Health informatics - Expression of results of measurements in health sciences

This document is intended for use by parties to the design, development, acquisition, use and monitoring of health-care related information and information systems. It provides a list of units of measurement to be used in representing values of measurable quantities in health sciences.
The International System of Units forms the basis for this EN. Units with their associated kinds-of-quantity are arranged in order of dimension in Tables 1, 2 and 4 (Clause 5), and in Annex A.
Different kinds-of-quantity may apply to a given combination of component(s) and system. Often the different quantities are interconvertible and examples of such interconvertibility are given in Annex C.
Tables of conversion factors (Annex A) are provided from units in current use to SI units or their multiples.
To represent the result of a measurement (Clause 6), this EN addresses requirements for the following:
3   relational operator (Clause 4)
3   numerical value (Subclause 6.1)
3   uncertainty of measurement (Subclause 6.2; Annex D)
3   unit of measurement (Clause 5).
This EN covers the requirements for representation of these data elements in displayed and printed form, and provides an approach for support of languages in non-Roman alphabets (Clause 7).
The scope of this standard is limited to textual representation. Support is not provided for the display or printing of images or graphs.
This standard does not cover the requirements for expression of the results of measurements in speech, speech synthesis or handwriting. It does not cover the form and syntax of requests for clinical measurements, nor detailed aspects of data transmission. It refers the user to other CEN standards that address the detailed specification of the interchange format. It does not address the syntax for recording of natural-language statements about quantities, such as those used in recording information about drugs dispensed or about treatment of patients. It does not cover the units of financial quantitie

Medizinische Informatik - Darstellung der Ergebnisse von Messungen in den Gesundheitswissenschaften

Informatique de santé - Expression des résultats de mesure dans le domaine de la santé

Zdravstvena informatika – Prikaz rezultatov meritev v medicinskih znanostih

General Information

Status
Published
Publication Date
31-Mar-2006
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Apr-2006
Due Date
01-Apr-2006
Completion Date
01-Apr-2006

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SLOVENSKI STANDARD
SIST EN 12435:2006
01-april-2006
1DGRPHãþD
SIST ENV 12435:2003
Zdravstvena informatika – Prikaz rezultatov meritev v medicinskih znanostih
Health informatics - Expression of results of measurements in health sciences
Medizinische Informatik - Darstellung der Ergebnisse von Messungen in den
Gesundheitswissenschaften

Informatique de santé - Expression des résultats de mesure dans le domaine de la santé

Ta slovenski standard je istoveten z: EN 12435:2006
ICS:
35.240.80 Uporabniške rešitve IT v IT applications in health care
zdravstveni tehniki technology
SIST EN 12435:2006 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 12435:2006
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SIST EN 12435:2006
EUROPEAN STANDARD
EN 12435
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2006
ICS 11.020; 35.240.70 Supersedes ENV 12435:1999
English Version
Health informatics - Expression of results of measurements in
health sciences

Informatique de santé - Expression des résultats de Medizinische Informatik - Darstellung der Ergebnisse von

mesure dans le domaine de la santé Messungen in den Gesundhetswissenschaften
This European Standard was approved by CEN on 14 December 2005.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European

Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national

standards may be obtained on application to the Central Secretariat or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official

versions.

CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,

Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,

Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels

© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12435:2006: E

worldwide for CEN national Members.
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SIST EN 12435:2006
EN 12435:2006 (E)
Contents

Foreword.................................................................................................................................................................. 3

Introduction ............................................................................................................................................................. 4

1 Scope........................................................................................................................................................... 5

2 Normative references................................................................................................................................. 5

3 Definitions, abbreviations and acronyms................................................................................................. 6

3.1 Definitions................................................................................................................................................... 6

3.2 Abbreviations, initialisms and acronyms ................................................................................................. 9

4 Elements of data in a measurable quantity and its result ..................................................................... 10

5 Units for reporting information in health sciences ................................................................................ 11

5.2 Derived coherent units of SI and mathematical operations with units................................................. 12

5.3 Derived coherent units of SI with special names and symbols ............................................................ 13

5.4 Multiples and submultiples of units: prefix names and symbols ......................................................... 13

