SIST EN ISO 13849-2:2008
(Main)Safety of machinery - Safety-related parts of control systems - Part 2: Validation (ISO 13849-2:2003)
Safety of machinery - Safety-related parts of control systems - Part 2: Validation (ISO 13849-2:2003)
This European Standard specifies the procedures and conditions to be followed for the validation by analysis and testing of:;the safety functions provided, and;the category achieved of the safety-related parts of the control system in complianc e with EN 954-1 (ISO 13849-1), using the design rationale prov ided by the designer.
Sicherheit von Maschinen - Sicherheitsbezogene Teile von Steuerungen - Teil 2: Validierung (ISO 13849-2:2003)
Diese Europäische Norm legt die Vorgehensweisen und Bedingungen in Übereinstimmung mit EN 954-1 (ISO 13849-1) fest, die bei der Validierung durch Analyse und Prüfung zu befolgen sind, für:
- die vorgesehenen Sicherheitsfunktionen und
- die ausgeführten Kategorien
der sicherheitsbezogenen Teile von Steuerungen, bei Anwendung der durch den Konstrukteur vorgesehenen sinnvollen Gestaltung.
Diese Europäische Norm gibt keine vollständigen Validierungsanforderungen für programmierbare elektronische Systeme und kann deshalb die Anwendung anderer Normen erfordern.
ANMERKUNG CEN/TC 114/WG 6 schlägt vor, sich eingehender mit der Validierung von programmierbaren elektronischen Systemen bei der Erarbeitung der Änderung der EN 954-1 (ISO 13849-1) zu befassen. Eine Anwendungsnorm für Maschinen (Entwurf IEC 62061), der die IEC 61508 zu Grunde liegt, wird zurzeit erarbeitet. Die Anforderungen für programmierbare elektronische Systeme, einschließlich der damit verbundenen Software, sind in IEC 61508 enthalten.
Sécurité des machines - Parties des systèmes de commande relatifs à la sécurité - Partie 2: Validation (ISO 13849-2:2003)
L'ISO 13849-2:2003 spécifie les procédures et conditions à suivre pour la validation par analyse et par essais:
des fonctions de sécurité assurées, et
de la catégorie atteinte
par les parties de système de commande relatives à la sécurité en conformité avec l'EN 954-1 (ISO 13849-1), en utilisant le raisonnement de conception fourni par le concepteur.
La présente Norme internationale ne donne pas de prescriptions complètes de validation pour les systèmes électroniques programmables et peut par conséquent nécessiter l'utilisation d'autres normes.
Varnost strojev - Z varnostjo povezani deli krmilnih sistemov - 2. del: Potrjevanje (ISO 13849-2:2003)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 13849-2:2008
01-oktober-2008
1DGRPHãþD
SIST EN ISO 13849-2:2004
Varnost strojev - Z varnostjo povezani deli krmilnih sistemov - 2. del: Potrjevanje
(ISO 13849-2:2003)
Safety of machinery - Safety-related parts of control systems - Part 2: Validation (ISO
13849-2:2003)
Sicherheit von Maschinen - Sicherheitsbezogene Teile von Steuerungen - Teil 2:
Validierung (ISO 13849-2:2003)
Sécurité des machines - Parties des systèmes de commande relatifs à la sécurité -
Partie 2: Validation (ISO 13849-2:2003)
Ta slovenski standard je istoveten z: EN ISO 13849-2:2008
ICS:
13.110 Varnost strojev Safety of machinery
SIST EN ISO 13849-2:2008 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 13849-2:2008
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SIST EN ISO 13849-2:2008
EUROPEAN STANDARD
EN ISO 13849-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2008
ICS 13.110 Supersedes EN ISO 13849-2:2003
English Version
Safety of machinery - Safety-related parts of control systems -
Part 2: Validation (ISO 13849-2:2003)
Sécurité des machines - Parties des systèmes de Sicherheit von Maschinen - Sicherheitsbezogene Teile von
commande relatifs à la sécurité - Partie 2: Validation (ISO Steuerungen - Teil 2: Validierung (ISO 13849-2:2003)
13849-2:2003)
This European Standard was approved by CEN on 18 May 2008.
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 CEN Management Centre 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 CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13849-2:2008: E
worldwide for CEN national Members.
