oSIST prEN ISO 3691-4:2026
(Main)Industrial trucks - Safety requirements and verification - Part 4: Driverless industrial trucks and their systems (ISO/DIS 3691-4:2026)
General Information
- Abstract
This document specifies safety requirements and the means for their verification for driverless industrial trucks (hereafter referred to as trucks) and their systems.
Examples of driverless industrial trucks (trucks as defined in ISO 5053‑1:2020) include: “automated guided vehicle”, “autonomous mobile robot”, “bots”, “automated guided cart”, “tunnel tugger”, “under cart”, etc.
This document is also applicable to driverless industrial trucks which are provided with:
— automatic modes which either require operators’ action(s) to initiate or enable such automatic operations;
— the capability to transport one or more riders (which are neither considered as drivers nor as operators);
— additional manual modes which allow operators to operate the truck manually; or
— a maintenance mode which allows manual operation of truck functions for maintenance reasons.
This document is not applicable to trucks solely guided by mechanical means (rails, guides, etc.) or to remotely-controlled trucks, which are not considered to be driverless trucks.
For the purposes of this document, a driverless industrial truck is a powered truck, which is designed to operate automatically. A driverless truck system comprises the control system, which can be part of the truck and/or separate from it, guidance means and power system. Requirements for power sources are not covered in this document.
The condition of the operating zone has a significant effect on the safe operation of the driverless industrial truck. The preparations of the operating zone to eliminate the associated hazards are specified in Annex A.
This document is applicable to all significant hazards, hazardous situations or hazardous events during all phases of the life of the truck (ISO 12100:2010, 5.4), as listed in Annex B, relevant to the applicable machines when it is used as intended and under conditions of misuse which are reasonably foreseeable by the manufacturer.
In particular, this document does not apply to significant hazards related to:
— noise;
— vibrations;
— ionising and non-ionising radiation;
— laser radiation;
— sales literature (commercial documents);
— declaration of vibrations transmitted by mobile machinery.
It does not apply to additional hazards that can occur:
— during operation in severe conditions (e.g. extreme climates, freezer applications, strong magnetic fields);
— during operation in nuclear environments;
— from trucks intended to operate in public zones (see in particular ISO 13482:2014);
— during operation on a public road;
— during operation in potentially explosive environments;
— during operation in military applications;
— during operation with specific hygienic requirements;
— during operation in ionizing radiation environments;
— during the transportation of (a) person(s) other than (the) intended rider(s);
— when handling loads the nature of which can lead to dangerous situations (e.g. molten metals, acids/bases, radiating materials);
— for rider positions with elevation function higher than 1 200 mm from the floor/ground to the platform floor.
This document does not contain safety requirements for trailer(s) being towed behind a truck.
This document does not contain safety requirements for elevated operator trucks.
This document does not apply to trucks manufactured before the date of its publication.
- Status
- Not Published
- Public Enquiry End Date
- 03-Sep-2026
- Technical Committee
- DTN - Lift and transport appliances
- Current Stage
- 4020 - Public enquire (PE) (Adopted Project)
- Start Date
- 24-Jun-2026
- Due Date
- 11-Nov-2026
Overview
oSIST prEN ISO 3691-4:2026 establishes internationally recognized safety requirements and methods of verification for driverless industrial trucks and their systems. This standard, developed by SIST and based on ISO/DIS 3691-4:2026, provides essential guidance for manufacturers, integrators, and users of automated guided vehicles (AGVs), autonomous mobile robots (AMRs), and similar driverless trucks operating in industrial environments.
The standard covers the safety considerations throughout the truck’s lifecycle, including design, operation, maintenance, and foreseeable misuse, ensuring safe interaction between driverless trucks and people in industrial settings. Certain vehicles, operations, and hazards are beyond the standard’s scope, with a focus specifically on the unique requirements of powered, automated industrial trucks.
Key Topics
Scope of Application
- Applies to driverless, powered industrial trucks including AGVs, AMRs, bots, automated guided carts, tunnel tuggers, and under carts, as defined in ISO 5053-1:2020.
- Covers trucks with additional manual, automatic, or maintenance modes, and those able to transport non-driver riders.