5.5 Units outside SI: off-system units........................................................................................................... 17

5.6 Units of dimensionless quantities and compound units with the unit `one' in the

numerator.................................................................................................................................................. 19

6 Expression of numerical value and uncertainty..................................................................................... 21

6.1 Numerical values...................................................................................................................................... 21

6.1 Numerical values...................................................................................................................................... 21

6.2 Uncertainty of measurement................................................................................................................... 22

7 Representation of the results of measurement...................................................................................... 22

7.1 Display and printing ................................................................................................................................. 22

7.2 Transmission and storage ....................................................................................................................... 23

8 Deprecation of the use of "limited" (e.g. 7-bit) character sets.............................................................. 24

Annex A (informative) Table of kinds-of-quantity, their units and conversion factors

(informative).............................................................................................................................................. 25

Annex B (informative) Dimension of a quantity............................................................................................... 103

Annex C (informative) Conversion between kinds-of-quantity....................................................................... 104

Annex D (normative) Uncertainty of measurement ......................................................................................... 107

Annex E (normative) Rounding numerical values ........................................................................................... 109

Annex F (informative) Non-measurable properties ......................................................................................... 113

Bibliography ........................................................................................................................................................ 114

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SIST EN 12435:2006
EN 12435:2006 (E)
Foreword

This document (EN 12435:2006) has been prepared by Technical Committee CEN/ TC 251 "Health

informatics", the secretariat of which is held by NEN.

This document falls under mandate BC/CEN/03/ 255/97/23 of the European Commission and the

European Free Trade Association.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by July 2006, and conflicting national standards shall be

withdrawn at the latest by July 2006.
This document supersedes ENV 12435:1999.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech

Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,

Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia,

Slovenia, Spain, Sweden, Switzerland and United Kingdom.
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SIST EN 12435:2006
EN 12435:2006 (E)
Introduction

Results of measurements on the human or animal body, and its environment are essential in the

health sciences. The disciplines involved in measurement often use different ways of expressing their

results. Conventions within user groups are not universally applicable. The situation is further

complicated by differences in the ways they are expressed in national legislation and in local

administration. From the many available conventions, a consensus must therefore be reached on how

to express the results of measurements on the body and its environment, particularly for exchange

between information systems.

Universal principles for the expression of measurements have been laid down by Technical

Committee 12 of the International Organization for Standardization in its series of standards ISO 31

and ISO 1000, which implement the International System of Units (SI) defined by the General

Conference on Weights and Measures. Those principles have been applied to biological systems and

certain units have been added by the International Council on Radiological Protection, International

Council on Standardization in Haematology, the International Federation of Clinical Chemistry, the

International Union of Biochemistry and Molecular Biology, the International Union of Pure and

Applied Chemistry and the World Health Organization. Implementation of this EN will provide wider

comprehension and interaction between countries and specialities.

The main normative provisions of this European standard are expressed in Clauses 5, 6 and 7. They

include the following aspects of the performance of a device or system related to the result of a

measurement:

 the selection of kind-of-quantity and the unit in which to express it in accordance with the

provisions of Clause 5

 where reported, the uncertainty of the value in accordance with the provisions of Annex D

 for the purposes of display, printing, transmission and storage, the elements of the results of

measurement in accordance with the provisions of Clause 7.
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SIST EN 12435:2006
EN 12435:2006 (E)
1 Scope

This document is intended for use by parties to the design, development, acquisition, use and monitoring

of health-care related information and information systems. It provides a list of units of measurement to

be used in representing values of measurable quantities in health sciences.

The International System of Units forms the basis for this EN. Units with their associated kinds-of-quantity

are arranged in order of dimension in Tables 1, 2 and 4 (Clause 5), and in Annex A.

Different kinds-of-quantity may apply to a given combination of component(s) and system. Often the

different quantities are interconvertible and examples of such interconvertibility are given in Annex C.

Tables of conversion factors (Annex A) are provided from units in current use to SI units or their multiples.

To represent the result of a measurement (Clause 6), this EN addresses requirements for the following:

 relational operator (Clause 4)
 numerical value (Subclause 6.1)
 uncertainty of measurement (Subclause 6.2; Annex D)
 unit of measurement (Clause 5).

