54

Symbol: gon

EDCS Unit Equivalence Class Label: PLANE_ANGLE

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: plane angle
Definition: The angle between two half-lines terminating at the same point is defined as the ratio of the length of the included arc of the circle (with its centre at that point) to the radius of that circle.
1 gon = π / 200 rad = 0,015 707 96 rad (exactly).
Reference type: PR
Reference: I31-1, 1-1.B.a
Supplemental References: I1000, Annex A, 1-1

EDCS Unit Label: GRAM

EDCS Unit Symbolic Constant: EUC_GRAM

EDCS Unit Code: 55

Symbol: g

EDCS Unit Equivalence Class Label: MASS

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: mass
Definition: For historical reasons the name of the base unit for mass, the kg, contains the name of the SI prefix "kilo".
A gram is a special name given to unit kg x 10^-3 that is used instead of "millikilogram".
Reference type: PR
Reference: I31-0, 3.2.4
Supplemental References: none

EDCS Unit Label: GRAM_PER_CUBIC_CM

EDCS Unit Symbolic Constant: EUC_GRAM_PER_CUBIC_CM

EDCS Unit Code: 56

Symbol: g/cm³

EDCS Unit Equivalence Class Label: VOLUMIC_MASS

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: mass concentration (of B)
Definition: The amount of substance of B divided by the volume of the mixture.
Reference type: PR
Reference: I31-8, 8-11.a
Supplemental References: none

Quantity: volumic mass (mass density)
Definition: The mass divided by the volume.
1 g/cm³ = 10³ kg/m³ (exactly).
Reference type: PR
Reference: I31-3, 3-2.b
Supplemental References: I31-0, 2.3.2.3; I31-7, 7-8.a

EDCS Unit Label: GRAM_PER_CUBIC_M

EDCS Unit Symbolic Constant: EUC_GRAM_PER_CUBIC_M

EDCS Unit Code: 57

Symbol: g/m³

EDCS Unit Equivalence Class Label: VOLUMIC_MASS

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: mass concentration (of B)
Definition: The amount of substance of B divided by the volume of the mixture.
Reference type: PR
Reference: I31-8, 8-11.a
Supplemental References: none

Quantity: volumic mass (mass density)
Definition: The mass divided by the volume.
1 g/m³ = 10^-3 kg/m³ (exactly).
Reference type: PR
Reference: I31-3, 3-2.b
Supplemental References: I31-0, 2.3.2.3; I31-7, 7-8.a

EDCS Unit Label: GRAM_PER_GRAM

EDCS Unit Symbolic Constant: EUC_GRAM_PER_GRAM

EDCS Unit Code: 58

Symbol: g/g

EDCS Unit Equivalence Class Label: MASS_FRACTION

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: mass fraction (of B)
Definition: The mass of B divided by the mass of the mixture.
1 g/g = 1 kg/kg = 1.
Reference type: PR
Reference: I31-8, 8-12.a
Supplemental References: I31-0, 2.3.3; I31-0, 2.3.2.3

EDCS Unit Label: GRAM_PER_KILOGRAM

EDCS Unit Symbolic Constant: EUC_GRAM_PER_KILOGRAM

EDCS Unit Code: 59

Symbol: g/kg

EDCS Unit Equivalence Class Label: MASS_FRACTION

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: mass fraction (of B)
Definition: The mass of B divided by the mass of the mixture.
1 g/kg = 10^-3 kg/kg = 10^-3 (exactly).
Reference type: PR
Reference: I31-8, 8-12.a
Supplemental References: I31-0, 2.3.3; I31-0, 2.3.2.3

EDCS Unit Label: GRAY

EDCS Unit Symbolic Constant: EUC_GRAY

EDCS Unit Code: 60

Symbol: Gy

EDCS Unit Equivalence Class Label: ABSORBED_DOSE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: absorbed dose of ionizing radiation
Definition: For any ionizing radiation, the energy imparted to an element of irradiated matter divided by the mass of this element.
1 Gy = 1 J/kg = 1 m²/s².
Reference type: PR
Reference: I31-0, Table 3
Supplemental References: I31-10, 10-51.a

Quantity: kerma
Definition: For indirectly ionizing (uncharged) particles, the sum of the initial kinetic energies of all charged particles liberated in an element of matter, divided by the mass of that element.
Reference type: PR
Reference: I31-10, 10-55.a
Supplemental References: none

EDCS Unit Label: GRAY_PER_SECOND

EDCS Unit Symbolic Constant: EUC_GRAY_PER_SECOND

EDCS Unit Code: 61

Symbol: Gy/s

EDCS Unit Equivalence Class Label: ABSORBED_DOSE_RATE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: absorbed dose rate of ionizing radiation
Definition: The absorbed dose of ionizing radiation over an interval of time, divided by that time.
1 Gy/s = 1 W/kg = 1 m²/s³.
Reference type: PR
Reference: I31-10, 10-53.a
Supplemental References: none

Quantity: kerma rate
Definition: For indirectly ionizing (uncharged) particles, the sum of the initial kinetic energies of all charged particles liberated in an element of matter in a small interval of time, divided by the mass of that element and the interval of time.
Reference type: PR
Reference: I31-10, 10-56.a
Supplemental References: none

EDCS Unit Label: HECTARE

EDCS Unit Symbolic Constant: EUC_HECTARE

EDCS Unit Code: 62

Symbol: ha

EDCS Unit Equivalence Class Label: AREA

Unit Status: Deprecated

Number of quantities which this unit of measure may represent:: 1

Quantity: area
Definition: The product of length and width.
1 ha = 1 hm² = 10⁴ m² (exactly).
Reference type: PR
Reference: I31-1, 1-5.a (remarks)
Supplemental References: none

EDCS Unit Label: HENRY

EDCS Unit Symbolic Constant: EUC_HENRY

EDCS Unit Code: 63

Symbol: H

EDCS Unit Equivalence Class Label: INDUCTANCE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: magnetic inductance
Definition: For a thin conducting loop, the magnetic flux through the loop, caused by an electric current in the loop, divided by that current.
For two thin conducting loops (m and n), the magnetic flux through one loop, due to an electric current in the other loop, divided by that current.
1 H = 1 Wb/A = 1 (m² · kg)/(s² · A²).
Reference type: PR
Reference: I31-0, Table 2
Supplemental References: I31-5, 5-22.a