- Excludes trucks only guided by mechanical means (rails, guides); remotely controlled trucks; and operator-elevated or public-road vehicles.
Safety Requirements
- Emphasizes risk identification and reduction across all phases: design, installation, commissioning, operation, and service.
- Specifies safeguards for hazardous movements, load handling, and truck stability.
- Addresses detection of people and objects in the truck’s path, emergency stop functions, and safe control system design.
- Requires appropriate warning markings, signage, and operational information for safe use.
Verification and Testing
- Details means for verifying compliance through inspection, testing, and documentation.
- Includes procedures for validating person detection systems, stop functions, and truck stability.
- Annexes specify requirements for operational environments and methods for performance verification.
Information for Use
- Outlines essential instructions for the user, including operational manuals, maintenance procedures, and floor/ground condition requirements.
- Requires clear marking and warning systems on the truck and related documentation.
Exclusions and Limitations
- The standard does not address hazards from noise, vibration, ionising/non-ionising radiation, or military/nuclear environments.
- Not applicable to public road trucks, those designed for severe/extreme conditions, elevated operator platforms over 1,200 mm, and vehicles manufactured before publication.
Applications
oSIST prEN ISO 3691-4:2026 is critical for organizations designing, producing, or deploying driverless industrial trucks. Typical applications include:
- Warehouse automation and logistics: Ensuring AGVs and AMRs can operate safely around trained personnel and within designated zones.
- Manufacturing plants: Enabling integration of automated carts and robots for transporting materials, parts, and finished goods while minimizing incident risks.
- Distribution centers: Applying uniform safety protocols for fleets of automated and hybrid driverless vehicles.
- System integration: Providing a framework to assess, verify, and document safety compliance of new or upgraded driverless truck systems.
Related Standards
Organizations referencing oSIST prEN ISO 3691-4:2026 should consider its relationship to the following standards:
- ISO 5053-1:2020 - Industrial trucks - Vocabulary - Types of industrial trucks
- ISO/DIS 3691-1:2025 - Safety requirements for self-propelled industrial trucks (excluding driverless types)
- ISO 12100:2010 - Risk assessment and risk reduction for machinery safety
- ISO 13849-1:2023 - Safety-related parts of control systems - General principles
- ISO 13850:2015 - Emergency stop function - Design principles
Practical Value
Adoption of oSIST prEN ISO 3691-4:2026 helps organizations:
- Reduce workplace accidents involving automated and driverless industrial trucks.
- Streamline legal compliance and certification processes for new automated vehicle installations.
- Boost customer and workforce confidence in automated logistics operations.
- Promote interoperability and compatibility in multi-vendor automation environments.
By adhering to this standard, organizations can ensure their driverless industrial trucks are designed, verified, and operated with best-in-class safety provisions, creating more efficient and secure industrial logistics chains.
Relations
- Effective Date
- 13-Dec-2023
Frequently Asked Questions
oSIST prEN ISO 3691-4:2026 is a draft published by the Slovenian Institute for Standardization (SIST). Its full title is "Industrial trucks - Safety requirements and verification - Part 4: Driverless industrial trucks and their systems (ISO/DIS 3691-4:2026)". This standard covers: This document specifies safety requirements and the means for their verification for driverless industrial trucks (hereafter referred to as trucks) and their systems. Examples of driverless industrial trucks (trucks as defined in ISO 5053‑1:2020) include: “automated guided vehicle”, “autonomous mobile robot”, “bots”, “automated guided cart”, “tunnel tugger”, “under cart”, etc. This document is also applicable to driverless industrial trucks which are provided with: — automatic modes which either require operators’ action(s) to initiate or enable such automatic operations; — the capability to transport one or more riders (which are neither considered as drivers nor as operators); — additional manual modes which allow operators to operate the truck manually; or — a maintenance mode which allows manual operation of truck functions for maintenance reasons. This document is not applicable to trucks solely guided by mechanical means (rails, guides, etc.) or to remotely-controlled trucks, which are not considered to be driverless trucks. For the purposes of this document, a driverless industrial truck is a powered truck, which is designed to operate automatically. A driverless truck system comprises the control system, which can be part of the truck and/or separate from it, guidance means and power system. Requirements for power sources are not covered in this document. The condition of the operating zone has a significant effect on the safe operation