EN ISO 14121-1:2007

SLOVENSKI STANDARD
01-november-2007
9DUQRVWVWURMHY2FHQDWYHJDQMDGHO1DþHOD,62
Safety of machinery - Risk assessment - Part 1: Principles (ISO 14121-1:2007)
Sicherheit von Maschinen - Risikobeurteilung - Teil 1: Leitsätze (ISO 14121-1:2007)
Sécurité des machines - Appréciation du risque - Partie 1: Principes (ISO 14121-1:2007)
Ta slovenski standard je istoveten z: EN ISO 14121-1:2007
ICS:
13.110 Varnost strojev Safety of machinery
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 14121-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2007
ICS 13.110 Supersedes EN 1050:1996
English Version
Safety of machinery - Risk assessment - Part 1: Principles (ISO
14121-1:2007)
Sécurité des machines - Appréciation du risque - Partie 1: Sicherheit von Maschinen - Risikobeurteilung - Teil 1:
Principes (ISO 14121-1:2007) Leitsätze (ISO 14121-1:2007)
This European Standard was approved by CEN on 4 August 2007.
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.
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© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 14121-1:2007: E
worldwide for CEN national Members.

Contents Page
Foreword.3

Foreword
This document (EN ISO 14121-1:2007) has been prepared by Technical Committee ISO/TC 199 "Safety of
machinery" in collaboration with 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 March 2008, and conflicting national standards shall be withdrawn at
the latest by March 2008.
This document supersedes EN 1050:1996.
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 Annex ZA and ZB, which is an 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 14121-1:2007 has been approved by CEN as a EN ISO 14121-1:2007 without any
modification.
Annex ZA
(informative)
Relationship between this International Standard and the Essential Requirements of
EU Directive 98/37/EC, amended by Directive 98/79/EC

This International 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, Machinery, 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 the relevant Essential Requirements of that Directive and associated EFTA regulations.

WARNING — Other requirements and other EC Directives may be applicable to the product(s) falling within
the scope of this standard.
Annex ZB
(informative)
Relationship between this International Standard and the Essential Requirements of
EU Directive 2006/42/EC
This International Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide one means of conforming to Essential Requirements of
the New Approach Directive 2006/42/EC on machinery.

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 the relevant Essential Requirements 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.
INTERNATIONAL ISO
STANDARD 14121-1
First edition
2007-09-01
Safety of machinery — Risk
assessment —
Part 1:
Principles
Sécurité des machines — Appréciation du risque —
Partie 1: Principes
Reference number
ISO 14121-1:2007(E)
©
ISO 2007
ISO 14121-1:2007(E)
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ii © ISO 2007 – All rights reserved

ISO 14121-1:2007(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 1
4 General principles. 4
4.1 Basic concepts. 4
4.2 Information for risk assessment . 5
5 Determination of limits of machinery . 6
5.1 General. 6
5.2 Use limits . 7
5.3 Space limits . 7
5.4 Time limits . 7
5.5 Other limits . 8
6 Hazard identification. 8
7 Risk estimation . 9
7.1 General. 9
7.2 Elements of risk . 9
7.3 Aspects to be considered during risk estimation . 12
8 Risk evaluation. 13
8.1 General. 13
8.2 Achievement of adequate risk reduction . 14
8.3 Comparison of risks . 15
9 Documentation. 15
Annex A (informative) Examples of hazards, hazardous situations and hazardous events. 16
Bibliography . 28

ISO 14121-1:2007(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 14121-1 was prepared by Technical Committee ISO/TC 199, Safety of machinery.
This first edition of ISO 14121-1 cancels and replaces ISO 14121:1999, of which it constitutes a technical
revision.
ISO 14121 consists of the following parts, under the general title Safety of machinery — Risk assessment:
⎯ Part 1: Principles
⎯ Part 2: Practical guidance and examples of methods [Technical Report]