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SIST EN ISO 13849-2:2008
EN ISO 13849-2:2008 (E)
Contents Page
Foreword.3
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC, amended by Directive 98/79/EC .4
Annex ZB (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC .5
2
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SIST EN ISO 13849-2:2008
EN ISO 13849-2:2008 (E)
Foreword
The text of ISO 13849-2:2003 has been prepared by Technical Committee ISO/TC 199 “Safety of machinery”
of the International Organization for Standardization (ISO) and has been taken over as EN ISO 13849-2:2008
by Technical Committee CEN/TC 114 “Safety of machinery” the secretariat of which is held by DIN.
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 November 2008, and conflicting national standards shall be withdrawn
at the latest by December 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 13849-2:2003.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EC Directive(s).
For relationship with EC Directive(s), see informative Annexes ZA and ZB, which are integral part of this
document.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, 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 the United Kingdom.
Endorsement notice
The text of ISO 13849-2:2003 has been approved by CEN as a EN ISO 13849-2:2008 without any
modification.
3
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SIST EN ISO 13849-2:2008
EN ISO 13849-2:2008 (E)
Annex ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC, amended by Directive 98/79/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 98/37/EC, amended by Directive 98/79/EC.
Once this standard is cited in the Official Journal of the European Communities under that Directive and has
been implemented as a national standard in at least one Member State, compliance with the normative
clauses of this standard confers, within the limits of the scope of this standard, a presumption of conformity
with Essential Requirements 1.2.1 and 1.2.7 of Annex I of that Directive and associated EFTA regulations.
WARNING: Other requirements and other EU Directives may be applicable to the products falling within the
scope of this standard.
4
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SIST EN ISO 13849-2:2008
EN ISO 13849-2:2008 (E)
Annex ZB
(informative)
Relationship between this European Standard and the Essential Requirements of
EU Directive 2006/42/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive Machinery 2006/42/EC.
Once this standard is cited in the Official Journal of the European Communities under that Directive and has
been implemented as a national standard in at least one Member State, compliance with the normative
clauses of this standard confers, within the limits of the scope of this standard, a presumption of conformity
with Essential Requirements 1.2.1 of Annex I of that Directive and associated EFTA regulations.
WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling within
the scope of this standard.
5
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SIST EN ISO 13849-2:2008
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SIST EN ISO 13849-2:2008
INTERNATIONAL ISO
STANDARD 13849-2
First edition
2003-08-15
Safety of machinery — Safety-related
parts of control systems —
Part 2:
Validation
Sécurité des machines — Parties des systèmes de commande relatifs
à la sécurité —
Partie 2: Validation
Reference number
ISO 13849-2:2003(E)
©
ISO 2003
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
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ii © ISO 2003 – All rights reserved
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 13849-2 was prepared by the European Committee for Standardization (CEN) in collaboration with
Technical Committee ISO/TC 199, Safety of machinery, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
Throughout the text of this document, read “.this European Standard.” to mean “.this International
Standard.”.
ISO 13849 consists of the following parts, under the general title Safety of machinery — Safety-related parts
of control systems:
— Part 1: General principles for design
— Part 2: Validation
— Part 100: Guidelines for the use and application of ISO 13849-1
© ISO 2003 – All rights reserved iii
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
Page
Contents
Foreword.v
Introduction .vi
1 Scope .1
2 Normative references .1
3 Validation process .1
3.1 Validation principles.1
3.2 Generic fault lists.3
3.3 Specific fault lists .3
3.4 Validation plan.3
3.5 Information for validation.4
3.6 Validation record.5
4 Validation by analysis .5
4.1 General.5
4.2 Analysis techniques .6
5 Validation by testing.6
5.1 General.6
5.2 Measurement uncertainty .7
5.3 Higher requirements.7
5.4 Number of test samples .7
6 Validation of safety functions.8
7 Validation of categories .8
7.1 Analysis and testing of categories.8
7.2 Validation of category specifications .9
7.3 Validation of combination of safety–related parts .10
8 Validation of environmental requirements.10
9 Validation of maintenance requirements .11
Annex A (informative) Validation tools for mechanical systems .12
Annex B (informative) Validation tools for pneumatic systems .17
Annex C (informative) Validation tools for hydraulic systems .28
Annex D (informative) Validation tools for electrical systems .38
Bibliography .49
iv © ISO 2003 – All rights reserved
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
Foreword
This document EN ISO 13849-2:2003 has been prepared by Technical Committee CEN /TC 114, "Safety of
machinery", the secretariat of which is held by DIN in collaboration with Technical Committee ISO/TC 199 "Safety
of machinery".
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 February 2004, and conflicting national standards shall be withdrawn at the latest
by February 2004.
This document has been prepared under a mandate given to CEN by the European Commission and the European
Free Trade Association and supports essential requirements of EC Directive(s).