of the driverless industrial truck. The preparations of the operating zone to eliminate the associated hazards are specified in Annex A. This document is applicable to all significant hazards, hazardous situations or hazardous events during all phases of the life of the truck (ISO 12100:2010, 5.4), as listed in Annex B, relevant to the applicable machines when it is used as intended and under conditions of misuse which are reasonably foreseeable by the manufacturer. In particular, this document does not apply to significant hazards related to: — noise; — vibrations; — ionising and non-ionising radiation; — laser radiation; — sales literature (commercial documents); — declaration of vibrations transmitted by mobile machinery. It does not apply to additional hazards that can occur: — during operation in severe conditions (e.g. extreme climates, freezer applications, strong magnetic fields); — during operation in nuclear environments; — from trucks intended to operate in public zones (see in particular ISO 13482:2014); — during operation on a public road; — during operation in potentially explosive environments; — during operation in military applications; — during operation with specific hygienic requirements; — during operation in ionizing radiation environments; — during the transportation of (a) person(s) other than (the) intended rider(s); — when handling loads the nature of which can lead to dangerous situations (e.g. molten metals, acids/bases, radiating materials); — for rider positions with elevation function higher than 1 200 mm from the floor/ground to the platform floor. This document does not contain safety requirements for trailer(s) being towed behind a truck. This document does not contain safety requirements for elevated operator trucks. This document does not apply to trucks manufactured before the date of its publication.
This document specifies safety requirements and the means for their verification for driverless industrial trucks (hereafter referred to as trucks) and their systems. Examples of driverless industrial trucks (trucks as defined in ISO 5053‑1:2020) include: “automated guided vehicle”, “autonomous mobile robot”, “bots”, “automated guided cart”, “tunnel tugger”, “under cart”, etc. This document is also applicable to driverless industrial trucks which are provided with: — automatic modes which either require operators’ action(s) to initiate or enable such automatic operations; — the capability to transport one or more riders (which are neither considered as drivers nor as operators); — additional manual modes which allow operators to operate the truck manually; or — a maintenance mode which allows manual operation of truck functions for maintenance reasons. This document is not applicable to trucks solely guided by mechanical means (rails, guides, etc.) or to remotely-controlled trucks, which are not considered to be driverless trucks. For the purposes of this document, a driverless industrial truck is a powered truck, which is designed to operate automatically. A driverless truck system comprises the control system, which can be part of the truck and/or separate from it, guidance means and power system. Requirements for power sources are not covered in this document. The condition of the operating zone has a significant effect on the safe operation of the driverless industrial truck. The preparations of the operating zone to eliminate the associated hazards are specified in Annex A. This document is applicable to all significant hazards, hazardous situations or hazardous events during all phases of the life of the truck (ISO 12100:2010, 5.4), as listed in Annex B, relevant to the applicable machines when it is used as intended and under conditions of misuse which are reasonably foreseeable by the manufacturer. In particular, this document does not apply to significant hazards related to: — noise; — vibrations; — ionising and non-ionising radiation; — laser radiation; — sales literature (commercial documents); — declaration of vibrations transmitted by mobile machinery. It does not apply to additional hazards that can occur: — during operation in severe conditions (e.g. extreme climates, freezer applications, strong magnetic fields); — during operation in nuclear environments; — from trucks intended to operate in public zones (see in particular ISO 13482:2014); — during operation on a public road; — during operation in potentially explosive environments; — during operation in military applications; — during operation with specific hygienic requirements; — during operation in ionizing radiation environments; — during the transportation of (a) person(s) other than (the) intended rider(s); — when handling loads the nature of which can lead to dangerous situations (e.g. molten metals, acids/bases, radiating materials); — for rider positions with elevation function higher than 1 200 mm from the floor/ground to the platform floor. This document does not contain safety requirements for trailer(s) being towed behind a truck. This document does not contain safety requirements for elevated operator trucks. This document does not apply to trucks manufactured before the date of its publication.