Quantity: permeance
Definition: The reciprocal of the reluctance of a magnetic circuit, determined by the magnetic flux divided by the magnetomotive force.
Reference type: PR
Reference: I31-5, 5-39.a
Supplemental References: none

EDCS Unit Label: HENRY_PER_METRE

EDCS Unit Symbolic Constant: EUC_HENRY_PER_METRE

EDCS Unit Code: 64

Symbol: H/m

EDCS Unit Equivalence Class Label: MAGNETIC_PERMEABILITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: magnetic permeability
Definition: The ability of a substance to acquire magnetization when placed in a magnetic field.
1 H/m = 1 (m · kg)/(s² · A²).
Reference type: PR
Reference: I31-5, 5-24.a
Supplemental References: none

EDCS Unit Label: HERTZ

EDCS Unit Symbolic Constant: EUC_HERTZ

EDCS Unit Code: 65

Symbol: Hz

EDCS Unit Equivalence Class Label: FREQUENCY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: frequency
Definition: The number of cycles divided by time.
1 Hz = 1 s^-1.
Reference type: PR
Reference: I31-0, Table 2
Supplemental References: I31-2, 2-3.a; I31-6, 6-1.a; I31-7, 7-2.a

Quantity: rotational frequency
Definition: The number of revolutions divided by time.
1 Hz = 1 s^-1.
Reference type: PR
Reference: I31-5, 5-41.a
Supplemental References: none

EDCS Unit Label: HOUR

EDCS Unit Symbolic Constant: EUC_HOUR

EDCS Unit Code: 66

Symbol: h

EDCS Unit Equivalence Class Label: TIME

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: time
Definition: 1 h = 60 min = 3 600 s (exactly).
Reference type: PR
Reference: I31-0, Table 4
Supplemental References: I31-1, 1-7.c

EDCS Unit Label: INT_SOLAR_FLUX_UNIT

EDCS Unit Symbolic Constant: EUC_INT_SOLAR_FLUX_UNIT

EDCS Unit Code: 67

Symbol: none

EDCS Unit Equivalence Class Label: FLUX_DENSITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: international solar flux unit
Definition: The unit of radio emission from the <SUN>, measured at a wavelength of 10.7 cm (approximately 2 800 MHz).
1 SFU = 10⁴ Jy = 10^-22 W/(m² · Hz) (exactly).
Reference type: PR
Reference: I31-0, 2.3.1 and 2.3.2 (derived)
Supplemental References: none

EDCS Unit Label: INV_CUBIC_CM

EDCS Unit Symbolic Constant: EUC_INV_CUBIC_CM

EDCS Unit Code: 68

Symbol: 1/cm³

EDCS Unit Equivalence Class Label: VOLUMETRIC_ENTITY_DENSITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: volumetric entity density (any elementary entity: atoms, molecules, ions, electrons, other particles, or specified groups of such particles)
Definition: The number of molecules or particles divided by volume.
1/cm³ = 10^-6 1/m³.
Reference type: PR
Reference: I31-10, 10-27.a
Supplemental References: I31-0, 2.3.2.3

EDCS Unit Label: INV_CUBIC_CM_SEC

EDCS Unit Symbolic Constant: EUC_INV_CUBIC_CM_SEC

EDCS Unit Code: 69

Symbol: 1/(cm³ · s)

EDCS Unit Equivalence Class Label: VOLUMETRIC_ENTITY_EMIT_RATE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: volumetric entity emittance or capture rate (any elementary entity: atoms, molecules, ions, electrons, other particles, or specified groups of such particles)
Definition: The number of molecules or particles divided by volume, per time.
1/(cm³ · s) = 10^-6 1/(m³ · s).
Reference type: PR
Reference: I31-10, 10-35.a
Supplemental References: I31-0, 2.3.2.3

EDCS Unit Label: INV_CUBIC_METRE

EDCS Unit Symbolic Constant: EUC_INV_CUBIC_METRE

EDCS Unit Code: 70

Symbol: 1/m³

EDCS Unit Equivalence Class Label: VOLUMETRIC_ENTITY_DENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 4

Quantity: electron number density (volumic electron number)
Definition: The number density of electrons in conduction band.
Reference type: PR
Reference: I31-13, 13-30.a
Supplemental References: none

Quantity: ion number density (ion density)
Definition: The number of positive or negative ions in a volume element, divided by that element.
Reference type: PR
Reference: I31-10, 10-27.a
Supplemental References: none

Quantity: neutron number density
Definition: The number of free neutrons in a volume element, divided by that element.
Reference type: PR
Reference: I31-10, 10-29.a
Supplemental References: none

Quantity: volumetric entity density (any elementary entity: atoms, molecules, ions, electrons, other particles, or specified groups of such particles)
Definition: The number of molecules or particles divided by their volume.
Reference type: PR
Reference: I31-8, 8-10.a
Supplemental References: none

EDCS Unit Label: INV_CUBIC_METRE_EV

EDCS Unit Symbolic Constant: EUC_INV_CUBIC_METRE_EV

EDCS Unit Code: 71

Symbol: 1/(m³ · eV)

EDCS Unit Equivalence Class Label: DENSITY_STATES

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: density of states
Definition: A function of the energy in a solid given by the number of permitted quantum states in the energy range between E and E + dE, per unit volume of the material.
1/(m³ · eV) = (6,241 5061 4 ± 0,0001 0011 9) x 10¹⁸ 1/(m³ · J) (approximately).
Reference type: PR
Reference: I31-13, 13-17.b
Supplemental References: none

EDCS Unit Label: INV_CUBIC_METRE_JOULE

EDCS Unit Symbolic Constant: EUC_INV_CUBIC_METRE_JOULE

EDCS Unit Code: 72

Symbol: 1/(m³ · J)

EDCS Unit Equivalence Class Label: DENSITY_STATES

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: density of states
Definition: A function of the energy in a solid given by the number of permitted quantum states in the energy range between E and E + dE, per unit volume of the material.
Reference type: PR
Reference: I31-13, 13-17.a
Supplemental References: none

EDCS Unit Label: INV_CUBIC_METRE_SEC

EDCS Unit Symbolic Constant: EUC_INV_CUBIC_METRE_SEC

EDCS Unit Code: 73

Symbol: 1/(m³ · s)

