ISO 22578:2025

International
Standard
ISO 22578
Second edition
Graphical symbols — Safety colours
2025-10
and safety signs — Natural disaster
safety way guidance system
Symboles graphiques — Couleurs de sécurité et signaux de
sécurité — Système de guidage pour mise en sécurité en cas de
catastrophe naturelle
Reference number
© ISO 2025
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Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Purpose and deployment . 3
5 Planning natural disaster safety way guidance systems . 3
6 Signs used in natural disaster safety way guidance systems . 3
6.1 Signs .3
6.2 Supplementary direction arrow signs . .5
6.3 Supplementary symbols and suitability marking .6
7 Structure of a natural disaster safety way guidance system . 7
7.1 Overview of structure . .7
7.2 Warning signs . .8
7.3 Evacuation plan signs .9
7.4 Evacuation route signs .10
7.5 Place of refuge signs . 13
8 Bilingual signs . 14
9 Identifiability and legibility of signs under daylight and night-time conditions .15
10 Installation of natural disaster safety way guidance systems .16
10.1 General .16
10.2 Sign positioning .16
10.3 Durability .17
11 Repair, maintenance and inspection . 17
Annex A (informative) Examples of installations of natural disaster safety way guidance
systems .18
Annex B (informative) Distance factors and sizing visual elements .26
Annex C (informative) Daylight and night-time illumination conditions .30
Annex D (normative) Measurement of photopic luminance of phosphorescent components
used in a natural disaster safety way guidance system.31
Bibliography .35

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,
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 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
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 145, Graphical symbols, Subcommittee SC 2,
Safety identification, signs, shapes, symbols and colours.
This second edition cancels and replaces the first edition (ISO 22578:2022) and ISO-22578-2:2024, which
have been technically revised.
The main changes are as follows:
— ISO 22578-2 has been incorporated as Annex D.
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
Introduction
There is a need to standardize a system for giving safety information related to evacuation to safety
evacuation areas in the event of natural disasters that relies as little as possible on the use of words to
achieve understanding.
It is extremely important for people who do not understand the local language to figure out the evacuation
route instantly when they encounter a natural disaster in a foreign country.
This document reflects best practice; the illustrations show installation practice designed to provide the
optimum amount of information to clearly identify the hazards of different types of natural disaster in order
to direct evacuation by the appropriate location of evacuation route signs and evacuation plan signs, and the
selection of places of refuge.
International travel increases the need for standardized methods of safety communication. A standardized
method of signing with the use of appropriate supplementary signs and text throughout the public
environment assists the process of education and instruction on the meaning of the evacuation route signs
and place of refuge signs, and the appropriate actions to take.
The illustrations within this document are based on the assumption that people might be unfamiliar with
the features of the natural disaster or the location of places of refuge.
It is important that the application of safety way guidance systems is standardized to aid comprehension.
While education in the comprehension of the signs and evacuation plan signs is essential, incomprehension
caused by lack of standardization can lead to confusion and possibly hinder effective evacuation.
This document does not purport to include all the necessary aspects or requirements of the design of a
natural disaster safety way guidance system. Users are responsible for its correct application.