oSIST prEN ISO 3691-4:2026 is classified under the following ICS (International Classification for Standards) categories: 53.060 - Industrial trucks. The ICS classification helps identify the subject area and facilitates finding related standards.
oSIST prEN ISO 3691-4:2026 has the following relationships with other standards: It is inter standard links to SIST EN ISO 3691-4:2023. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
oSIST prEN ISO 3691-4:2026 is associated with the following European legislation: EU Directives/Regulations: 2023/1230, 2023/1230, 2023/1230, 2023/1230; Standardization Mandates: M/605. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
oSIST prEN ISO 3691-4:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-september-2026
Vozila za talni transport - Varnostne zahteve in preverjanje - 4. del: Vozila brez
voznika in njihovi sistemi (ISO/DIS 3691-4:2026)
Industrial trucks - Safety requirements and verification - Part 4: Driverless industrial
trucks and their systems (ISO/DIS 3691-4:2026)
Flurförderzeuge - Sicherheitstechnische Anforderungen und Verifizierung - Teil 4:
Fahrerlose Flurförderzeuge und ihre Systeme (ISO/DIS 3691-4:2026)
Chariots de manutention - Exigences de sécurité et vérification - Partie 4: Chariots de
manutention sans conducteur et leurs systèmes (ISO/DIS 3691-4:2026)
Ta slovenski standard je istoveten z: prEN ISO 3691-4
ICS:
53.060 Industrijski tovornjaki Industrial trucks
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
DRAFT
International
Standard
ISO/DIS 3691-4
ISO/TC 110/SC 2
Industrial trucks — Safety
Secretariat: SIS
requirements and verification —
Voting begins on:
Part 4: 2026-06-17
Driverless industrial trucks and
Voting terminates on:
2026-09-09
their systems
Chariots de manutention — Exigences de sécurité et
vérification —
Partie 4: Chariots sans conducteur et leurs systèmes
ICS: 53.060
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
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RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 3691-4:2026(en)
DRAFT
ISO/DIS 3691-4:2026(en)
International
Standard
ISO/DIS 3691-4
ISO/TC 110/SC 2
Industrial trucks — Safety
Secretariat: SIS
requirements and verification —
Voting begins on:
Part 4:
Driverless industrial trucks and
Voting terminates on:
their systems
Chariots de manutention — Exigences de sécurité et
vérification —
Partie 4: Chariots sans conducteur et leurs systèmes
ICS: 53.060
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
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Published in Switzerland Reference number
ISO/DIS 3691-4:2026(en)
ii
ISO/DIS 3691-4:2026(en)
Contents Page
Foreword .vi
Introduction .viii
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 5
4 Safety requirements and/or protective/risk reduction measures .11
4.1 General .11
4.1.1 Overall requirements .11
4.1.2 Normal climatic conditions . 12
4.1.3 Electrical requirements . 12
4.1.4 Electrostatic charges . 13
4.1.5 Stored energy components. 13
4.1.6 Edges or angles . 13
4.1.7 Guards . 13
4.1.8 Interlocking devices for guards . 13
4.1.9 Two-hand control devices .14
4.1.10 Transmission parts .14
4.1.11 Sensitive protective equipment (SPE) .14
4.1.12 Hydraulic systems .14
4.1.13 Pneumatic systems.14
4.1.14 Automatic restart .14
4.1.15 Foot protection . 15
4.1.16 Lifting and transport of the truck, attachments and truck parts .16
4.1.17 Requirements for trucks which can have riders or operators onboard .16
4.1.18 High temperatures .18
4.1.19 Exhaust emissions.18
4.1.20 Errors of fitting .18
4.1.21 Normal stop .18
4.1.22 Operational stop .19
4.2 Movement stop function with external interface .19
4.3 Truck holding function .19
4.4 Overspeed .19
4.5 Automatic battery charging . 20
4.6 Load handling . 20
4.7 Steering .21
4.8 Stability . 22