EDCS Unit Equivalence Class Label: VOLUMETRIC_ENTITY_EMIT_RATE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: slowing-down density
Definition: The number density of neutrons slowing down past a given energy value in a small time interval, divided by that interval.
Reference type: PR
Reference: I31-10, 10-35.a
Supplemental References: none

Quantity: volumetric entity emittance or capture rate (any elementary entity: atoms, molecules, ions, electrons, other particles, or specified groups of such particles)
Definition: The number of molecules or particles divided by volume, per time.
Reference type: PR
Reference: I31-10, 10-34.a
Supplemental References: none

EDCS Unit Label: INV_HENRY

EDCS Unit Symbolic Constant: EUC_INV_HENRY

EDCS Unit Code: 74

Symbol: 1/H

EDCS Unit Equivalence Class Label: RELUCTANCE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: reluctance
Definition: The magnetic potential difference divided by magnetic flux.
1/H = 1 A/Wb = 1 (s² · A²)/(m² · kg).
Reference type: PR
Reference: I31-5, 5-38.a
Supplemental References: none

EDCS Unit Label: INV_KELVIN

EDCS Unit Symbolic Constant: EUC_INV_KELVIN

EDCS Unit Code: 75

Symbol: 1/K

EDCS Unit Equivalence Class Label: LINEAR_EXPANSION_COEFF

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 3

Quantity: cubic expansion coefficient
Definition: The coefficient of volumic expansion divided by the thermodynamic temperature change.
Reference type: PR
Reference: I31-4, 4-3.a
Supplemental References: none

Quantity: linear expansion coefficient
Definition: The coefficient of linear expansion divided by the thermodynamic temperature change.
Reference type: PR
Reference: I31-4, 4-3.a
Supplemental References: none

Quantity: relative pressure coefficient
Definition: The coefficient of pressure change divided by the thermodynamic temperature change.
Reference type: PR
Reference: I31-4, 4-3.a
Supplemental References: none

EDCS Unit Label: INV_METRE

EDCS Unit Symbolic Constant: EUC_INV_METRE

EDCS Unit Code: 76

Symbol: 1/m

EDCS Unit Equivalence Class Label: INV_LENGTH

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 9

Quantity: angular reciprocal lattice vector
Definition: A vector whose scalar products with all fundamental lattice vectors are integral multiples of 2π.
Reference type: PR
Reference: I31-13, 13-2.a
Supplemental References: none

Quantity: angular repetency (angular wave number)
Definition: The reciprocal of the wavelength or the number of waves per unit angle along the direction of propagation.
Reference type: PR
Reference: I31-2, 2-7.b
Supplemental References: I31-6, 6-5.b; I31-7, 7-7.b; I31-13, 13-10.b

Quantity: curvature
Definition: The reciprocal of a radius of curvature.
Reference type: PR
Reference: I31-1, 1-4.a
Supplemental References: none

Quantity: fundamental reciprocal lattice vectors
Definition: The fundamental translation vectors for the reciprocal lattice.
Reference type: PR
Reference: I31-13, 13-2.a
Supplemental References: none

Quantity: linear attenuation coefficient (linear extinction coefficient)
Definition: The ratio of a quantity which is a function of distance divided by the distance between the measurements.
Reference type: PR
Reference: I31-6, 6-42.a
Supplemental References: I31-10, 10-13.a

Quantity: linear ionization by a particle
Definition: The number of elementary charges of the same sign produced over an element of length of the path of an ionizing charged particle, divided by that element.
Reference type: PR
Reference: I31-10, 10-23.a
Supplemental References: none

Quantity: repetency (wavenumber)
Definition: The reciprocal of the wavelength or the number of waves per unit length along the direction of propagation.
Reference type: PR
Reference: I31-2, 2-6.a
Supplemental References: I31-6, 6-4.a; I31-7, 7-6.a

Quantity: vergence (lens power)
Definition: The reciprocal of the distance between a point of reference and the point at which a pair of converging or diverging light rays intersect.
Reference type: PR
Reference: I31-6, 6-46.a
Supplemental References: none

Quantity: volumic cross-section (macroscopic cross-section)
Definition: Sum of the cross-sections for a reaction or process of a specified type over all atoms in a given volume, divided by that volume.
Reference type: PR
Reference: I31-10, 10-7.a
Supplemental References: none

EDCS Unit Label: INV_MICRON

EDCS Unit Symbolic Constant: EUC_INV_MICRON

EDCS Unit Code: 77

Symbol: 1/μm

EDCS Unit Equivalence Class Label: INV_LENGTH

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: angular repetency (angular wave number)
Definition: The reciprocal of the wavelength or the number of waves per unit angle along the direction of propagation.
1 μm^-1 = 10⁶ 1/m (exactly).
Reference type: PR
Reference: I31-2, 2-7.b
Supplemental References: I31-6, 6-5.b; I31-7, 7-7.b; I31-13, 13-10.b

Quantity: repetency (wavenumber)
Definition: The reciprocal of the wavelength or the number of waves per unit length along the direction of propagation.
Reference type: PR
Reference: I31-2, 2-6.a
Supplemental References: I31-6, 6-4.a; I31-7, 7-6.a

EDCS Unit Label: INV_MOLE

EDCS Unit Symbolic Constant: EUC_INV_MOLE

EDCS Unit Code: 78

Symbol: 1/mol

EDCS Unit Equivalence Class Label: MOLAR_DENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: molar density (Avogadro constant)
Definition: The number of molecules divided by the amount of substance.
Reference type: PR
Reference: I31-8, 8-4.a
Supplemental References: none

EDCS Unit Label: INV_PASCAL

EDCS Unit Symbolic Constant: EUC_INV_PASCAL

EDCS Unit Code: 79

Symbol: 1/Pa

EDCS Unit Equivalence Class Label: COMPRESSIBILITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 4

Quantity: bulk compressibility
Definition: The reciprocal of the bulk modulus.
Reference type: PR
Reference: I31-3, 3-19.a
Supplemental References: none

Quantity: compressibility
Definition: The extent to which a material reduces its volume when it is subjected to compressive stresses.
1/Pa = 1 (m · s²)/kg.
Reference type: PR
Reference: I31-3, 3-19.a
Supplemental References: none

Quantity: isentropic compressibility
Definition: At a constant value of entropy, the extent to which a material reduces its volume when it is subjected to compressive stresses.
Reference type: PR
Reference: I31-4, 4-5.a
Supplemental References: none

