ISO 13649:2024

International
Standard
ISO 13649
First edition
Earth-moving machinery — Fire
2024-09
prevention guidance
Engins de terrassement — Lignes directrices pour la prévention
des incendies
Reference number
© ISO 2024
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Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Fire hazards . 2
4.1 General .2
4.2 Fuel sources .3
4.2.1 General .3
4.2.2 Machine components .3
4.2.3 Machine fluids, gases and other onboard substances .3
4.2.4 Environmental debris .3
4.3 Oxidizers .3
4.4 Ignition sources .3
4.4.1 General .3
4.4.2 Thermal energy ignition sources.4
4.4.3 Electrical energy ignition sources .4
4.4.4 Mechanical energy ignition sources .4
5 Strategy for risk assessment and risk reduction . 4
6 Design guidance for fire risk reduction . 5
6.1 General .5
6.2 Ignition sources .5
6.2.1 Mechanical and thermal ignition sources .5
6.2.2 Electrical ignition sources .5
6.3 Fuel sources .6
6.4 Segregation of fuel and ignition sources .7
6.5 Fire extinguishers and fire suppression .8
7 Information for use . 8
7.1 General .8
7.2 Fire prevention .8
7.2.1 Operation .8
7.2.2 Fuelling .9
7.2.3 Starting .9
7.2.4 Maintenance and inspection .9
7.2.5 Service and repair .11
7.3 Fire safety .11
Annex A (informative) Examples of fuel sources .13
Annex B (informative) Examples of ignition sources .15
Bibliography . 17

iii
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,
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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 document 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
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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 127, Earth-moving machinery, Subcommittee
SC 2, Safety, ergonomics and general requirements.
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.

iv
International Standard ISO 13649:2024(en)
Earth-moving machinery — Fire prevention guidance
1 Scope
This document provides guidance on protective measures for consideration in fire risk reduction through
machine design and operation and maintenance instructions for earth-moving machinery, as defined in
ISO 6165, during their intended use.
NOTE The information in this document presumes that fire hazards for the normal applications anticipated for the
machine family by the machine manufacturer have been analysed. This analysis can be done as part of the ISO 12100
machine risk assessment or as a separate fire hazard risk assessment conducted in accordance with ISO 12100 or
ISO 19353:2019, 5.1, 5.2, 5.3 and 5.4.
This document also provides the basic concept of fire hazards and examples of typical fuel sources and
ignition sources found in earth-moving machinery and earth-moving machinery applications.
This document does not cover all specific aspects of fire prevention for battery electric powertrains (e.g. fire
prevention for batteries, battery management systems) due to the evolving development of such technology.
However, the guidance in this document can still be beneficial. Additional guidance can also be found in the
1)
ISO 14990 series and ISO/DIS 23285.
This document does not cover the additional risks for machines operating in potentially explosive
atmospheres.
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 12100, Safety of machinery — General principles for design — Risk assessment and risk reduction
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12100, 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:// www .electropedia .org/
3.1
explosive atmosphere
atmospheres containing substances or gases at concentrations that will burn or explode if ignited
[SOURCE: ISO/TR 19591:2018, 3.112]
3.2
fire prevention
measures to prevent the outbreak of a fire and/or to limit its effects
[SOURCE: ISO 8421-1:1987, 1.21]
1)  Under preparation. Stage at the time of publication: ISO/DIS 23285:2024

3.3
ignition energy
energy necessary to initiate combustion
[SOURCE: ISO 19353:2019, 3.8]
3.4
ignition source
source of energy that initiates combustion
[SOURCE: ISO 13943:2023, 3.244]
3.5
combustible
capable of burning
[SOURCE: ISO 8421-1:1987, 1.9]
3.6
firewall
wall or partition designed to inhibit or prevent the spread of fire
4 Fire hazards
4.1 General
A fire hazard exists if combustible materials (fuel), oxidizer (oxygen) and ignition energy (heat) are
available in sufficient quantities at the same place and at the same time. A fire is an interaction of these three
components in the form of an uninhibited chemical chain reaction. See Figure 1.
Key
1 heat (see 4.3)
2 oxygen
3 fuel (see 4.2)
4 uninhibited chemical chain reaction
Figure 1 — Fire tetrahedron
A fire can be prevented or suppressed by controlling or removing one or more of the components of the fire
tetrahedron.
4.2 Fuel sources
4.2.1 General
Fuel is any substance that can undergo combustion. Fuel sources can occur as solids, liquids or gases. Fuel
sources can arise from the material processed, used or released by the machinery, from materials in the
vicinity of the machinery, or from materials used in the construction of the machinery.
The ease of combustion of fuel sources is affected by the size, shape and deposition of the materials. For
example, small pieces of a material loosely collected together can be more easily ignited than a large piece
of that material. Also, the combination of materials can have an influence on the ignitability and the burning
behaviour. Where relevant properties of fuel sources are not well understood, appropriate testing or analysis
should be conducted.
4.2.2 Machine components
Materials used in the construction of machine components can be fuel sources. See Annex A for examples of
machine components that can be fuel sources for earth-moving machinery.
4.2.3 Machine fluids, gases and other onboard substances
Fluids, gases and other onboard substances required for operation of the machine can be a fuel source.
Leaks, spills and overflows of these fluids or gases can become the fuel source for a fire. See Annex A for
examples of machine fluids, gases and other onboard substances that can be fuel sources for earth-moving
machinery.
4.2.4 Environmental debris
Combustible materials from the working environment which accumulate on or in the machine can be a
fuel source. The amount of accumulation can be affected by weather conditions, type of debris, machine
design, missing machine components, operational and maintenance practices, and other factors. The ease of
combustion of these materials is affected by the size, shape, and deposition of the materials. See Annex A for
examples of environmental debris that can be fuel sources for earth-moving machinery.
4.3 Oxidizers
An oxidizing agent is a chemical substance that, while not necessarily combustible by itself, can rapidly
increase the rate of burning of other substances, or result in spontaneous combustion when combined with
other substances. The most common oxidizer is oxygen in the atmosphere. But there are other oxidizers that
support combustion, e.g. ammonium nitrate (NH NO ) and potassium nitrate (KNO ).
4 3 3
4.4 Ignition sources
4.4.1 General
Ignition sources for an onboard fire typically fall into three categories:
— thermal energy;
— electrical energy;
— mechanical energy.
These ignition sources can come from the machine itself and from sources external to the machine.