4.8.1 General . 22
4.8.2 Tilting platform stability test . 22
4.8.3 Stability requirements for trucks not covered by 4.8.2 . 23
4.9 Safeguarding and complementary protective measures. 23
4.9.1 Detection of persons in the path . 23
4.9.2 Critical edge . 28
4.9.3 Speed limitation requirements. 29
4.9.4 Additional stop function .31
4.9.5 Automatic restart after detection of persons .31
4.9.6 Emergency stop .32
4.10 Modes of operation . 33
4.10.1 General . 33
4.10.2 Automatic mode . 34
4.10.3 Manual mode . . 34
4.10.4 Maintenance mode . . . 36
4.11 Trucks intended to tow trailers . 36
4.11.1 General . 36
4.11.2 Mechanical requirements .37
iii
ISO/DIS 3691-4:2026(en)
4.11.3 Automatic towing and coupling devices .37
4.12 Trucks intended for confined zone .37
4.13 Trucks intended for use in VNA . 38
4.13.1 General . 38
4.13.2 Truck requirements for VNA applications fitted with impeding devices . 38
4.13.3 Trucks requirements for VNA applications in a restricted VNA zone . 39
4.14 Safety functions of the control system . 39
4.15 Electromagnetic immunity . 44
4.16 Attachments fitted to a truck . 44
4.16.1 General . 44
4.16.2 Conveyors fitted to a truck .45
4.16.3 Lifting tables . 46
4.17 Warning systems . 46
4.18 Loss of communication .47
5 Verification of the safety requirements and/or protective/risk reduction measures .47
5.1 General .47
5.2 Tests for detection of persons .47
5.2.1 Contact SPE.47
5.2.2 Non-contact SPE . 48
5.2.3 Routine verification . 54
5.3 Test for side detection . 54
5.4 Stability tests . 55
5.4.1 General . 55
5.4.2 Stability tests for trucks not covered by 4.8.2. . 55
5.5 Fitness for purpose . 55
5.5.1 General . 55
5.5.2 Structural tests . 56
5.5.3 Dynamic tests . 56
6 Information for use .57
6.1 General .57
6.2 Instruction handbook.57
6.2.1 General .57
6.2.2 Concerning the trucks and system .57
6.2.3 Operation of the trucks and system . 58
6.2.4 Routine service and maintenance of the trucks and system . 58
6.2.5 Operating information .59
6.2.6 Information for the application .59
6.2.7 Details for floor/ground conditions . 60
6.2.8 Details for power sources . . 60
6.2.9 Truck modification . 60
6.3 Minimum marking . . 60
6.3.1 Marking . . 60
6.3.2 Warning signs for trucks .61
6.3.3 Information plates .62
6.4 Putting into service (commissioning) . 63
Annex A (normative) Requirements for the integration of truck(s) .64
Annex B (informative) List of significant hazards .86
Annex C (normative) Determination of rated capacity for truck with masts .91
Annex D (informative) Load transfer operations .93
Annex E (normative) Verification of the safety requirements and/or protective/risk reduction
measures .96
Annex F (informative) Specification of warning and indicator signals .117
Annex G (informative) Cross reference with industrial truck types of ISO 5053-1 .122
iv
ISO/DIS 3691-4:2026(en)
Annex H (normative) Requirements for the implementation of muting by a combination of truck
signals . . .125
Annex I (normative) Determination of alternative performance levels for safety functions .127
Annex J (normative) Alternative method to demonstrate Performance Level b (PL b) for
clearance management based on Localization Systems. . 128
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Regulation (EU) 2023/1230 aimed to be covered .131
Bibliography .135
v
ISO/DIS 3691-4:2026(en)
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.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 110, Industrial trucks, Subcommittee SC 2,
Safety of powered industrial trucks, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 150, Industrial Trucks - Safety, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of this
document.
This third edition cancels and replaces the second edition (ISO 3691-4:2023), which has been technically
revised.