This EN covers the requirements for representation of these data elements in displayed and printed form,

and provides an approach for support of languages in non-Roman alphabets (Clause 7).

The scope of this standard is limited to textual representation. Support is not provided for the display or

printing of images or graphs.

This standard does not cover the requirements for expression of the results of measurements in speech,

speech synthesis or handwriting. It does not cover the form and syntax of requests for clinical

measurements, nor detailed aspects of data transmission. It refers the user to other CEN standards that

address the detailed specification of the interchange format. It does not address the syntax for recording

of natural-language statements about quantities, such as those used in recording information about drugs

dispensed or about treatment of patients. It does not cover the units of financial quantities, which are

covered by ISO 4217.
2 Normative references

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

document (including any amendments) applies.

ISO 31-11:1992, Quantities and units – Part 11: Mathematical signs and symbols for use in the

physical sciences and technology.
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SIST EN 12435:2006
EN 12435:2006 (E)
3 Definitions, abbreviations and acronyms
3.1 Definitions
3.1.1
base kind-of-quantity

one of the kinds-of-quantity that, in a system of kinds-of-quantity, are conventionally accepted as

functionally independent of one another (after VIM)
3.1.2
base unit

unit of measurement of a base kind-of-quantity in a given system of kinds-of-quantity (after VIM)

3.1.3
character

member of a set of elements used for the organization, control or representation of information (after

ISO 10 646-1)
3.1.4
coded character
character in its coded representation (after ISO 10 646-1)
3.1.5
coherent unit

derived unit of measurement that may be expressed as a product of powers of base units with the

proportionality factor one (VIM)
3.1.6
component
definable part of a system (ENV 1614)

NOTE In analytical chemistry, component is sometimes called constituent or analyte.

3.1.7
derived kind-of-quantity

kind-of-quantity defined, in a system of kinds-of-quantity, as a function of base kinds-of-quantity of

that system (after VIM)
3.1.8
derived unit

unit of measurement of a derived kind-of-quantity in a given system of kinds-of-quantity (after VIM)

3.1.9
dimension of quantity

expression that represents a quantity in a system of quantities as the product of powers of factors that

represent the base kinds-of-quantity of the system (after VIM)
NOTE The use of this term is explained in Annex B.
3.1.10
entity
that which can be individually described and considered
[ISO 8402:1994]
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SIST EN 12435:2006
EN 12435:2006 (E)

NOTE 1 The word unit is used for this concept in statistics and in counting for what is counted, which may be,

for instance, physical objects, physical particles, repetitive operations or repetitive processes, or any combination

of such (detected, for instance, by pattern recognition).

NOTE 2 The concept is called element in set theory, in which a collection of elements constitute a set:

element - set
In this context, a component may be considered as a set of entities:
entity - component

NOTE 3 An entity, in contrast to a unit of measurement, constitutes part of the specification of a component

(on the left side of the equation in Subclause 4.2) and not part of the unit of measurement (on the right side of the

equation). The entity thus forms part of the specification of the measurable quantity. Some examples of such

measurable quantities based on counting are given in Subclause 5.6.5.
3.1.11
factor prefix

prefix word or symbol for attachment to the name or symbol of a unit in order to form units that are

multiples or submultiples of that unit

NOTE Factor prefixes provide a series to allow submultiples and multiples of SI units in the range 10-24 to

1024.
3.1.12
graphic character
character in its visible representation
[ISO 10 646-1]
3.1.13
interchange

transfer of character-coded data from one user to another, using telecommunication means or

interchangeable carriers (after ISO 10 646-1)
3.1.14
International System of Units (SI)

coherent system of units adopted and recommended by the General Conference on Weights and

Measures (VIM)
3.1.15
kind-of-quantity

element of information common to a set of mutually comparable measurable quantities and necessary

for the definition of a measurable quantity, along with a system and often a component

NOTE 1 The definition of this concept is under discussion in ISO/TC12.

NOTE 2 The unqualified word quantity is also widely used for this concept, which VIM calls quantity in a

general sense.

NOTE 3 A kind-of-quantity can be designated by a name or a symbol, but cannot be measured.