4.4.2 Thermal energy ignition sources
Thermal energy is the energy contained within a system that is responsible for its temperature. The transfer
of heat from these systems can be a thermal energy ignition source. See Annex B for examples of thermal
energy ignition sources for earth-moving machinery.
4.4.3 Electrical energy ignition sources
Electrical energy is the movement of electrons from one point to another. Heat created by unconstrained
movement of electrons can be an electrical energy ignition source. See Annex B for examples of electrical
energy ignition sources for earth-moving machinery.
4.4.4 Mechanical energy ignition sources
Mechanical energy is the energy created by friction of one component moving over another. The heat created
by this friction can be a mechanical energy ignition source. See Annex B for examples of mechanical energy
ignition sources for earth-moving machinery.
5 Strategy for risk assessment and risk reduction
The risk assessment and risk reduction process for fire prevention comprises a series of logical steps that
allow systematic examination of fire hazards according to the procedures outlined in ISO 12100. This
process includes the following sequential phases:
a) fire risk analysis, comprising:
1) determination of the limits of the machinery;
2) identification of fire hazards;
NOTE Machine and application incident history can be used as sources of information to help identify fire
hazards.
3) risk estimation;
b) risk evaluation;
c) risk reduction, if deemed necessary.
If risk reduction is required, then appropriate protective measures should be selected and applied. Clause 6
provides design guidance for fire risk reduction specific to earth-moving machinery.
The risk assessment and risk reduction process for machinery should consider the entire lifecycle of the
machine, including the following:
1) design, including but not limited to, the following:
— operator egress;
— considerations for fire suppression system;
— access ports for firefighting to fire risk areas on the machine (e.g. engine compartment).
2) installation, assembly, and commissioning;
3) operation;
4) maintenance;
5) decommissioning and dismantling.

The fire risk assessment and risk reduction is repeated as an iterative process until the risk of a fire
occurrence has been adequately reduced.
Care should be taken to ensure that the protective measures applied do not create or increase other risks.
See ISO 12100 or ISO 19353 for guidance on the risk assessment and risk reduction process.
Special use or severe applications (e.g. transporting hot materials) can require a separate risk assessment by
the site management specific to that machine application.
6 Design guidance for fire risk reduction
6.1 General
Design measures for eliminating or reducing the potential risk of fire should include consideration for
ignition sources, fuel sources, segregation of fuel and ignition sources, and minimizing the effects of fire.
6.2 Ignition sources
6.2.1 Mechanical and thermal ignition sources
Design considerations for mechanical or thermal ignition sources should include, but not be limited to, the
following:
a) Eliminate or minimize, as practical, exposed hot surfaces, for example:
— reduce surface temperatures with airflow;
— insulate or double-wall exhaust components;
— liquid cool components.
b) Eliminate or minimize, as practical, the risk of overheating of machine components and systems (e.g.
engines, transmissions, brakes, hydraulic systems, retarding grids, electrical motors). Where the
potential exists for overheating in the presence of a fuel source; either monitoring or controls, or both,
should be considered.
Simulation or surface temperature measurement can be carried out to understand machine surface
temperatures.
NOTE Surfaces above 250 °C are generally considered to support a higher likelihood of combustion with typical
fuel sources (e.g. diesel fuel, hydraulic oil) on board earth-moving machinery.
6.2.2 Electrical ignition sources
Design considerations for electrical ignition sources should include, but not be limited to, the following:
a) Eliminate or minimize, as practical, the risk of incorrect electrical connections. Electrical wires and
cables used to connect components in electric circuits should be marked and identified. ISO 9247,
ISO 23285 or ISO 14990-1 can be used as guidance.
b) Ensure electrical wires and cables, including wire and cable covering, are applicable for the intended
application. Considerations should include voltage, load, temperature, chemical resistance, contaminant
ingress (e.g. moisture, dust) and flammability rating.
c) Eliminate or minimize, as practical, the risk of overloading electrical circuits. Electrical circuits should
be protected by fuses, circuit breakers, or current limiting devices unless specifically designed to be
unprotected (e.g. starter motor, pre-heater). The circuit protection for the electrical equipment should
be as close as practical to the source. Protection devices should be sized to protect the conductors.
If a harness is split (separated into multiple wires), then the protection device should also be placed

immediately after the point of the split, unless protection device amperage rating prior to the split is
sufficiently low to protect the wire sizes after the split.
d) Eliminate or minimize, as practical, the risk of electrical shorting. Electrical wiring and cables should:
1) be routed and supported or clamped in a manner to prevent chafing, crushing or rubbing on sharp
edges or rough surfaces and to minimize damage from vibration. Reusable or permanent clamps are
preferred to assure proper support and routing are followed and repeatable after repairs. If cable
ties are used, consideration sho
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