v
International Standard ISO 22578:2025(en)
Graphical symbols — Safety colours and safety signs —
Natural disaster safety way guidance system
IMPORTANT — The colours represented in the electronic file of this document can be neither viewed
on screen nor printed as true representations. For the purposes of colour matching see ISO 3864-4,
which provides colorimetric and photometric properties together with, as a guideline, references
from colour order systems.
1 Scope
This document specifies the principles governing the design and application of signs and plans used to create
a natural disaster safety way guidance system to help people evacuate to safe areas or places of refuge in
case of natural disasters (e.g. tsunamis, floods, debris flows, steep slope failures, landslides, tornados, large-
scale fires, active volcanoes).
This document provides guidance on the selection and use of safety signs conforming to ISO 7010, public
information symbols conforming to ISO 7001, and text on evacuation route signs, places of refuge signs and
evacuation plan signs for information related to one or more particular natural disasters. Guidance on the
design, location, mounting positions and maintenance of the sign components of a natural disaster safety
way guidance system is also provided.
This document does not apply to the determination of the need for natural disaster safety way guidance.
This document assumes that the risk assessment or requirements of an enforcing authority have established
the need for such natural disaster safety way guidance systems.
This document is not applicable to the particular hazards of high winds, snow avalanches, earthquakes or
hurricanes, which cause the natural disasters covered in this document.
This document is applicable to safety way guidance from natural disasters from the outside of buildings to
safe areas. ISO 16069 is applicable to safety way guidance within a building to the emergency exit(s).
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 3864-1, Graphical symbols — Safety colours and safety signs — Part 1: Design principles for safety signs and
safety markings
ISO 3864-3, Graphical symbols — Safety colours and safety signs — Part 3: Design principles for graphical
symbols for use in safety signs
ISO 3864-4, Graphical symbols — Safety colours and safety signs — Part 4: Colorimetric and photometric
properties of safety sign materials
1)
ISO 7010 , Graphical symbols — Safety colours and safety signs — Registered safety signs
1)
ISO 16069 , Graphical symbols — Safety signs — Safety way guidance systems (SWGS)
ISO/CIE 19476, Characterization of the performance of illuminance meters and luminance meters
1) The graphical symbol collections of ISO 7010 and ISO 16069 can be previewed and purchased on the Online Browsing
Platform (OBP), www .iso .org/ obp.

3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
evacuation plan
map or diagram displayed in public areas to assist users to understand the environment, locate facilities and
determine evacuation routes to reach a safe area
3.2
evacuation route
direction from a person's location to the nearest safe area when a disaster occurs
3.3
natural disaster safety way guidance system
system that includes evacuation plan (3.1) signs and evacuation route (3.2) signs, and provides information
to guide people from a location to a place of refuge when a natural disaster occurs
3.4
natural disaster supplementary sign
sign indicating the type of possible disaster
Note 1 to entry: Appropriate evacuation area and other related information are also displayed.
3.5
ordinary material
material which is not retroreflecting, fluorescent or phosphorescent, and neither involves powered light
emission nor is activated by a radioactive source
[SOURCE: ISO 3864-4:2011, 3.11, modified — rearranged “neither” and “nor” for better understanding.]
3.6
phosphorescent material
material incorporating phosphors that, if excited by UV or visible radiation, store energy, which is emitted
as light over a period of time
Note 1 to entry: A phosphorescent sign is the same as “photoluminescent”, commonly used in the literature of the
photoluminescent safety sign industry.
[SOURCE: ISO 16069:2017, 3.15]
3.7
place of refuge
outdoor area or indoor space to which people can quickly evacuate in order to remain safe when a disaster
occurs or is likely to occur
Note 1 to entry: Places of refuge include protection shelters (3.8), outdoor refuge areas, tsunami evacuation areas and
tsunami evacuation buildings.
3.8
protection shelter
facility that provides protection from a disaster