Quantity: isothermal compressibility
Definition: At a constant temperature, the extent to which a material reduces its volume when it is subjected to compressive stresses.
Reference type: PR
Reference: I31-4, 4-5.a
Supplemental References: none

EDCS Unit Label: INV_RADIAN

EDCS Unit Symbolic Constant: EUC_INV_RADIAN

EDCS Unit Code: 80

Symbol: 1/rad

EDCS Unit Equivalence Class Label: RECIPROCAL_PLANE_ANGLE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: reciprocal plane angle
Definition: The reciprocal of the angle between two half-lines terminating at the same point is the ratio of the radius of a circle (with its centre at that point) to the length of the included arc of that circle.
1 rad^-1 = 1 m/m = 1.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: INV_SEC_STERADIAN

EDCS Unit Symbolic Constant: EUC_INV_SEC_STERADIAN

EDCS Unit Code: 81

Symbol: 1/(s · sr)

EDCS Unit Equivalence Class Label: PHOTON_INTENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: photon intensity
Definition: In a given direction from a source, the photon flux leaving the source, or an element of the source, in an element of solid angle containing the given direction, divided by that element of solid angle.
Reference type: PR
Reference: I31-6, 6-24.a
Supplemental References: none

EDCS Unit Label: INV_SECOND

EDCS Unit Symbolic Constant: EUC_INV_SECOND

EDCS Unit Code: 82

Symbol: 1/s

EDCS Unit Equivalence Class Label: RATE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 7

Quantity: angular frequency
Definition: The frequency of rotation or vibration.
Reference type: PR
Reference: I31-2, 2-4.b
Supplemental References: I31-5, 5-42.b; I31-7, 7-4.b

Quantity: angular frequency
Definition: The number of cycles or revolutions divided by time.
Reference type: PR
Reference: I31-6, 6-2.b
Supplemental References: I31-9, 9-14.b; I31-9, 9-15.b; I31-13, 13-11.b

Quantity: damping coefficient
Definition: The factor defining the rate of exponential amplitude decay in a periodic or acoustic system.
Reference type: PR
Reference: I31-7, 7-23.a
Supplemental References: I31-2, 2-11.a

Quantity: decay constant (disintegration constant)
Definition: Probability of decay in a small time interval, divided by that interval.
Reference type: PR
Reference: I31-9, 9-36.a
Supplemental References: none

Quantity: photon flux
Definition: The number of photons in an incident beam of light received by a surface over a time interval.
Reference type: PR
Reference: I31-6, 6-23.a
Supplemental References: none

Quantity: pulsatance
Definition: The angular velocity of a periodic quantity.
Reference type: PR
Reference: I31-2, 2-4.b
Supplemental References: I31-5, 5-42.b; I31-7, 7-4.b

Quantity: rotational frequency
Definition: The number of revolutions divided by time.
Reference type: PR
Reference: I31-2, 2-3.b
Supplemental References: I31-5, 5-41.b

EDCS Unit Label: INV_SQ_CM_SEC_SR_EV

EDCS Unit Symbolic Constant: EUC_INV_SQ_CM_SEC_SR_EV

EDCS Unit Code: 83

Symbol: 1/(cm² · s · sr · eV)

EDCS Unit Equivalence Class Label: PARTICLE_FLUX_DENSITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: particle flux density within an energy range
Definition: At a point on a surface and in a given direction, the charged particle flux of an element of the surface within an energy range of 1 eV centered on a given particle energy, divided by the area of the orthogonal projection of this element on a plane perpendicular to the given direction, and divided by an element of solid angle containing the given direction.
1/(cm² · s · sr · eV) = 10^-6 1/(m² · s · sr · eV) (exactly).
Reference type: PR
Reference: I31-0, 2.3.2.3 (derived)
Supplemental References: none

EDCS Unit Label: INV_SQ_CM_SEC_SR_KEV

EDCS Unit Symbolic Constant: EUC_INV_SQ_CM_SEC_SR_KEV

EDCS Unit Code: 84

Symbol: 1/(cm² · s · sr · KeV)

EDCS Unit Equivalence Class Label: PARTICLE_FLUX_DENSITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: particle flux density within an energy range
Definition: At a point on a surface and in a given direction, the charged particle flux of an element of the surface within an energy range of 1 KeV centered on a given particle energy, divided by the area of the orthogonal projection of this element on a plane perpendicular to the given direction, and divided by an element of solid angle containing the given direction.
1/(cm² · s · sr · KeV) = 10^-9 1/(m² · s · sr · eV) (exactly, assuming an even distribution of particle energies).
Reference type: PR
Reference: I31-0, 2.3.2.3 (derived)
Supplemental References: none

EDCS Unit Label: INV_SQ_CM_SEC_SR_MEV

EDCS Unit Symbolic Constant: EUC_INV_SQ_CM_SEC_SR_MEV

EDCS Unit Code: 85

Symbol: 1/(cm² · s · sr · MeV)

EDCS Unit Equivalence Class Label: PARTICLE_FLUX_DENSITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: particle flux density within an energy range
Definition: At a point on a surface and in a given direction, the charged particle flux of an element of the surface within an energy range of 1 MeV centered on a given particle energy, divided by the area of the orthogonal projection of this element on a plane perpendicular to the given direction, and divided by an element of solid angle containing the given direction.
1/(cm² · s · sr · MeV) = 10^-12 1/(m² · s · sr · eV) (exactly, assuming an even distribution of particle energies).
Reference type: PR
Reference: I31-0, 2.3.2.3 (derived)
Supplemental References: none

EDCS Unit Label: INV_SQ_CM_SEC_STERADIAN

EDCS Unit Symbolic Constant: EUC_INV_SQ_CM_SEC_STERADIAN

EDCS Unit Code: 86

Symbol: 1/(cm² · s · sr)

EDCS Unit Equivalence Class Label: PHOTON_LUMINANCE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: photon luminance (photon radiance)
Definition: At a point on a surface and in a given direction, the photon intensity of an element of the surface, divided by the area of the orthogonal projection of this element on a plane perpendicular to the given direction.
1/(cm² · s · sr) = 10^-4 1/(m² · s · sr) (exactly).
Reference type: PR
Reference: I31-6, 6-25.a
Supplemental References: I31-0, 2.3.2.3