iv © ISO 2007 – All rights reserved

ISO 14121-1:2007(E)
Introduction
The structure of safety standards in the field of machinery is as follows.
a) Type-A standards (basic standards) give basic concepts, principles for design, and general aspects that
can be applied to machinery.
b) Type-B standards (generic safety standards) deal with one or more safety aspect(s) or one or more
type(s) of safeguards that can be used across a wide range of machinery:
⎯ type-B1 standards on particular safety aspects (e.g. safety distances, surface temperature, noise);
⎯ type-B2 standards on safeguards (e.g. two-hands controls, interlocking devices, pressure sensitive
devices, guards).
c) Type-C standards (machine safety standards) deal with detailed safety requirements for a particular
machine or group of machines.
This part of ISO 14121 is a type-A standard as stated in ISO 12100-1.
When provisions of a type-C standard are different from those which are stated in type-A or type-B standards,
the provisions of the type-C standard take precedence over the provisions of the other standards for machines
that have been designed and built according to the provisions of the type-C standard.
The purpose of this type-A standard is to describe principles for a consistent systematic procedure for risk
assessment as stated in ISO 12100-1:2003, Clause 5.
This part of ISO 14121 gives guidance for decisions related to the design of machinery and will assist in the
preparation of consistent and appropriate type-B and type-C standards, so that machines can be produced that
are safe for their intended use in accordance with the methodology given in ISO 12100.
Annex A gives, in separate tables, examples of hazards, hazardous situations and hazardous events, so as to
clarify these concepts and assist the designer in the process of hazard identification.
The practical use of a number of methods for each stage of risk assessment is described ISO/TR 14121-2,
which also gives some guidance on how the selection of protective measures (in accordance with ISO 12100)
can reduce the different elements of risk in relation to Figure 2 of this part of ISO 14121.
This part of ISO 14121 can be incorporated in training courses and manuals where appropriate to give basic
instruction on risk assessment.
INTERNATIONAL STANDARD ISO 14121-1:2007(E)