3.9
sign height
diameter of a circular geometric shape or height of a rectangular or triangular geometric shape of the type
of safety sign
Note 1 to entry: Registered safety sign originals in ISO 7010 are in a uniform 70 mm size with corner marks to enable
accurate enlargement and reduction scaling. A border is not shown.
[SOURCE: ISO 20712-3:2020, 3.8, modified — Note 1 to entry revised.]
4 Purpose and deployment
The natural disaster safety way guidance system is necessary to warn people in areas likely to be affected
by a disaster when it occurs and help them take suitable action quickly according to the type of disaster.
The objective of the natural disaster safety way guidance system is to display information about the hazards
of possible natural disasters in vulnerable regions so both visitors and people living in the region can
evacuate quickly.
5 Planning natural disaster safety way guidance systems
Where risk mitigation plans related to natural disasters have been prepared and are available to civil
protection agencies or relevant authorities, a natural disaster safety way guidance system can be designed
to communicate important safety and evacuation information to populations in zones that can be affected
by one or more types of natural disaster.
The designer of the system should identify the following, based on the mitigation plans:
a) locations of hazard zones;
b) locations of places of refuge and their names;
c) suitability of places of refuge for certain disasters;
d) locations of evacuation routes to places of refuge;
e) locations of accessible routes in the event of floods from inland waters and fire disasters;
f) locations of rescue facilities (e.g. medical, firefighting);
g) locations of facilities for enabling emergency evacuation (e.g. helicopters, lifeboats);
h) locations of emergency communication equipment;
i) locations of available emergency services, such as water and energy supply;
j) appropriate supplementary text on evacuation route signs, such as information on recorded heights of
water at locations within flood zones;
k) use of local language(s) and other languages;
l) other sources of warning information, such as national and local media, and sound alarms.
6 Signs used in natural disaster safety way guidance systems
6.1 Signs
The safety sign components of natural disaster safety way guidance signs shall be registered safety
signs from ISO 7010. Supplementary signs and combination signs shall meet the design requirements of
ISO 3864-1. Signs used in natural disaster safety way guidance systems are shown in Table 1.

Safety signs shall be based on ordinary material or phosphorescent material. Safety signs shall meet the
colorimetric and photometric specifications of ISO 3864-4 under the test conditions relating to safety signs
being externally illuminated.
NOTE ISO 3864-4 defines colour under certain test conditions and not all conditions of observation of safety
signs. Phosphorescent safety signs during luminance decay mode lack colour recognition of the green; however, they
are designed such that the luminance contrast enables the graphical symbols to be or remain identifiable. Ordinary
signs lack colour discrimination in night-time illumination.
Classification of emission colour of phosphorescent material is given in ISO 3864-4:2011, Annex B.
Table 1 — Signs used in natural disaster safety way guidance systems
Safety signs
Supplementary
Type of disaster
signs
Warning signs Safe condition signs
Tsunami
ISO 7010-W056 ISO 7010-E062 ISO 7010-E021
Tsunami
Warning; Tsunami Tsunami evacuation Protection shelter
hazard zone area
Storm surge
ISO 7010-E063
Tsunami evacuation
building
Flood (including flood
from inland waters)
ISO 7010-W077 ISO 7010-E065 ISO 7010-E021
Flood
Warning; Flood zone Outdoor refuge area Protection shelter
Debris flow
ISO 7010-W076 ISO 7010-E065 ISO 7010-E021
Debris flow
Warning; Debris flow Outdoor refuge area Protection shelter
zone
Steep slope failure
TTabablele 1 1 ((ccoonnttiinnueuedd))
Safety signs
Supplementary
Type of disaster
signs
Warning signs Safe condition signs
ISO 7010-W078 ISO 7010-E065 ISO 7010-E021
Landslide Landslide
Warning; Landslide Outdoor refuge area Protection shelter
zone
Large-scale fire
ISO 7010-W073 ISO 7010-E065 ISO 7010-E021
Large scale fire
Warning; Large scale Outdoor refuge area Protection shelter
fire zone
Tornado
ISO 7010-W074 ISO 7010-E021
Tornado
Warning; Tornado Protection shelter
zone
Volcano
ISO 7010-W075 ISO 7010-E021
Volcano
Warning; Active Protection shelter
volcano zone
6.2 Supplementary direction arrow signs
Arrows in direction signs shall be used in conjunction with safety signs to indicate the direction of movement
a person should take to reach the indicated destination. The format of the direction arrow shall be arrow
type D from ISO 3864-3. The meanings of different arrow orientations are shown in Table 2.