EDCS Unit Label: INV_SQ_M_SEC_SR_EV

EDCS Unit Symbolic Constant: EUC_INV_SQ_M_SEC_SR_EV

EDCS Unit Code: 87

Symbol: 1/(m² · s · sr · eV)

EDCS Unit Equivalence Class Label: PARTICLE_FLUX_DENSITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: particle flux density within an energy range
Definition: At a point on a surface and in a given direction, the charged particle flux of an element of the surface within an energy range of 1 eV centered on a given particle energy, divided by the area of the orthogonal projection of this element on a plane perpendicular to the given direction, and divided by an element of solid angle containing the given direction.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: INV_SQ_M_SEC_STERADIAN

EDCS Unit Symbolic Constant: EUC_INV_SQ_M_SEC_STERADIAN

EDCS Unit Code: 88

Symbol: 1/(m² · s · sr)

EDCS Unit Equivalence Class Label: PHOTON_LUMINANCE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: photon luminance (photon radiance)
Definition: At a point on a surface and in a given direction, the photon intensity of an element of the surface, divided by the area of the orthogonal projection of this element on a plane perpendicular to the given direction.
Reference type: PR
Reference: I31-6, 6-25.a
Supplemental References: none

EDCS Unit Label: INV_SQ_METRE

EDCS Unit Symbolic Constant: EUC_INV_SQ_METRE

EDCS Unit Code: 89

Symbol: 1/m²

EDCS Unit Equivalence Class Label: AREAL_ENTITY_DENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: areal entity density (any elementary entity: atoms, molecules, ions, electrons, other particles, or specified groups of such particles)
Definition: At a given point in space, the number of particles incident on a small sphere, divided by the cross-sectional area of that sphere.
Reference type: PR
Reference: I31-6, 6-28.a
Supplemental References: none

Quantity: particle fluence
Definition: At a given point in space, the number of particles incident on a small sphere, divided by the cross-sectional area of that sphere.
Reference type: PR
Reference: I31-10, 10-8.a
Supplemental References: none

EDCS Unit Label: INV_SQ_METRE_SEC

EDCS Unit Symbolic Constant: EUC_INV_SQ_METRE_SEC

EDCS Unit Code: 90

Symbol: 1/(m² · s)

EDCS Unit Equivalence Class Label: PARTICLE_CURRENT_DENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 4

Quantity: current density of particles
Definition: A vector quantity, the integral of whose normal component over any surface is equal to the net number of particles passing through that surface in a small time interval divided by that interval.
Reference type: PR
Reference: I31-10, 10-12.a
Supplemental References: none

Quantity: particle fluence rate (particle flux density)
Definition: At a given point in space, the number of particles incident on a small sphere in a small time interval, divided by the cross-sectional area of that sphere and by the time interval.
Reference type: PR
Reference: I31-10, 10-9.a
Supplemental References: I31-10, 10-31.a

Quantity: photon exitance
Definition: At a point on a surface, the photon flux leaving an element of the surface, divided by the area of that element and by the time interval.
Reference type: PR
Reference: I31-6, 6-26.a
Supplemental References: none

Quantity: photon irradiance
Definition: At a point on a surface, the photon flux incident on an element of the surface, divided by the area of that element and by the time interval.
Reference type: PR
Reference: I31-6, 6-27.a
Supplemental References: none

EDCS Unit Label: INV_STERADIAN

EDCS Unit Symbolic Constant: EUC_INV_STERADIAN

EDCS Unit Code: 91

Symbol: 1/sr

EDCS Unit Equivalence Class Label: RECIPROCAL_SOLID_ANGLE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: reciprocal solid angle
Definition: The reciprocal of a solid angle of a cone is the ratio of the square of the radius of a sphere (with its centre at the apex of that cone) to the area cut out on a spherical surface.
1 sr^-1 = 1 m²/m² = 1.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: INV_STERADIAN_METRE

EDCS Unit Symbolic Constant: EUC_INV_STERADIAN_METRE

EDCS Unit Code: 92

Symbol: 1/(sr · m)

EDCS Unit Equivalence Class Label: SPECTRAL_RECIPROCAL_SOLID_ANGLE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: spectral reciprocal solid angle
Definition: The reciprocal of a solid angle of a cone is the ratio of the square of the radius of a sphere (with its centre at the apex of that cone) to the area cut out on a spherical surface, as a function of radiant wavelength.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: INV_STERADIAN_MICRON

EDCS Unit Symbolic Constant: EUC_INV_STERADIAN_MICRON

EDCS Unit Code: 93

Symbol: 1/(sr · μm)

EDCS Unit Equivalence Class Label: SPECTRAL_RECIPROCAL_SOLID_ANGLE

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: spectral reciprocal solid angle
Definition: The reciprocal of a solid angle of a cone is the ratio of the square of the radius of a sphere (with its centre at the apex of that cone) to the area cut out on a spherical surface, as a function of radiant wavelength.
1/(sr · μm) = 10⁶ 1/(sr · m) (exactly).
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: JANSKY

EDCS Unit Symbolic Constant: EUC_JANSKY

EDCS Unit Code: 94

Symbol: Jy

EDCS Unit Equivalence Class Label: FLUX_DENSITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: flux density
Definition: The amount of a given type of radiation that crosses a specified area within a specified period.
1 Jy = 10^-26 W/(m² · Hz) (exactly).
Reference type: PR
Reference: I31-0, 2.3.1
Supplemental References: none

EDCS Unit Label: JOULE

EDCS Unit Symbolic Constant: EUC_JOULE

EDCS Unit Code: 95

Symbol: J

EDCS Unit Equivalence Class Label: ENERGY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 18

Quantity: alpha disintegration energy
Definition: The sum of the kinetic energy of the alpha particle produced in the disintegration process and the recoil energy of the product atom in the reference frame in which the emitting nucleus is at rest before its disintegration.
Reference type: PR
Reference: I31-9, 9-38.a
Supplemental References: none

Quantity: average energy loss per ion pair formed (average energy loss per elementary charge of the same sign produced)
Definition: The initial kinetic energy of an ionizing charged particle, divided by the total ionization produced by that particle.
Reference type: PR
Reference: I31-10, 10-25.a
Supplemental References: none