The main changes are as follows:
— the Scope has been updated to include:
a) a list of types of trucks not covered;
b) a reference to the operating environment as defined in Annex A;
c) a list of significant hazards not covered;
d) the exclusion of domestic animals;
— the list of normative references has been updated to include the most recent editions of documents;
— the term entries have been updated and additional term entries, added in Clause 3;
— 4.9 integrates changes for detection of persons and safeguarding;
— 5.2 has been updated to include new test pieces dependant on Non-contact SPE;
vi
ISO/DIS 3691-4:2026(en)
— 5.3 includes additional testing for side detection;
— Annex A now includes all the specific content required for the commissioning phase of the installation;
— Annex F has been added for specification of warning and indicator signals;
— Annex G has been added for cross reference with industrial truck types of ISO 5053-1;
— Annex H has been added for implementation of muting by a combination of trucks signals;
— Annex I has been added for determination of alternative performance levels for safety functions;
— Annex J has been added for demonstration with an alternative method of a PL b for clearance management
based on localisation systems.
A list of all parts in the ISO 3691 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
vii
ISO/DIS 3691-4:2026(en)
Introduction
This document is a type-C standard as stated in ISO 12100:2010.
This document is of relevance, in particular, for the following stakeholder groups representing the market
players with regard to machinery safety:
— machine manufacturers (small, medium and large enterprises);
— health and safety bodies (regulators, accident prevention organizations, market surveillance, etc.).
Others can be affected by the level of machinery safety achieved with the means of the document by the
above-mentioned stakeholder groups:
— machine users/employers (small, medium and large enterprises);
— machine users/employees (e.g. trade unions, organizations for people with special needs);
— service providers, e.g. for maintenance (small, medium and large enterprises);
— consumers (in case of machinery intended for use by consumers).
The above-mentioned stakeholder groups have been given the possibility to participate at the drafting
process of this document.
The machinery concerned and the extent to which hazards, hazardous situations or hazardous events are
covered are indicated in the Scope of this document. This document covers driverless industrial trucks and
their systems.
When requirements of this type-C standard are different from those which are stated in type-A or type-B
standards, the requirements of this type-C standard take precedence over the requirements of the other
standards for machines that have been designed and built according to the requirements of this type-C
standard.
This document takes into consideration the current state of the art and especially:
— non-contact sensitive protective equipment technology;
— hybrid operated trucks (i.e. manual and automatic operation);
— updates to clearances;
— additional safety functions (e.g. side detection, critical edge detection);
— safeguarding for specific zones.
viii
DRAFT International Standard ISO/DIS 3691-4:2026(en)
Industrial trucks — Safety requirements and verification —
Part 4:
Driverless industrial trucks and their systems
1 Scope
This document specifies safety requirements and the means for their verification for driverless industrial
trucks (hereafter referred as trucks) and their systems.
NOTE 1 Examples of industrial trucks can be found in ISO 5053-1:2020
For the purpose of this document, driverless industrial trucks are:
— powered mobile machines;
— having at least three wheels;
— operating in an industrial environment;
— designed to carry, tow, push, lift, tier in a rack, or stack a load (load handling);
— controlled by automation, independent of their level of autonomy and;
— which remain stable in the absence of power.
NOTE 2 Level of autonomy is to be understood as type of navigation.
This document is also applicable to trucks which are provided with one or more of the following:
— automatic modes which either require operators’ actions to initiate or enable such automatic operations;
— the capability to transport one or more riders (which are not considered as drivers);
— additional modes which allow operators to operate the truck manually;
— maintenance modes which allow manual operation of truck functions for maintenance reasons.
This document is applicable where trucks operate in an area of application where people have specific
training, instruction or awareness.
This document is applicable to all significant hazards, hazardous situations or hazardous events during all
phases of the lifecycle (ISO 12100:2010, 5.4), as listed in Annex B, relevant to the applicable machines when
they are used as intended and under conditions of misuse which are reasonably foreseeable. This document
is not applicable to the following:
— solely mechanically guided trucks;
— trucks that are solely remotely controlled by an operator (see ISO/DIS 3691-1:2025).
This document does not cover significant hazards related to:
— protection against corruption;
— special requirements for guards / adjustable guards restricting access;
— noise;
ISO/DIS 3691-4:2026(en)
— vibrations;
— ionising and non-ionising radiation;
— laser radiation;
— cleaning of internal parts;
— sales literature (commercial documents);
— supervisory function;
— declaration of vibrations transmitted by mobile machinery;
— self-evolving behaviour or logic (e.g, artificial intelligence).