Table 2 — Use of supplementary direction arrow signs
Arrow Meaning
Proceed to the right from here
Proceed to the left from here
a) Proceed forward from here
b) Proceed forward and through from here
c) Proceed forward and up from here
a) Proceed up to the right from here
b) Proceed forward and across to the right from here
Proceed down to the right from here
a) Proceed up to the left from here
b) Proceed forward and across to the left from here
Proceed down to the left from here
Proceed down from here
6.3 Supplementary symbols and suitability marking
Because the construction and location of a place of refuge might only be appropriate for particular natural
disasters, it is necessary to indicate the type of disasters for which places of refuge are appropriate. Place of
refuge signs help people who are unfamiliar with the area to properly identify a specific building’s or area’s
suitability or unsuitability as a place of refuge.

In areas where different types of natural disaster can occur, the civil protection agency or authority shall
decide on the suitability of the places of refuge for a certain disaster.
In place of refuge signs and evacuation route signs, the appropriate supplementary symbols given in Table 1
should be used to indicate whether a place of refuge is suitable or unsuitable for protection from hazards
associated with one or more types of natural disaster.
Where it is necessary to warn people that the place of refuge is not suitable for particular types of natural
disaster, an “x” or diagonal bar should be displayed.
A green tick may be used to indicate suitability. The green tick may be replaced by another element
appropriate to the cultural requirements of the target audience.
Examples of suitability and unsuitability markings are presented in Figure 1.
Figure 1 — Examples of markings displaying suitability for floods but unsuitability for debris flow,
landslides or large-scale fires
For examples of signs, see Figures 6 b) and 6 d).
7 Structure of a natural disaster safety way guidance system
7.1 Overview of structure
In order to effectively and efficiently guide people to specific places of refuge when natural disasters occur,
it is important for the system’s signs to provide evacuees with clear, seamless directional information so
they do not lose their way. The structure and content of the guidance system should be consistent with the
information requirements defined in the planning stage (see Clause 5). The structure of seamlessly designed
natural disaster safety way guidance systems is shown in Figure 2.
Natural disaster safety way guidance systems shall provide warning signs, evacuation plan signs, evacuation
route signs and place of refuge signs continuously along the evacuation route in accordance with the risk
mitigation plan.
Figure 2 — Structure of seamlessly designed natural disaster safety way guidance system
7.2 Warning signs
Warning signs shall be installed in locations or areas deemed appropriate, identified as being at risk of
hazard from a particular natural disaster.
Warning signs shall conform to the appropriate ISO 7010 sign. When using supplementary texts, they may
include “Warning” and text giving the meaning of the sign. Additional supplementary text may be provided
giving additional safety information.
Examples of the application of warning signs for natural disasters are shown in Figure 3 and A.1.

Figure 3 — Examples of layouts and contents in a warning sign
7.3 Evacuation plan signs
Evacuation plan signs show the physical relationship between the evacuee and the places of refuge using
the area map as appropriate. They shall provide information identifying the area(s) of risk of the natural
hazard, the locations of places of refuge and the location of evacuees with the symbol “You are here”. Legend
symbols should be from ISO 7001 and ISO 7010.
The following information shall be shown on evacuation plan signs:
a) location of places of refuge;
b) location of current place (“You are here”).
The following information can be shown on the evacuation plan sign:
— location of emergency services, such as drinking water and first aid;
— location of evacuation routes;
— location of landmarks;
— hazard zones (see Figures A.2, A.3 and A.4);
— legend;
— marking of the hazardous zone by warning signs and colouring;
— different sources of warning information.
Examples of the application of evacuation plan signs for other natural disasters are presented in Figure 4
and A.2.
a) Area map of safety way guidance
b) Projected flood water depth
Figure 4 — Examples of evacuation plan signs
7.4 Evacuation route signs
The direction and the distance to the place of refuge shall be shown on the evacuation route signs. Evacuation
route signs shall be installed with a directional arrow showing the direction of evacuation, distance to the
place of refuge and the safe condition sign with a suitable natural disaster supplementary sign. Evacuation
route signs shall use the appropriate safety sign from Table 1 and direction arrow from Table 2.