Safety of machinery — Risk assessment —
Part 1:
Principles
1 Scope
This part of ISO 14121 establishes general principles intended to be used to meet the risk reduction objectives
established in ISO 12100-1:2003, Clause 5. These principles of risk assessment bring together knowledge
and experience of the design, use, incidents, accidents and harm related to machinery in order to assess the
risks posed during the relevant phases of the life cycle of a machine.
This part of ISO 14121 provides guidance on the information that will be required to enable risk assessment to
be carried out. Procedures are described for identifying hazards and estimating and evaluating risk.
It also gives guidance on the making of decisions relating to the safety of machinery and on the type of
documentation required to verify the risk assessment carried out.
It is not applicable to risks posed to domestic animals, property or the environment.
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 12100-1:2003, Safety of machinery — Basic concepts, general principles for design — Part 1: Basic
terminology, methodology
ISO 12100-2:2003, Safety of machinery — Basic concepts, general principles for design — Part 2: Technical
principles and specifications
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
harm
physical injury or damage to health
[ISO 12100-1:2003, definition 3.5]
ISO 14121-1:2007(E)
3.2
hazard
potential source of harm
NOTE 1 The term “hazard” can be qualified in order to define its origin (e.g. mechanical hazard, electrical hazard) or
the nature of the potential harm (e.g. electric shock hazard, cutting hazard, toxic hazard, fire hazard).
NOTE 2 The hazard envisaged in this definition:
⎯ either is permanently present during the intended use of the machine (e.g. motion of hazardous moving elements,
electric arc during a welding phase, unhealthy posture, noise emission, high temperature);
⎯ or can appear unexpectedly (e.g. explosion, crushing hazard as a consequence of an unintended / unexpected start-
up, ejection as a consequence of a breakage, fall as a consequence of acceleration / deceleration)
[ISO 12100-1:2003, definition 3.6]
3.3
hazard zone
danger zone
any space within and/or around machinery in which a person can be exposed to a hazard
[ISO 12100-1:2003, definition 3.10]
3.4
hazardous event
event that can cause harm
NOTE A hazardous event can occur over a short period of time or over an extended period of time.
3.5
hazardous situation
circumstance in which a person is exposed to at least one hazard
NOTE The exposure can result in harm immediately or over a period of time.
[ISO 12100-1:2003, definition 3.9]
3.6
intended use of a machine
use of a machine in accordance with the information provided in the instructions for use
[ISO 12100-1:2003, definition 3.22]
3.7
machinery
machine
assembly of linked parts or components, at least one of which moves, with the appropriate machine actuators,
control and power circuits, joined together for a specific application, in particular for the processing, treatment,
moving or packaging of a material
NOTE The term “machinery” also covers an assembly of machines which, in order to achieve the same end, are
arranged and controlled so that they function as an integral whole.
[ISO 12100-1:2003, definition 3.1]
3.8
malfunction
failure of a machine to perform an intended function
NOTE For examples, see ISO 12100-1:2003, 5.3 b), item 2).
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ISO 14121-1:2007(E)
3.9
protective measure
measure intended to achieve risk reduction
NOTE 1 It is implemented:
⎯ by the designer (inherently safe design, safeguarding and complementary protective measures, information for use);
⎯ or by the user (organization: safe working procedures, supervision, permit-to-work systems; provision and use of
additional safeguards; use of personal protective equipment; training).
NOTE 2 See ISO 12100-1:2003, Figure 1.
[ISO 12100-1:2003, definition 3.18]
3.10
reasonably foreseeable misuse
use of a machine in a way not intended by the designer, but which may result from readily predictable human
behaviour
[ISO 12100-1:2003, definition 3.23]
3.11
residual risk
risk remaining after protective measures have been taken
NOTE See ISO 12100-1:2003, Figure 1.
[ISO 12100-1:2003, definition 3.12]
3.12
risk
combination of the probability of occurrence of harm and the severity of that harm
[ISO 12100-1:2003, definition 3.11]
3.13
risk analysis
combination of the specification of the limits of the machine, hazard identification and risk estimation
[ISO 12100-1:2003, definition 3.14]
3.14
risk assessment
overall process comprising a risk analysis and a risk evaluation
[ISO 12100-1:2003, definition 3.13]
3.15
risk estimation
definition of likely severity of harm and probability of its occurrence
[ISO 12100-1:2003, definition 3.15]
3.16
risk evaluation
judgement, on the basis of risk analysis, of whether the risk reduction objectives have been achieved
[ISO 12100-1:2003, definition 3.16]
ISO 14121-1:2007(E)
3.17
task
specific activity performed by one or more persons on or in the vicinity of the machine during its lifecycle
4 General principles
4.1 Basic concepts
Risk assessment is a series of logical steps to enable, in a systematic way, the analysis and evaluation of the
risks associated with machinery. Risk assessment is followed, whenever necessary, by risk reduction as
described in ISO 12100-1:2003, Clause 5. Iteration of this process can be necessary to eliminate hazards as
far as practicable and to adequately reduce risks by the implementation of protective measures.
Risk assessment includes the following (see Figure 1):
a) risk analysis:
1) determination of the limits of the machinery (see Clause 5);
2) hazard identification (see Clause 6);
3) risk estimation (see Clause 7);
b) risk evaluation (see Clause 8).
Risk analysis provides information required for the risk evaluation, which in turn allows judgements to be
made about whether or not risk reduction is required.
These judgments shall be supported by a qualitative, or where appropriate, a quantitative, estimate of the risk
associated with the hazards present on the machinery
NOTE A quantitative approach can be appropriate when useful data is available. However, a quantitative approach is
restricted by the useful data that are available and/or the limited resources of those conducting the risk assessment.
Therefore, in many applications, only qualitative risk estimation will be possible.
The risk assessment shall be conducted so that it is possible to document the procedure that has been
followed and the results that have been achieved (see Clause 9).
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ISO 14121-1:2007(E)
Figure 1 — Iterative process for reducing risk
4.2 Information for risk assessment
The information for risk assessment should include the following:
a) related to machinery description:
1) user specifications;
2) anticipated machinery specifications, including
i) description of the various phases of the whole life cycle of the machinery,
ii) design drawings or other means of establishing the nature of the machinery, and
iii) required energy sources and how they are supplied;
ISO 14121-1:2007(E)
3) documentation on previous designs of similar machinery, if relevant;
4) information for use of the machinery, as available;
b) related to regulations, standards and other applicable documents:
1) applicable regulations;
2) relevant standards;
3) relevant technical specifications;
4) safety data sheets;