Annexes A to D are informative and structured as given in Table 1.
Table 1 — Structure of the clauses of annexes A to D
Annex Technology List of basic List of well- List of well- Fault lists and
safety tried safety tried fault
principles principles components exclusions
Clause
A Mechanical A.2 A.3 A.4 A.5
B Pneumatic B.2 B.3 B.4 B.5
C Hydraulic C.2 C.3 C.4 C.5
D Electrical (includes electronics) D.2 D.3 D.4 D.5
This document includes a Bibliography.
EN ISO 13849 consists of the following parts, under the general title "Safety of machinery – Safety-related parts of
control systems":
Part 1: General principles for design
Part 2: Validation
Part 100: Guidelines for the use and application of EN ISO 13849-1.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal,
Slovakia, Spain, Sweden, Switzerland and the United Kingdom.
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
Introduction
For the use in the European Union, this part of EN ISO 13849 has the status of a generic safety standard (type B1).
This European Standard specifies the validation process, including both analysis and testing, for the safety
functions and categories for the safety–related parts of control systems. Descriptions of the safety functions and
the requirements for the categories are given in EN 954-1 (ISO 13849-1) which deals with the general principles for
design. Some requirements for validation are general and some are specific to the technology used.
EN ISO 13849-2 also specifies the conditions under which the validation by testing of the safety-related parts of
control systems should be carried out.
EN 954-1 (ISO 13849-1) specifies the safety requirements and gives guidance on the principles for the design [see
EN 292-1:1991 (ISO/TR 12100:1992), 3.11] of the safety-related parts of control systems. For these parts it
specifies categories and describes the characteristics of their safety functions, regardless of the type of energy
used. Additional advice on EN 954-1 (ISO 13894-1) is given in CR 954-100 (ISO/TR 13849-100).
The achievement of the requirements can be validated by any combination of analysis (see clause 4) and testing
(see clause 5). The analysis should be started as early as possible within the design process.
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
1 Scope
This European Standard specifies the procedures and conditions to be followed for the validation by analysis and
testing of:
the safety functions provided, and
the category achieved
of the safety-related parts of the control system in compliance with EN 954-1 (ISO 13849-1), using the design
rationale provided by the designer.
This European Standard does not give complete validation requirements for programmable electronic systems and
therefore can require the use of other standards.
NOTE CEN/TC 114/WG 6 proposes to deal in more detail with the validation of programmable electronic systems in the
elaboration of the revision to EN 954-1 (ISO 13849-1). An application standard for machinery (draft IEC 62061), based on IEC
61508, is under preparation. Requirements for programmable electronic systems, including embedded software, are given in
IEC 61508.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this European
Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
EN 292-1:1991 (ISO/TR 12100:1992), Safety of machinery — Basic concepts, general principles for design —
Part 1: Basic terminology, methodology.
EN 954-1:1996 (ISO 13849-1:1999), Safety of machinery — Safety-related parts of control systems — Part 1:
General principles for design.
3 Validation process
3.1 Validation principles
The purpose of the validation process is to confirm the specification and the conformity of the design of the safety-
related parts of the control system within the overall safety requirements specification of the machinery.
The validation shall demonstrate that each safety-related part meets the requirements of EN 954-1 (ISO 13849-1),
in particular:
the specified safety characteristics of the safety functions provided by that part, as set out in the design
rationale, and
the requirements of the specified category [see EN 954-1:1996 (ISO 13849-1:1999), clause 6].
Validation should be carried out by persons who are independent of the design of the safety-related part(s).
rd
NOTE Independent person does not necessarily mean that a 3 party test is required.
The degree of independence should reflect the safety performance of the safety-related part.
Validation consists of applying analysis (see clause 4) and, if necessary, executing tests (see clause 5) in
accordance with the validation plan. Figure 1 gives an overview of the validation process. The balance between the
analysis and/or testing depends on the technology.
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
The analysis should be started as early as possible and in parallel with the design process, so that problems can
be corrected early whilst they are still relatively easy to correct, i. e. during steps 3 and 4 of EN 954-1:1996
(ISO 13849-1:1999), 4.3. It can be necessary for some parts of the analysis to be delayed until the design is well
developed.
For large systems, due to the size, complexity or integrated form (with the machinery) of the control system, special
arrangements may be made for:
validation of the safety-related parts of the control system separately before integration including simulation of
the appropriate input and output signals;
validation of the effects of integrating safety-related parts into the remainder of the control system within the
context of its use in the machine.