The direction given by the arrow is used to indicate the direction of movement of evacuation. Evacuation
route signs (such as those given in Figure 6) shall be used exclusively to indicate the direction to be followed
by occupants. Graphical symbols with a person running (outdoor refuge area, tsunami evacuation area and
tsunami evacuation building) shall always be used with a supplementary arrow and shall be consistently
displayed at all installed positions on the evacuation route. Examples of a safe condition sign with a
supplementary direction arrow sign are presented in Figure 5.
Figure 5 — Examples of a safe condition sign with a supplementary direction arrow sign
The evacuation route sign shall show the following information in the event of natural disasters, as a
consequence of the mitigation plans:
a) distance to the place of refuge;
b) sign and description or identifier showing the place of refuge;
c) supplementary sign showing the suitable type of natural disaster.
The graphical symbols used on evacuation route signs can be arranged in several ways depending on the
space available for the display. Examples of evacuation route sign layouts are presented in Figure 6 and A.3.
a) Layout example of a vertical sign

b) Layout example of a vertical sign with not suitable marking
c) Layout example of a horizontal sign
d) Layout example of a square sign

e) Layout example of a horizontal sign for one disaster
Figure 6 — Examples of evacuation route sign layouts
7.5 Place of refuge signs
Place of refuge signs show the place is safe for refuge from certain types of natural disasters.
The appropriate safe condition sign from ISO 7010 (see Table 1) shall be used for place of refuge signs, such
as tsunami evacuation area, outdoor refuge area, tsunami evacuation building and protection shelter.
Signs shall be installed in (a) prominent place(s) at the designated location(s) and include suitability marking
for the types of natural disaster. Signs should show the following information in the event of natural
disasters, as a consequence of the mitigation plans:
a) when appropriate, the safe condition sign and the name of the location of the place of refuge;
b) when appropriate, the applicable type(s) of natural disaster;
c) when appropriate, the types of natural disaster for which it is not suitable marked with “x” or a diagonal
bar, “\”.
Examples of place of refuge sign layouts are shown in Figure 7 and A.4.
a) Layout example of a vertical sign

b) Layout example of a horizontal sign
c) Layout example of a horizontal sign for one disaster
Figure 7 — Examples of place of refuge sign layouts
8 Bilingual signs
The use of the local languages might be sufficient when international users are not a concern. For situations
that require international understanding, English should be used in addition to the official local languages.
Layout examples of bilingual signs are presented in Figure 8.
a) Example of a bilingual flood evacuation plan sign

b) Example of a bilingual warning sign
Figure 8 — Examples of layouts of bilingual signs
9 Identifiability and legibility of signs under daylight and night-time conditions
This document is intended to be used for safety way guidance for the outdoors. Natural disaster safety way
guidance system signs are installed outdoors and are subject to illumination from daylight, night light and
stray or borrowed lighting from buildings, pathways and street lighting.
Signs shall be identifiable and legible under daylight and night-time conditions. In the daytime, the
illumination of the sign should normally be by natural daylight. The light incident on signs is a combination
of direct and scattered light.
At night-time the natural light is less effective for ordinary signs, such that signs need to be either light-
emitting, such as phosphorescent signs, or externally illuminated by a light source, such as by street
lighting or an integral light source. The failure of the power supply to artificial light sources should also be
considered.
Some types of lighting, such as low-pressure sodium street lighting, do not enable effective colour
recognition and are therefore unlikely to be suitable for the illumination of the sign components of the safety
way guidance system.
In choosing the application of either ordinary signs or phosphorescent signs, information on the identifiability
and legibility of ordinary signs and phosphorescent signs and sizing, given in Annex B, should be considered.
For phosphorescent signs, the whole surface of the sign carrier should be phosphorescent. If this is not
practical, at least the graphical symbols and directional arrows should use phosphorescent material in order
to be identifiable.
The minimum requirement for the luminance decay properties of phosphorescent materials used in
components of the natural disaster safety way guidance system shall be as given in Table 3 for the category
of luminance classification. The test conditions are given in Annex C.
The laboratory test method for measurement of photopic luminance of phosphorescent materials shall be in
accordance with Annex D.
Products should be marked with the relevant classification.