c) related to experience of use:
1) any accident, incident or malfunction history of the actual or similar machinery;
2) the history of damage to health resulting, for example, from emissions (noise, vibration, dust, fumes,
etc.), chemicals used or materials processed by the machinery.
NOTE An incident that has occurred and resulted in harm can be referred to as an “accident”, whereas an
incident that has occurred and that did not result in harm can be referred to as a “near miss” or “dangerous
occurrence”.
d) Relevant ergonomic principles (see ISO 12100-2:2003, 4.8).
The information shall be updated as the design develops or when modifications to the machine are required.
Comparisons between similar hazardous situations associated with different types of machinery are often
possible, provided that sufficient information about hazards and accident circumstances in those situations is
available.
The absence of an accident history, a small number of accidents or low severity of accidents should not be
taken as a presumption of a low risk.
For quantitative analysis, data from data bases, handbooks, laboratories or manufacturers’ specifications may
be used, provided that there is confidence in the suitability of the data. Uncertainty associated with these data
shall be indicated in the documentation (see Clause 9).
5 Determination of limits of machinery
5.1 General
Risk assessment begins with the determination of the limits of the machinery, taking into account all the
phases of the machinery life. This means that the characteristics and performances of the machine or a series
of machines in an integrated process, and the related people, environment and products, should be identified
in terms of the limits of machinery as given in 5.2 to 5.6.
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ISO 14121-1:2007(E)
5.2 Use limits
Use limits includes the intended use and the reasonably foreseeable misuse. Aspects to be taken into account
include the following:
a) the different machine operating modes and the different intervention procedures for the users (including
interventions required by malfunctions of the machine use);
b) the use of the machinery (e.g. industrial, non-industrial and domestic) by persons identified by sex, age,
dominant hand usage, or limiting physical abilities (e.g. visual or hearing impairment, size, strength) — if
specific information is not available, the manufacturer should take into account general information about
the intended user population (e. g. appropriate anthropometric data);
c) the anticipated levels of training, experience or ability of users such as
1) operators,
2) maintenance personnel or technicians,
3) trainees and apprentices, and
4) the general public;
d) exposure of other persons to the hazards associated with the machinery where it can be reasonably
foreseen, including
1) operators working in the vicinity, e.g. operators of adjacent machinery (i.e. persons likely to have a
good awareness of the specific hazards),
2) non-operator employees in the vicinity, e.g. administration staff (i.e. persons with little awareness of
specific hazards but likely to have a good awareness of site safety procedures, authorized routes
etc.), and
3) non-employees in the vicinity, e.g. visitors (i.e. persons likely to have very little awareness of the
machine hazards or the site safety procedures), members of the public including children, where
applicable.
5.3 Space limits
Aspects to be taken into account include
a) range of movement;
b) space requirements for persons to interact with the machine, e.g. during operation and maintenance;
c) human interaction, e.g. “operator-machine” interface; and
d) “machine-power supply” interface.
5.4 Time limits
Aspects to be taken into account include
a) the “life limit” of the machinery and/or of some of its components (e.g. tooling, parts that can wear,
electromechanical components), taking into account its intended use and reasonably foreseeable misuse;
and
b) recommended service intervals.
ISO 14121-1:2007(E)
5.5 Other limits
Examples of other limits:
a) environmental — recommended minimum and maximum temperatures, whether the machine can be
operated indoors or outdoors, in dry or wet weather, in direct sunlight, tolerance to dust and wet, etc.;
b) housekeeping — level of cleanliness required;
c) properties of the material(s) to be processed.
6 Hazard identification
Following the determination of the limits of the machinery (see Clause 5), the essential step in any machine
risk assessment is the systematic identification of reasonably foreseeable hazards, hazardous situations
and/or hazardous events during all phases of the machine life cycle, i.e.:
a) transport, assembly and installation;
b) commissioning;
c) use;
d) de-commissioning, dismantling and disposal.
It is assumed that, when present on machinery, a hazard will sooner or later lead to harm if measures are not
taken to eliminate or provide protective measures.
Only when hazards have been identified can steps be taken to eliminate them or reduce risks. To accomplish
this hazard identification, it is necessary to identify the operations to be performed by the machinery and the
tasks to be performed by persons who interact with it, taking into account the different parts, mechanisms or
functions of the machine, the materials to be processed, if any, and the environment in which the machine can
be used.
Task identification should consider all those tasks associated with all the phases of the machine life cycle
listed above. Task identification should also take into account, but not be limited to, the following task
categories:
⎯ setting;
⎯ testing;
⎯ teaching/programming;
⎯ process/tool changeover;
⎯ start-up;
⎯ all modes of operation;
⎯ feeding machine;
⎯ removal of product from machine;
⎯ stopping the machine;
⎯ stopping the machine in an emergency;
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ISO 14121-1:2007(E)
⎯ recovery of operation from jam;
⎯ re-start after unscheduled stop;
⎯ faultfinding/trouble-shooting (operator intervention);
⎯ cleaning and housekeeping;
⎯ preventive maintenance;
⎯ corrective maintenance.
All reasonably foreseeable hazards, hazardous situations or hazardous events associated with the various
tasks shall then be identified. Annex A gives examples of hazards, hazardous situations and hazardous
events to assist in this process. Several methods are available for the systematic identification of hazards.
In addition, reasonably foreseeable hazards, hazardous situations or hazardous events not directly related to
tasks shall be identified (e.g. seismic events, lightning, excessive snow loads, noise, break-up of machinery,
hydraulic hose burst).
NOTE Examination of the available design documentation can be a useful means of identifying hazards on the
machinery, particularly those associated with moving elements (e.g. motors, hydraulic cylinders).
7 Risk estimation
7.1 General
After hazard identification (see Clause 6), risk estimation shall be carried out for each hazardous situation by
determining the elements of risk given in 7.2. When determining those elements, it is necessary to take into
account the aspects specified in 7.3.
7.2 Elements of risk
7.2.1 General
The risk associated with a particular hazardous situation depends on the following elements:
a) the severity of harm;
b) the probability of occurrence of that harm, which is a function of
1) the exposure of person(s) to the hazar
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