EXAMPLES:
 pressure p
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SIST EN 12435:2006
EN 12435:2006 (E)
 substance concentration c
 length l
3.1.16
measurable quantity

attribute of a phenomenon, body or substance that may be distinguished qualitatively and determined

quantitatively (VIM)

NOTE 1 Phenomenon, body or substance correspond to the concepts of system and component as used in

clinical laboratory sciences. Qualitatively refers to the need to define a quantity before it can be measured.

NOTE 2 A measurable quantity is defined by several elements of information, here called kind-of-quantity,

component and system.
EXAMPLES:

 pressure (kind-of-quantity) of air (component) in surgical theatre of hospital X at 1995-05-01

10:00 (system)

 substance concentration (kind-of-quantity) of dioxygen (component) in blood of John Smith (born

at place X on 1950-01-1) at time 1995-05-01 10:00 (system)

 length (kind-of-quantity) of John Smith (born at place X on 1950-01-1) at time 1995-05-01 10:00

(system)
3.1.17
measurement
set of operations having the object of determining a value of a quantity (VIM)
3.1.18
numerical value

quotient of the value of a quantity and the unit used in its expression (after VIM)

3.1.19
octet
ordered sequence of eight bits considered as an entity (after ISO 10 646-1)
3.1.20
off-system unit
unit of measurement that does not belong to a given system of units (VIM)
3.1.21
quantity
see kind-of-quantity and measurable quantity.
3.1.22
result of measurement
value attributed to a measurable quantity obtained by measurement (after VIM)

NOTE For the purposes of this ENV, result is taken to include the relational operator (Subclauses 4.1 and

4.3) and a measurable value of uncertainty (Annex D).
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SIST EN 12435:2006
EN 12435:2006 (E)
3.1.23
scale

set of possible values that may be attributed to a quantity of a certain kind (after ENV 1614)

NOTE In instrumentation, scale also means the ordered set of marks … forming part of the display on a

measuring instrument (VIM).
3.1.24
symbol

representation of a concept by letters, numerals, pictograms or any combination thereof (after ISO

1087:1990)
3.1.25
system

demarcated arrangement of a set of elements and a set of relationships between these elements

(ENV 1614)
3.1.26
systematic name
name consistent with the principles of a nomenclature (ENV 1614)
3.1.27
uncertainty of measurement

parameter that is associated with the result of a measurement and that characterizes the dispersion of

the values attributable to the quantity measured (after VIM)
3.1.28
unit of measurement

measurable quantity, defined and adopted by convention, with which other quantities of the same

dimension are compared in order to express their magnitudes relative to that quantity (after VIM)

NOTE The word unit is also used in statistics and in counting for what is here called entity (Subclause

3.1.10).
3.1.29
value of quantity

magnitude of a measurable quantity generally expressed as a number multiplied by a unit of

measurement (after VIM)
3.2 Abbreviations, initialisms and acronyms

BIPM International Bureau of Weights and Measures = Bureau International des Poids et

Mesures
CEN European Committee for Standardization = Comité Européen de Normalisation =
Europäisches Komitee für Normung

CGPM General Conference on Weights and Measures = Conférence Générale des Poids et

Mesures

CQU IUPAC Commission on Quantities and Units in Clinical Chemistry and IFCC Committee

on Quantities and Units
EDIFACT Electronic Data Interchange for Administration, Commerce and Transport
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SIST EN 12435:2006
EN 12435:2006 (E)
ENV European Prestandard = Prénorme Européenne = Europäisches Vornorm
EU European Union
ICRP International Council on Radiological Protection
ICRU International Commission on Radiation Units and Measurements
ICSH International Council on Standardization in Haematology
IEC International Electrotechnical Commission
IFCC International Federation of Clinical Chemistry
ISO International Organization for Standardization
IUBMB International Union of Biochemistry and Molecular Biology
IUPAC International Union of Pure and Applied Chemistry
IUPAC-CT IUPAC Commission on Toxicology
IUPAP International Union of Pure and Applied Physics
OIML International Organization for Legal Metrology
OSI Open Systems Interconnection
SEPCR European Society for Clinical Respiratory Physiology
SI International System of Units
VIM International vocabulary of basic and general terms in metrology (Clause 2)
WHA World Health Assembly
WHO World Health Organization
WMO World Meteorological Organization
4 Elements of data in a measurable quantity and its result