Table 3 — Luminance decay classification of outdoor phosphorescent safety signs
Minimum luminance at 720 min decay time
Classification
mcd/m
I 3
II 10
10 Installation of natural disaster safety way guidance systems
10.1 General
The following principles should be applied when installing natural disaster safety way guidance systems:
a) Install signs in a prominent place within the normal visual field.
b) Make signs stand out from the surrounding environment.
c) Select locations such that the signs themselves do not pose a risk to the environment.
d) Make sure each sign is clearly visible and legible from the intended viewing positions. Also check the
visibility of the system at night-time. If possible, an open space should be maintained in front of each
sign so those with impaired vision can approach the sign to read it closely.
e) Ground surface mounted signs can be effective as supplementary signs in places with limited sight
distance or places where vertical installation is not possible. It is necessary to check the performance
and effect of the phosphorescent materials in snowy regions or places where rainwater can change the
sign installation environment significantly, since they might not fully exhibit the expected performance.
The sites of installation and other matters related to the natural disaster safety way guidance system shall
be decided by the relevant civil protection agency.
For distance factors and sizing visual elements, see Annex B.
10.2 Sign positioning
Interval is an important factor for deploying natural disaster safety way guidance signs. In order to guide
people continuously, all respective signs should be installed seamlessly from the hazardous zone to the final
evacuation facility at appropriate intervals.
In particular, at an intersection where the road branches off in different directions, the directional arrow
indicating the direction of evacuation to a designated place of refuge should be identifiable from safe
positions. Evacuees might feel uneasy if the interval between signs becomes longer. The sign interval should
be carefully studied on-site to check that the next sign can be identified from the position of the previous
sign. An example of installed evacuation route signs is presented in Figure 9.
Figure 9 — Example of layout of an evacuation route sign installed before a crossroads

For phosphorescent materials, where practical, select locations where the signs are exposed to direct sunlight,
preferably in the afternoon. Phosphorescent signs should not be placed in locations in permanent shadow.
10.3 Durability
Natural disaster safety way guidance system sign materials should be selected considering the environment
of the installation site. The following factors should also be considered:
— durability of the base plate materials;
— durability of displays;
— colour selection and light fastness;
— resistance to abrasion caused by the flow of people and repeated cleaning;
— waterproofness;
— resistance to corrosion, such as that caused by seawater spray;
— resistance to pasting of paper or flyers and writing of graffiti;
— flame resistance;
— types of accessories and their suitability;
— resistance to wind pressure;
— protection against excessive UV and moisture.
Signs to be installed should be suitable for the expected environmental conditions of the site of installation.
Installers and designers of signs should confirm the above points by checking the material certificates and
requesting approval of materials and other documents submitted by the supplier.
11 Repair, maintenance and inspection
Natural disaster safety way guidance sign systems should be cleaned and inspected periodically and
countermeasures taken when any defects are found.
A sign which has been damaged or faded should be replaced. A sign should be removed when its function is
no longer needed.
Luminance of phosphorescent signs should be measured at the site of installation. If the measurement result
fails to reach the specified level, the sign should be replaced.
Maintenance should be conducted at any time as required. Inspections should be performed according to the
instructions of the sign manufacturers.

Annex A
(informative)
Examples of installations of natural disaster safety way guidance systems
A.1 Examples of warning sign installations
Examples of warning sign installations are shown in Figure A.1.

a) Tsunami or storm surge warning sign with  b) Debris flow warning sign installed on the
additional information related to altitude roadside at the foot of a mountain
installed on the sea wall close to the coast

c) Flood warning sign with projected flood water d) Steep slope failure or landside warning sign
depth supplementary sign installed near a river installed near a steep slope of a mountain be-
path hind houses
e) Temporary sign installed when eruption foreseeable
Figure A.1 — Examples of warning sign installations
A.2 Examples of evacuation plan signs
A.2.1 Additional information for disaster precaution
The precaution areas for tsunamis and storm surges or hazard zones for debris flow, steep slope failure and
landslides should be marked appropriately on the evacuation plan sign.
An example of disaster precaution areas for tsunamis is shown in Figure A.2.
Figure A.2 — Example layout of an evacuation plan sign for disaster precaution areas for tsunamis,
with available facilities
An example of an evacuation plan sign for hazard zones for debris flow is shown in Figure A.3.