It does not address the hazards that can occur:
— during operation in severe conditions (e.g. extreme climates, freezer applications, strong magnetic
fields);
— during operation in nuclear environments;
— during operation on a public road;
— during operation in potentially explosive environments;
— during operation in military applications;
— during operation with specific hygienic requirements;
— during operation in ionizing radiation environments;
— during the transportation of (a) person(s) other than (the) intended rider(s);
— when handling loads the nature of which can lead to dangerous situations (e.g. molten metals, acids/
bases, radiating materials);
— for rider positions with an elevation function higher than 1 200 mm from the floor/ground to the platform
floor.
This document does not contain safety requirements for trucks intended to operate in public zones or spaces
accessible to any persons without specific training, instruction or awareness.
This document does not contain safety requirements for trailer(s) being towed behind a truck.
This document does not contain specific safety requirements for elevated operator trucks.
This document does not apply to trucks manufactured before the date of its publication.
This document does not take into consideration domestic animals as they are not expected to be present in
industrial environments.
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 2867:2011, Earth-moving machinery — Access systems
ISO/DIS 3691-1:2025, Industrial trucks — Safety requirements and verification — Part 1: Self-propelled
industrial trucks, other than driverless trucks, variable-reach trucks and burden-carrier trucks
ISO/DIS 3691-4:2026(en)
ISO 3691-2:2023, Industrial trucks — Safety requirements and verification — Part 2: Self-propelled variable-
reach trucks
ISO 3691-6:2021, Industrial trucks — Safety requirements and verification — Part 6: Burden and personnel
carriers
ISO 4413:2010, Hydraulic fluid power — General rules and safety requirements for systems and their components
ISO 4414:2010, Pneumatic fluid power — General rules and safety requirements for systems and their
components
ISO 5053-1:2020, Industrial trucks — Vocabulary — Part 1: Types of industrial trucks
1)
ISO 7010:2019 , Graphical symbols — Safety colours and safety signs — Registered safety signs
ISO 7250-1:2017, Basic human body measurements for technological design — Part 1: Body measurement
definitions and landmarks
ISO 10896-1:2020, Rough-terrain trucks — Safety requirements and verification — Part 1: Variable-reach
trucks
ISO 10896-2:2016, Rough-terrain trucks — Safety requirements and verification — Part 2: Slewing trucks
ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk reduction
ISO 13849-1:2023, Safety of machinery — Safety-related parts of control systems — Part 1: General principles
for design
ISO 13849-2:2012, Safety of machinery — Safety-related parts of control systems — Part 2: Validation
ISO 13850:2015, Safety of machinery — Emergency stop function — Principles for design
ISO 13851:2019, Safety of machinery — Two-hand control devices — Principles for design and selection
ISO 13855:2024, Safety of machinery — Positioning of safeguards with respect to the approach of the human
body
ISO 13856-2:2013, Safety of machinery — Pressure-sensitive protective devices — Part 2: General principles for
design and testing of pressure-sensitive edges and pressure-sensitive bars
ISO 13856-3:2013, Safety of machinery — Pressure-sensitive protective devices — Part 3: General principles for
design and testing of pressure-sensitive bumpers, plates, wires and similar devices
ISO 13857:2019, Safety of machinery — Safety distances to prevent hazard zones being reached by upper and
lower limbs
ISO 14119:2024, Safety of machinery — Interlocking devices associated with guards — Principles for design and
selection
ISO 14120:2015, Safety of machinery — Guards — General requirements for the design and construction of fixed
and movable guards
ISO 14122-2:2016, Safety of machinery — Permanent means of access to machinery — Part 2: Working platforms
and walkways
ISO 15870:2000, Powered industrial trucks — Safety signs and hazard pictorials — General principles
ISO 22915-2:2018, Industrial trucks — Verification of stability — Part 2: Counterbalanced trucks with mast
ISO 22915-3:2021, Industrial trucks — Verification of stability — Part 3: Reach and straddle trucks
1) As impacted by ISO 7010:2019/Amd 1:2020, ISO 7010:2019/Amd 2:2020, ISO 7010:2019/Amd 3:2021,
ISO 7010:2019/Amd 4:2021, ISO 7010:2019/Amd 5:2022,ISO 7010:2019/Amd 6:2022, ISO 7010:2019/Amd 7:2023,
ISO 7010:2019/Amd 8:2024, ISO 7010:2019/Amd 9:2025 and ISO 7010:2019/Amd 10:2025.