Figure 1 — Overview of the validation process
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
3.2 Generic fault lists
The validation process involves consideration of behaviour of the safety-related part(s) of the control system for all
faults to be considered. A basis for fault consideration is given in the fault lists in the informative annexes (A.5, B.5,
C.5 and D.5) which are based on experience. The generic fault lists contain:
the components/elements to be included, e. g. conductors/cables (see D.5.2);
the faults to be taken into account, e. g. short circuits between conductors;
the permitted fault exclusions;
a remarks section giving the reasons for the fault exclusions.
Only permanent faults are taken into account.
3.3 Specific fault lists
A specific product-related fault list shall be generated as a reference document for the validation process of the
safety-related part(s). The list can be based on the appropriate generic list(s) found in the annex(es).
Where the specific product-related fault list is based on the generic list(s) it shall state:
the faults taken from the generic list(s) to be included;
any other relevant faults to be included but not given in the generic list (e. g. common mode faults);
the faults taken from the generic list(s) which may be excluded and can meet at least the criteria given in the
generic list(s) [see EN 954-1:1996 (ISO 13849-1:1999), 7.2];
and, exceptionally
any other relevant faults, from the generic list but not permitted for exclusion by the generic list(s), together
with a justification and a rationale for its exclusion [see EN 954-1:1996 (ISO 13849-1:1999), 7.2].
Where this list is not based on the generic list(s) the designer shall give the rationale for fault exclusions.
3.4 Validation plan
The validation plan shall identify and describe the requirements for carrying out the validation process of the
specified safety functions and their categories.
The validation plan shall also identify the means to be employed to validate the specified safety functions and
categories. It shall set out, where appropriate:
a) the identity of the specification documents;
b) the operational and environmental conditions;
c) the basic safety principles (see A.2, B.2, C.2 and D.2);
d) the well-tried safety principles (see A.3, B.3, C.3 and D.3);
e) the well-tried components (see A.4 and D.4);
f) the fault assumptions and fault exclusions to be considered e. g. from the informative fault lists in A.5, B.5, C.5
and D.5;
g) the analyses and tests to be applied.
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
Safety-related parts which have previously been validated to the same specification need only a reference to that
previous validation.
3.5 Information for validation
The information required for validation will vary with the technology used, the category(ies) to be demonstrated, the
design rationale of the system and the contribution of the safety-related parts of control systems to the reduction of
the risk. Documents containing sufficient information from the list below shall be included in the validation process
to demonstrate the category(ies) and the safety function(s) of the safety-related parts which have been achieved:
a) specification(s) of the expected performance, of the safety functions and categories;
b) drawings and specifications, e. g. for mechanical, hydraulic and pneumatic parts, printed circuit boards,
assembled boards, internal wiring, enclosure, materials, mounting;
c) block diagram(s) with functional description of the blocks;
d) circuit diagram(s) including interfaces/connections;
e) functional description of the circuit diagram(s);
f) time sequence diagram(s) for switching components, signals relevant for safety;
g) description of the relevant characteristics of components previously validated;
h) for other safety-related parts (excluding those listed in g)) component lists with item designations, rated values,
tolerances, relevant operating stresses, type designation, failure rate data and component manufacturer and
any other data relevant for safety;
i) analysis of all relevant faults (see also 3.2) listed e. g. in A.5, B.5, C.5 and D.5, including the justification of any
excluded faults;
j) an analysis of the influence of processed materials;
Category specific information in accordance with Table 2. Where software is relevant to the safety function(s), the
software documentation shall include:
1) a specification which is clear and unambiguous and states the safety performance the software is required
to achieve, and
2) evidence that the software is designed to achieve the required safety performance, and
3) details of tests (in particular test reports) carried out to prove that the required safety performance is
achieved.
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SIST EN ISO 13849-2:2008
ISO 13849-2:2003(E)
Table 2 — Documentation requirements for categories
Documentation requirement Category for which
documentation is
required
B 1 234
Basic safety principles X X XXX
Expected operating stresses X X XXX
Influences of processed material X X XXX
Performance during other relevant external influences X X XXX
Well–tried components – X –––
Well–tried safety principles – X XXX
The check procedure of the safety function(s) – – X ––
Checking intervals, when specified – – X ––
Foreseeable, single faults considered in the design and the detection method used – – x XX
The common mode failures identified and how prevented – – – XX
The foreseeable, single faults excluded – – – XX
The faults to be detected – – x XX
The variety of accumulations of faults considered in the design – – – – X
How the safety function is maintained in the case of each of the fault(s) – – – XX
How the safety function is maintained for each of
...
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