NOTE This example shows special (high-risk) sediment-related disaster hazard zones, sediment-related disaster
hazard zones and area outside of sediment-related disaster hazard zones.
Figure A.3 — Example layout of an evacuation plan sign for disaster hazard zones for debris flow
An example of an evacuation plan sign for hazard zones for steep slope failure and landslides is shown in
Figure A.4.
NOTE This example shows special (highest-risk) sediment-related disaster hazard zones, sediment-related
disaster hazard zones and area outside of sediment-related disaster hazard zones.
Figure A.4 — Example layout of an evacuation plan sign for disaster hazard zones for steep slope
failure and landslides
A.2.2 Alternative evacuation routes
Evacuation plan signs should show alternative routes that can be used under differing circumstances as well
as showing accessible routes for people with mobility challenges (e.g. people in wheelchairs).
An example of alternative routes and accessible routes is shown in Figure A.5.

Figure A.5 — Example layout of an evacuation plan sign for alternative evacuation routes and
accessible routes in case of flood
A.2.3 Examples of evacuation plan sign installations
Examples of evacuation plan sign installations are shown in Figures A.6 and A.7.
Figure A.6 — Example of a tsunami evacuation plan sign

Figure A.7 — Example of a flood evacuation plan sign installed in a conspicuous place
A.3 Examples of evacuation route signs
A.3.1 Examples of evacuation route sign installations
Examples of evacuation route sign installations are shown in Figure A.8.

a) Tsunami evacuation route sign installed on a b) Tsunami evacuation route sign installed on a
mountain path wall in an urban area

c) Fire disaster evacuation route sign  d) Storm surge evacuation route sign
installed on a utility pole and on a path installed on the inside of a dyke

e) Self-standing debris flow and landside evacua- f) Debris flow evacuation route sign installed
tion route sign installed on a path on a pole in an area surrounded by a mountain
running along the river and a river

g) Volcano evacuation route sign installed in h) Tornado evacuation route sign installed on
front of a tunnel which is a protection shelter the exterior wall of a protection shelter
Figure A.8 — Examples of evacuation route sign installations
A.3.2 Additional information located near evacuation route signs
An example of projected flood water depth is shown in Figure A.9.
Figure A.9 — Example of flood water depth (historical) installed with evacuation route sign
installation
A.4 Examples of place of refuge sign installations with suitable and not suitable marking
Examples for place of refuge sign installations are presented in Figure A.10.

a) Tsunami evacuation building sign installed on b) Tsunami evacuation area sign with
1st floor and top of the building suitable and not suitable marking installed
in plain view
c) Self-standing sign for flood and large-scale d) Place of refuge sign for flood, tsunami and
fire with suitable and not suitable marking in- large-scale fire with suitable and not suitable
stalled in a conspicuous place near the marking installation on a school gate
entrance of a protection shelter
Figure A.10 — Examples of place of refuge sign installations

Annex B
(informative)
Distance factors and sizing visual elements
B.1 Distance factors
B.1.1 General
The signs in natural disaster safety way guidance systems consist of different graphical symbols and text,
which have different maximum viewing distances for identifiability and legibility. Distance factors, z , can
be used to give the maximum horizontal viewing distances for the different components.
The recommended maximum viewing distance for a graphical symbol or text of height h, in millimetres
(mm), can be calculated from the following equation:
l = zh
where
l is the required viewing distance, in millimetres (mm);
z is the relevant distance factor.
NOTE Measurement of sign height is given in ISO 20712-3:2020, Table 1.
z is associated with viewing from a position perpendicular to the sign at a distance
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