Quantity: beta disintegration energy
Definition: Sum of the maximum beta particle energy and the recoil energy of the atom produced in the reference frame in which the emitting nucleus is at rest before its disintegration.
Reference type: PR
Reference: I31-9, 9-40.a
Supplemental References: none

Quantity: electron affinity
Definition: The energy difference between an electron at rest at infinity and an electron at the lowest level of the conduction band in an insulator or semiconductor.
Reference type: PR
Reference: I31-13, 13-26.a
Supplemental References: none

Quantity: energy
Definition: The amount of work.
1 J = 1 N·m = 1 (m² · kg)/s².
Reference type: PR
Reference: I31-0, Table 2
Supplemental References: I31-3, 3-26.a

Quantity: energy imparted
Definition: The energy imparted by ionizing radiation to the matter in a given volume is the difference between the sum of the energies of all the directly ionizing (charged) and indirectly ionizing (uncharged) particles which have entered the volume and the sum of the energies of all those which have left it, minus the energy equivalent of any increase in rest mass that has taken place in nuclear or elementary particle reactions within the volume.
Reference type: PR
Reference: I31-10, 10-50.a
Supplemental References: none

Quantity: enthalpy
Definition: Heat content.
Reference type: PR
Reference: I31-4, 4-20.a
Supplemental References: none

Quantity: exchange integral
Definition: The interaction energy arising from electron exchange.
Reference type: PR
Reference: I31-13, 13-35.a
Supplemental References: none

Quantity: Fermi energy
Definition: In a metal, the highest energy of occupied states at zero thermodynamic temperature.
Reference type: PR
Reference: I31-13, 13-28.a
Supplemental References: none

Quantity: gap energy
Definition: Difference in energy between lowest level of conduction band and highest level of valence band.
Reference type: PR
Reference: I31-13, 13-28.b
Supplemental References: none

Quantity: heat (quantity of heat)
Definition: Energy that is the result of the temperature difference between the boundary of a system and its surrounding environment.
Reference type: PR
Reference: I31-4, 4-6.a
Supplemental References: none

Quantity: level width
Definition: The uncertainty in energy (full width at half maximum) of an unstable state due to the finite lifetime of the state.
Reference type: PR
Reference: I31-9, 9-32.a
Supplemental References: none

Quantity: maximum beta particle energy
Definition: Maximum energy of the energy spectrum in a beta disintegration process.
Reference type: PR
Reference: I31-9, 9-39.a
Supplemental References: none

Quantity: mean energy imparted
Definition: The expectation value of the energy imparted.
Reference type: PR
Reference: I31-10, 10-50.a
Supplemental References: none

Quantity: radiant energy
Definition: The energy emitted, transferred or received as radiation.
Reference type: PR
Reference: I31-6, 6-7.a
Supplemental References: none

Quantity: reaction energy
Definition: In a nuclear reaction, the sum of the kinetic and photon energies of the reaction products minus the sum of the kinetic and photon energies of the reactants.
Reference type: PR
Reference: I31-10, 10-1.a
Supplemental References: none

Quantity: resonance energy
Definition: Kinetic energy of an incident particle, in the reference frame of the target, corresponding to a resonance in a nuclear reaction.
Reference type: PR
Reference: I31-10, 10-2.a
Supplemental References: none

Quantity: work function
Definition: The energy difference between an electron at rest at infinity and an electron at the Fermi level in the interior of a substance.
Reference type: PR
Reference: I31-13, 13-25.a
Supplemental References: none

EDCS Unit Label: JOULE_METRE_SQD

EDCS Unit Symbolic Constant: EUC_JOULE_METRE_SQD

EDCS Unit Code: 96

Symbol: J · m²

EDCS Unit Equivalence Class Label: TOTAL_ATOMIC_STOPPING_POWER

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: total atomic stopping power
Definition: The total linear stopping power divided by the number density of the atoms in the substance.
1 J · m² = 1 (m⁴ · kg)/s².
Reference type: PR
Reference: I31-10, 10-19.a
Supplemental References: none

EDCS Unit Label: JOULE_METRE_SQD_PER_KG

EDCS Unit Symbolic Constant: EUC_JOULE_METRE_SQD_PER_KG

EDCS Unit Code: 97

Symbol: (J · m²)/kg

EDCS Unit Equivalence Class Label: TOTAL_MASS_STOPPING_POWER

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: total mass stopping power
Definition: The total linear stopping power divided by the volumic mass of the substance.
1 (J · m²)/kg = 1 m⁴/s².
Reference type: PR
Reference: I31-10, 10-20.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_CUBIC_M

EDCS Unit Symbolic Constant: EUC_JOULE_PER_CUBIC_M

EDCS Unit Code: 98

Symbol: J/m³

EDCS Unit Equivalence Class Label: ENERGY_DENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 3

Quantity: radiant energy density
Definition: The radiant energy in an element of volume, divided by that element.
Reference type: PR
Reference: I31-6, 6-8.a
Supplemental References: none

Quantity: sound energy density (volumic sound energy)
Definition: The mean sound energy in a given volume divided by that volume.
Reference type: PR
Reference: I31-7, 7-15.a
Supplemental References: none

Quantity: volumic electromagnetic energy (electromagnetic energy density)
Definition: The energy in an element of volume, divided by that element.
1 J/m³ = 1 kg/(m · s²).
Reference type: PR
Reference: I31-5, 5-30.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_GRAM_K

EDCS Unit Symbolic Constant: EUC_JOULE_PER_GRAM_K

EDCS Unit Code: 99

Symbol: J/(g · K)

EDCS Unit Equivalence Class Label: SPECIFIC_HEAT_CAPACITY

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: massic entropy (specific entropy)
Definition: The heat entropy divided by mass.
Reference type: PR
Reference: I31-4, 4-19.a
Supplemental References: none

Quantity: massic heat capacity (specific heat capacity)
Definition: The heat capacity divided by mass.
1 J/(g · K) = 10³ J/(kg · K) (exactly).
Reference type: PR
Reference: I31-4, 4-16.a
Supplemental References: I31-0, 2.3.2.3

EDCS Unit Label: JOULE_PER_KELVIN

EDCS Unit Symbolic Constant: EUC_JOULE_PER_KELVIN

EDCS Unit Code: 100

Symbol: J/K

EDCS Unit Equivalence Class Label: HEAT_CAPACITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 3