ISO/DIS 3691-4:2026(en)
ISO 22915-4:2018, Industrial trucks — Verification of stability — Part 4: Pallet stackers, double stackers and
order-picking trucks with operator position elevating up to and including 1 200 mm lift height
ISO 22915-5:2020, Industrial trucks — Verification of stability — Part 5: Single-side-loading trucks
ISO 22915-7:2016, Industrial trucks — Verification of stability — Part 7: Bidirectional and multidirectional
trucks
ISO 22915-8:2026, Industrial trucks — Verification of stability — Part 8: Additional stability test for trucks
operating in the special condition of stacking with mast tilted forward and load elevated
ISO 22915-9:2014, Industrial trucks — Verification of stability — Part 9: Counterbalanced trucks with mast
handling freight containers of 6 m (20 ft) length and longer
ISO 22915-10:2023, Industrial trucks — Verification of stability — Part 10: Additional stability test for trucks
operating in the special condition of stacking with load laterally displaced by powered devices
ISO 22915-11:2011, Industrial trucks — Verification of stability — Part 11: Industrial variable-reach trucks
ISO 22915-12:2015, Industrial trucks — Verification of stability — Part 12: Industrial variable-reach trucks
handling freight containers of 6 m (20 ft) length and longer
ISO 22915-13:2026, Industrial trucks — Verification of stability — Part 13: Rough-terrain trucks with mast
ISO 22915-14:2010, Industrial trucks — Verification of stability — Part 14: Rough-terrain variable-reach trucks
ISO 22915-15:2020, Industrial trucks — Verification of stability — Part 15: Counterbalanced trucks with
articulated steering
ISO 22915-17:2020, Industrial trucks — Verification of stability — Part 17: Towing tractors, burden and
personnel carriers
ISO 22915-20:2023, Industrial trucks — Verification of stability — Part 20: Additional stability test for trucks
operating in the special condition of offset load, offset by utilization
ISO 22915-22:2014, Industrial trucks — Verification of stability — Part 22: Lateral- and front-stacking trucks
with and without elevating operator position
IEC 61496-1:2020, Safety of machinery - Electro-sensitive protective equipment - Part 1: General requirements
and tests
IEC 61496-2:2020, Safety of Machinery — Electro-sensitive protective equipment — Part 2: Particular
requirements for equipment using active opto-electronic protective devices (AOPDs)
IEC 61496-3:2025, Safety of machinery —Electro-sensitive protective equipment — Part 3: Particular
requirements for Active Opto-electronic Protective Devices responsive to Diffuse Reflection (AOPDDR)
I EC 6 020 4 -1:2016 +A M D1: 2021, Safety of machinery — Electrical equipment of machines — Part 1: General
requirements
IEC 61558-1:2017, Safety of power transformers, power supply units, reactors and similar — Part 1: General
requirements and tests
IEC FDIS/62046:2026, Safety of machinery - Application of protective equipment to detect the presence of
persons
EN 619:2022, Continuous handling equipment and systems - Safety requirements for equipment for mechanical
handling of unit loads
EN 1175:2025, Safety of industrial trucks — Electrical/electronic requirements
EN 1570-1:2024, Safety requirements for lifting tables - Part 1: Lifting tables serving up to two fixed landing
E N 128 95:2015+A 1: 2019, Industrial trucks — Electromagnetic compatibility
ISO/DIS 3691-4:2026(en)
EN 16307-1:2020, Industrial trucks - Safety requirements and verification - Part 1: Supplementary requirements
for self propelled industrial trucks, other than driverless trucks, variable-reach trucks and burden-carrier trucks
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5053-1:2020, ISO 5053-2:2019,
ISO 5053-3:2024 and ISO 12100:2010 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:
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