4.1 A measurement can be expressed in a logical statement, which includes the following possible

elements:
 system
 component
 kind-of-quantity
 relational operator
 numerical value
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SIST EN 12435:2006
EN 12435:2006 (E)
 unit of measurement
 uncertainty.
4.2 In symbolic language
q = {q} · [q] ± {uc} ·[q]

where q is any measurable quantity (designated by a kind-of-quantity, a system and any component), [q]

is a unit of measurement of the quantity q and {q} is its numerical value in that unit, {uc} is the numerical

value of combined uncertainty in that same unit.
EXAMPLE
Blood (venous; fasting patient) – Glucose; substance concentration
-1 -1

= 4,9 mmol L ± 0,2 mmol L where the quantity after the ± is combined standard uncertainty

The relation sometimes requires other relational operators than equals (=), such as < (is less

4.3

than), > (is more than), ≤ (is less than or equal to), ≥ (is more than or equal to), ≈ (is approximately

equal to) or ≠ (is not equal to) (ISO 31-11: 1992, Clause 3).

NOTE ENV 1614 "Medical informatics – Messages for the exchange of laboratory information" concentrates

on the elements of information on the left of the relational operator. This ENV complements that work and

concentrates on the right of the relational operator.
5 Units for reporting information in health sciences
5.1 Representation of results of measurements

In the representation of results of measurements, the unitary expressions shall include any of the

following:
 SI units (Clauses 5.1 to 5.3)
 units formed from SI units by use of prefix symbols (Clause 5.4)
 certain off-system units (Clause 5.5)
 certain dimensionless units (Clause 5.6).

5.1.1 Annex A provides conversion factors with which algorithms can be designed to convert other

units in local use and Annex C provides some criteria for conversion between kinds-of-quantity.

5.1.2 Table 1 lists SI base units each with its associated base kind-of-quantity. Definitions of the SI

base units are given in Annex A. Number of entities is sometimes also treated as base and has the

coherent SI unit `one'. For the choice of kilogram (with a prefix) as a base unit see Clause 5.4.6.

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SIST EN 12435:2006
EN 12435:2006 (E)

Table 1 —Base kinds-of-quantity, base units and their dimensional symbols in the International System

of Units (SI). The base kinds-of-quantity are in the sequence used by CGPM and in Annex A. Entries

begin with the references (Ref.) to that annex.
Base kind-of-quantity Base unit
Ref. Dimension
name symbol name symbol
number (of
A.1 N one 1 1
entities)
A.2 length l metre m L
A.10 mass m kilogram kg M
A.19 time t second s T
electrical
A.66 I ampere A I
current
thermodyna
A.87 mic T, ϑ kelvin K Θ
temperature
luminous
A.102 Iv candela cd J
intensity
amount-of-su
A.107 n mole mol N
bstance
5.2 Derived coherent units of SI and mathematical operations with units

5.2.1 Most coherent units of derived kinds-of-quantity are represented with compound units

obtained by multiplication or division or both of the component base units. Such expressions require

the mathematical operations of multiplication, division and raising to a power.
-2 -1

EXAMPLE Mole per square metre second (mol m s ) is the SI-coherent compound unit of areic

substance rate (Annex A.120).

5.2.2 Multiplication between units shall be represented by either a space, by a half-raised point

( · ) or by raising to a power.

EXAMPLES The product of pascal and second (called pascal second) is represented as Pa s or Pa · s.

-1 -1 -1
The product of 2 Pa s with 5 s is 2 Pa s X 5 s = (2 Pa s) · (5 s ) = 10 Pa.

NOTE 1 The multiplication sign X is not recommended by ISO 31-0 for expression of units.

NOTE 2 The space between a numerical value and a unit also represents multiplication.