Quantity: Boltzmann constant
Definition: A constant equal to 1,38 x 10^-23 J/K, used in statistical physics.
Reference type: PR
Reference: I31-8, 8-37.a
Supplemental References: none

Quantity: entropy
Definition: When a small quantity of heat dQ is received by a system the thermodynamic temperature of which is T, the entropy of the system is increased by dQ/T, provided that no irreversible change takes place in the system.
Reference type: PR
Reference: I31-4, 4-18.a
Supplemental References: none

Quantity: heat capacity
Definition: The quantity dQ/dT, when the temperature of a system is increased by dT as a result of the addition of a small quantity of heat dQ.
1 J/K = 1 (m² · kg)/(s² · K).
Reference type: PR
Reference: I31-4, 4-15.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_KELVIN_MOLE

EDCS Unit Symbolic Constant: EUC_JOULE_PER_KELVIN_MOLE

EDCS Unit Code: 101

Symbol: J/(K · mol)

EDCS Unit Equivalence Class Label: MOLAR_ENTROPY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 3

Quantity: molar entropy
Definition: The heat entropy divided by the amount of substance.
Reference type: PR
Reference: I31-8, 8-9.a
Supplemental References: none

Quantity: molar gas constant
Definition: The universal constant of proportionality in the ideal gas law: pV_m = RT.
Reference type: PR
Reference: I31-8, 8-36.a
Supplemental References: none

Quantity: molar heat capacity
Definition: The heat capacity divided by the amount of substance.
1 J/(K · mol) = 1 (m² · kg)/(s² · K · mol).
Reference type: PR
Reference: I31-8, 8-8.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_KG

EDCS Unit Symbolic Constant: EUC_JOULE_PER_KG

EDCS Unit Code: 102

Symbol: J/kg

EDCS Unit Equivalence Class Label: SPECIFIC_ENERGY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: specific energy
Definition: The energy divided by mass.
1 J/kg = 1 m²/s².
Reference type: PR
Reference: I31-4, 4-21.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_KG_KELVIN

EDCS Unit Symbolic Constant: EUC_JOULE_PER_KG_KELVIN

EDCS Unit Code: 103

Symbol: J/(kg · K)

EDCS Unit Equivalence Class Label: SPECIFIC_HEAT_CAPACITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: massic entropy (specific entropy)
Definition: The heat entropy divided by mass.
Reference type: PR
Reference: I31-4, 4-19.a
Supplemental References: none

Quantity: massic heat capacity (specific heat capacity)
Definition: The heat capacity divided by mass.
1 J/(kg · K) = 1 m²/(s² · K).
Reference type: PR
Reference: I31-4, 4-16.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_KM

EDCS Unit Symbolic Constant: EUC_JOULE_PER_KM

EDCS Unit Code: 104

Symbol: J/km

EDCS Unit Equivalence Class Label: LINEAR_ENERGY_TRANSFER

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: linear energy transfer
Definition: For an ionizing charged particle, the energy imparted locally to matter in traversing a small distance through the matter, divided by that distance.
1 J/km = 10^-3 J/m (exactly).
Reference type: PR
Reference: I31-10, 10-54.a
Supplemental References: none

Quantity: total linear stopping power
Definition: For an ionizing charged particle, the energy imparted locally to matter in traversing a small distance through the matter, divided by that distance; -dE/dx.
1 J/km = 1 x 10^-3 J/m (exactly).
Reference type: PR
Reference: I31-10, 10-18.a
Supplemental References: I31-0, 2.3.2.3

EDCS Unit Label: JOULE_PER_M_FOURTH_PWR

EDCS Unit Symbolic Constant: EUC_JOULE_PER_M_FOURTH_PWR

EDCS Unit Code: 105

Symbol: J/m⁴

EDCS Unit Equivalence Class Label: SPECTRAL_RAD_ENERGY_DENSITY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: spectral concentration of radiant energy density (in terms of wavelength)
Definition: The radiant energy density in an infinitesimal wavelength interval, divided by the range of that interval.
1 J/m⁴ = 1 kg/(m² · s²).
Reference type: PR
Reference: I31-6, 6-9.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_METRE

EDCS Unit Symbolic Constant: EUC_JOULE_PER_METRE

EDCS Unit Code: 106

Symbol: J/m

EDCS Unit Equivalence Class Label: LINEAR_ENERGY_TRANSFER

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: linear energy transfer
Definition: For an ionizing charged particle, the energy imparted locally to matter in traversing a small distance through the matter, divided by that distance.
1 J/m = 1 (m · kg)/s².
Reference type: PR
Reference: I31-10, 10-54.a
Supplemental References: none

Quantity: total linear stopping power
Definition: For an ionizing charged particle, the energy imparted locally to matter in traversing a small distance through the matter, divided by that distance; -dE/dx.
Reference type: PR
Reference: I31-10, 10-18.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_MOLE

EDCS Unit Symbolic Constant: EUC_JOULE_PER_MOLE

EDCS Unit Code: 107

Symbol: J/mol

EDCS Unit Equivalence Class Label: MOLAR_ENERGY

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: chemical potential
Definition: A partial molar Gibbs free energy; the change in Gibbs free energy when one mole of a substance is added to a very large amount of a sample.
Reference type: PR
Reference: I31-8, 8-17.a
Supplemental References: none

Quantity: molar thermodynamic energy
Definition: The thermodynamic energy divided by the amount of substance.
1 J/mol = 1 (m² · kg)/(s² · mol).
Reference type: PR
Reference: I31-8, 8-7.a
Supplemental References: none

EDCS Unit Label: JOULE_PER_SQ_METRE

EDCS Unit Symbolic Constant: EUC_JOULE_PER_SQ_METRE

EDCS Unit Code: 108

Symbol: J/m²

EDCS Unit Equivalence Class Label: RADIANT_ENERGY_FLUENCE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: energy fluence
Definition: At a given point in space, the sum of the energies, exclusive of rest energy, of all the particles incident on a small sphere, divided by the cross-sectional area of that sphere.
Reference type: PR
Reference: I31-10, 10-10.a
Supplemental References: none

Quantity: radiant energy fluence
Definition: At a given point in space, the radiant flux incident on a small sphere, divided by the cross-sectional area of that sphere.
1 J/m² = 1 kg/s².
Reference type: PR
Reference: I31-6, 6-11.a
Supplemental References: none

