IEC GUIDE 127:2026

IEC GUIDE 127 ®
Edition 1.0 2026-02
GUIDE
Guidelines for safety-related risk assessment and risk reduction for
collaborative safety system
ICS 13.110 ISBN 978-2-8327-1049-4

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CONTENTS
FOREWORD . 2
INTRODUCTION . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Basic principles of collaborative safety . 7
4.1 General . 7
4.2 Principle of risk reduction in collaborative safety . 8
4.3 Safety consideration by characteristics of collaborative safety . 9
4.4 Risk reduction measures with collaborative safety consideration . 10
5 Aspects of risk . 12
Bibliography . 13

Figure 1 – Example of collaboration . 7
Figure 2 – Example of coexistence . 7
Figure 3 – Tripartite model for collaborative safety . 8
Figure 4 – Principle of risk reduction . 9
Figure 5 – Risk assessment and risk reduction flow chart considering collaborative
safety . 11

Table 1 – Examples of the risk associated with each element and related information to
be used . 12

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Guidelines for safety-related risk assessment
and risk reduction for collaborative safety system

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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IEC Guide 127 has been prepared, in accordance with ISO/IEC Directives, Part 1, Annex A, by
the IEC Advisory Committee on Safety (ACOS).
The text of this Guide is based on the following documents:
Draft Report on voting
SMBNC/81/DV SMBNC/87/RV
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Guide is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.

INTRODUCTION
Standardization deals with safety aspects in many different forms across a wide range of
technologies and for many products, processes, services and systems (referred to as "products
and systems" in this document). Products and systems are becoming more complex and must
be safeguarded accordingly. Furthermore, machine learning, autonomy and other technologies
that enable real-time human-machine collaboration and coexistence between humans and
autonomous machines should be considered as well.
This document provides practical guidance on drafting standards so as to include collaborative
safety aspects. The underlying principles of this document can also be used wherever
collaborative safety is considered, and as a useful reference for other stakeholders such as
designers, service providers, policy makers and regulators.
The approach described in this document is intended to establish risk assessment criteria for
the use of products and systems, including use by vulnerable people, when risks arising
individually from machine, human, and the environment change dynamically and independently
of each other, and thus to reduce risks as needed.
This document aims to reduce the risk arising from the design, production, distribution, use
(including maintenance) and destruction or disposal of products or systems. The complete life
cycle of a product or system (including both the intended use and the reasonably foreseeable
misuse) is considered, whether the product or system is intended to be used in a workplace, in
a household environment, or for recreational activities. The goal is to achieve tolerable risk for
people, property and the environment.
Additional topics and considerations are under study for the next revision of IEC Guide 127
such as different types of users (e.g. professional, unskilled, maintenance, and supervisor) and
categorization of risks.
1 Scope
This document provides recommendations on drafting standards so as to include safety aspects
where humans, machines, and the operational context mutually associate to mitigate risk by
providing protective measures in standards.
This document supplements ISO/IEC Guide 51 and IEC Guide 116 by specifying additional
recommendations relevant to collaborative safety-related aspects in standards.
This document supplements, in particular, the safeguarding and complementary protective
measures (Step 2) and can include protective measures taken by the user (e.g. provision and
use of additional safeguards), both illustrated in IEC Guide 116:2018, Figure 5.
This document is not applicable for the development of publications related to medical devices,
which is covered by ISO/IEC Guide 63 [1].
NOTE 1 The safety implications of a cybersecurity attack that has potential to cause harm to humans are included
in IEC Guide 116.
NOTE 2 The IEC Standardization Management Board (SMB) has decided that Guides such as this one can have
mandatory requirements which shall be followed by all IEC committees developing technical work that falls within the
scope of the Guide, as well as guidance which may or may not be followed. The mandatory requirements in this
Guide are identified by the use of "shall". Statements that are only for guidance are identified by using the verb
"should". (See ISO/IEC Directives, IEC Supplement:2021, A.1.1.)
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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/IEC Guide 51:2014, Safety aspects - Guidelines for their inclusion in standards
IEC Guide 116:2018, Guidelines for safety related risk assessment and risk reduction for low
voltage equipment
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC Guide 51,
IEC Guide 116 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.1
collaborative safety
state realized after risk reduction where humans (3.3), machines (3.4) and the operational
context (3.5) mutually associate to provide protective measures
Note 1 to entry: Collaborative safety consists of three essential elements: humans (3.3), machines (3.4) and
operational context (3.5).
Note 2 to entry: In application, collaborative safety is useful because the risks that fluctuate during operation are
mitigated so as to be maintained at tolerable levels.
Note 3 to entry: Collaborative safety can be achieved in coexistence (3.8), whether in collaboration (3.7) or not.
3.2
collaborative safety system
hardware or software or both establishing collaborative safety of a technical system, together
with a human, in the intended operational context (3.5)
Note 1 to entry: Collaborative safety aspects include, but are not limited to, hardware or software or bo
...