2 3

NOTE 3 Raising a unit u to a power is usually expressed as `unit squared' (u ), `unit cubed' (u ) or `unit to the

fourth power' (u ). For units of length, the designations `square unit' and `cubic unit' (e.g. square metre and cubic

metre) are used as long as the derived quantity can be viewed as an area and a volume, respectively. Otherwise

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SIST EN 12435:2006
EN 12435:2006 (E)

designations like metre squared and metre cubed are used. In Annex A, only designations like square metre and

cubic metre are listed.

5.2.3 Division of units shall be represented by multiplication of negative powers (example above)

or by a slash (/). Not more than one slash shall be used in one compound unit, unless brackets are

used in the expression to avoid ambiguity.
-2 -1 -2 -1 2 2 2
EXAMPLE mol m s = mol·m ·s = mol/(m s) = (mol/m )/s but not mol/m /s
5.3 Derived coherent units of SI with special names and symbols

Special names or symbols, usually both, are allowed for certain derived SI units (Table 2).

5.4 Multiples and submultiples of units: prefix names and symbols

5.4.1 If a system of units is chosen with only one unit for each dimension, there are bound to be

some very large and very small numerical values, which can be expressed more briefly by use of

powers of 10, such that numerical values (i.e. the mantissas) can almost always be between 0,1 and

1000 (Subclause 6.1.3).
EXAMPLES
Molar number constant, N , ≈ 602 213 670 000 000 000 000 000 mol
21 -1
= 602,213 67·10 mol
Rest mass of an electron, m ≈ 0,000 000 000 000 000 000 000 000 000 000 9 kg
-30
= 0,9·10 kg

5.4.2 Instead of using powers of 10 with numerical values, decimal prefixes may be attached to SI

units. The prefixes

Table 2 — Kinds-of-quantity associated with derived SI units with special names or symbols. The

sequence of the list is as in Annex A, to which the references (Ref.) apply, essentially by order of

dimension (Table 1) with increasing magnitude of powers of those dimensions, first positive and then

negative. The trivial names of some kinds-of-quantity (A.44, equivalent dose) imply also an unnamed

generalized component (marked by the modulus sign, |, in the systematic name). Systematic names of

electrical and luminous kinds-of-quantity are based on electrical charge (unit C = A s) and quantity of

light (unit lm s = cd sr s), respectively. The distinction electric and electrical is a non-normative mental

aid in marking those kinds-of-quantity in which electrical charge forms part of the denominator and

numerator, respectively, of the definition. The name and symbol of the katal have been recognized by

IUPAC, IFCC, IUBMB and WHO; other units are recognized also by BIPM (1991). The symbols t, ϑ and

Φ have several meanings in Table 1 and 2, those of  being distinguished here by subscripts.

Kind-of-quantity
Unit
Ref. name Definition in SI-base units
symbol
symbol name
A.1 radian rad m m = 1
plane angle γ, ϑ α, β,
2 -2
A.1 solid angle Ω steradian sr m m = 1
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SIST EN 12435:2006
EN 12435:2006 (E)
A.20 number rate | of hertz Hz s
f, ν
regular events;
frequency
A.20 radioactivity A becquerel Bq s
2 -2
A.44 massic energy | of D gray Gy m s
ionizing radiation
absorbed; absorbed
dose
2 -2
A.44 effective massic sievert Sv m s
energy | of ionizing
radiation absorbed;
equivalent dose
A.48 force F newton N kg m s
-1 -2
A.50 pressure p pascal Pa kg m s
2 -2
A.51 energy E, Q joule J kg m s
2 -3
A.58 energy rate; power watt W kg m s
P, Φ
A.61 electrical charge Q coulomb C A s
-1 -2
A.72 magnetic induction; B tesla T kg A s
-1 -1
magnetic flux = kg C s
density
2 -1 -2
A.74 magnetic flux weber Wb kg m A s
2 -1 -1
= kg m C s
2 -1 -3
A.76 electric potential U, V volt V kg m A s
2 -1 -2
difference = kg m C s
2 -2 -2
A.78 mutual inductance L henry H kg m A s
2 -2
= kg m C
2 3 -1 -2
A.80 electrical G siemens S A s kg m
conductance
2 -1 -2
= s C kg m
2 -2 -3
A.81 electric resistance R ohm kg m A s
2 -2 -1
= kg m C s
...

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