EDCS Unit Label: JOULE_SECOND

EDCS Unit Symbolic Constant: EUC_JOULE_SECOND

EDCS Unit Code: 109

Symbol: J · s

EDCS Unit Equivalence Class Label: PLANCK_CONSTANT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: Planck constant
Definition: 1 J · s = 1 (m² · kg)/s.
Reference type: PR
Reference: I31-9, 9-7.a
Supplemental References: none

EDCS Unit Label: KELVIN

EDCS Unit Symbolic Constant: EUC_KELVIN

EDCS Unit Code: 110

Symbol: K

EDCS Unit Equivalence Class Label: THERMO_TEMPERATURE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: thermodynamic temperature
Definition: The fraction 1 / 273,16 of the thermodynamic temperature of the triple point of water.
SI base unit.
Reference type: PR
Reference: I31-0, Table 1
Supplemental References: I31-4, 4-1.a; I31-13, 13-12.a; I31-13, 13-29.a; I31-13, 13-36.a

EDCS Unit Label: KELVIN_PER_KM

EDCS Unit Symbolic Constant: EUC_KELVIN_PER_KM

EDCS Unit Code: 111

Symbol: K/km

EDCS Unit Equivalence Class Label: LINEIC_THERMO_TEMP_GRADIENT

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 1

Quantity: lineic thermodynamic temperature gradient
Definition: The thermodynamic temperature difference divided by distance.
1 K/km = 10^-3 K/m (exactly).
Reference type: PR
Reference: I31-0, 2.3.2.2 and 2.3.2.3 (derived)
Supplemental References: none

EDCS Unit Label: KELVIN_PER_METRE

EDCS Unit Symbolic Constant: EUC_KELVIN_PER_METRE

EDCS Unit Code: 112

Symbol: K/m

EDCS Unit Equivalence Class Label: LINEIC_THERMO_TEMP_GRADIENT

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: lineic thermodynamic temperature gradient
Definition: The thermodynamic temperature difference divided by distance.
Reference type: PR
Reference: I31-0, 2.3.2.2 (derived)
Supplemental References: none

EDCS Unit Label: KELVIN_PER_SEC

EDCS Unit Symbolic Constant: EUC_KELVIN_PER_SEC

EDCS Unit Code: 113

Symbol: K/s

EDCS Unit Equivalence Class Label: THERMO_TEMP_CHANGE_RATE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: thermodynamic temperature change rate
Definition: The thermodynamic temperature change over an interval of time, divided by that time.
Reference type: PR
Reference: I31-0, 2.3.2.2 and 2.3.4 (derived)
Supplemental References: none

EDCS Unit Label: KELVIN_PER_WATT

EDCS Unit Symbolic Constant: EUC_KELVIN_PER_WATT

EDCS Unit Code: 114

Symbol: K/W

EDCS Unit Equivalence Class Label: THERMAL_RESISTANCE

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: thermal resistance
Definition: The temperature difference divided by heat flow rate.
1 K/W = 1 (m² · kg · K)/s³.
Reference type: PR
Reference: I31-4, 4-12.a
Supplemental References: none

EDCS Unit Label: KG_METRE_PER_SEC

EDCS Unit Symbolic Constant: EUC_KG_METRE_PER_SEC

EDCS Unit Code: 115

Symbol: kg · m/s

EDCS Unit Equivalence Class Label: MOMENTUM

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: momentum
Definition: The product of mass and velocity.
Reference type: PR
Reference: I31-3, 3-8.a
Supplemental References: none

EDCS Unit Label: KG_METRE_SQD

EDCS Unit Symbolic Constant: EUC_KG_METRE_SQD

EDCS Unit Code: 116

Symbol: kg · m²

EDCS Unit Equivalence Class Label: MOMENT_INERTIA

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: moment of inertia (about an axis)
Definition: The sum (integral) of the products of the elements of mass of a body and the squares of their distances from an axis.
Reference type: PR
Reference: I31-3, 3-7.a
Supplemental References: none

EDCS Unit Label: KG_METRE_SQD_PER_SEC

EDCS Unit Symbolic Constant: EUC_KG_METRE_SQD_PER_SEC

EDCS Unit Code: 117

Symbol: (kg · m²)/s

EDCS Unit Equivalence Class Label: ANGULAR_MOMENTUM

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: moment of momentum (angular momentum)
Definition: The moment of momentum of a particle about a point is equal to the vector product of the radius vector from this point to the particle and the momentum of the particle.
Reference type: PR
Reference: I31-3, 3-11.a
Supplemental References: none

EDCS Unit Label: KG_PER_CUBIC_METRE

EDCS Unit Symbolic Constant: EUC_KG_PER_CUBIC_METRE

EDCS Unit Code: 118

Symbol: kg/m³

EDCS Unit Equivalence Class Label: VOLUMIC_MASS

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 2

Quantity: mass concentration (of B)
Definition: The amount of substance of B divided by the volume of the mixture.
Reference type: PR
Reference: I31-8, 8-11.a
Supplemental References: none

Quantity: volumic mass (mass density)
Definition: The mass divided by the volume.
Reference type: PR
Reference: I31-3, 3-2.a
Supplemental References: I31-7, 7-8.a

EDCS Unit Label: KG_PER_KG

EDCS Unit Symbolic Constant: EUC_KG_PER_KG

EDCS Unit Code: 119

Symbol: kg/kg

EDCS Unit Equivalence Class Label: MASS_FRACTION

Unit Status: Recommended

Number of quantities which this unit of measure may represent:: 1

Quantity: mass fraction (of B)
Definition: The mass of B divided by the mass of the mixture.
1 kg/kg = 1.
Reference type: PR
Reference: I31-8, 8-12.a
Supplemental References: I31-0, 2.3.3

EDCS Unit Label: KG_PER_LITRE

EDCS Unit Symbolic Constant: EUC_KG_PER_LITRE

EDCS Unit Code: 120

Symbol: kg/l

EDCS Unit Equivalence Class Label: VOLUMIC_MASS

Unit Status: Accepted

Number of quantities which this unit of measure may represent:: 2

Quantity: mass concentration (of B)
Definition: The amount of substance of B divided by the volume of the mixture.
Reference type: PR
Reference: I31-8, 8-11.b
Supplemental References: none

Contents

EDCS Unit Dictionary