SIST EN ISO 22359:2025

SLOVENSKI STANDARD
01-oktober-2025
Varnost in vzdržljivost - Smernice za utrjena zaklonišča (ISO 22359:2024)
Security and resilience - Guidelines for hardened protective shelters (ISO 22359:2024)
Sicherheit und Resilienz - Leitfaden für verstärkte Schutzräume (ISO 22359:2024)
Sécurité et résilience - Lignes directrices relatives aux abris durcis (ISO 22359:2024)
Ta slovenski standard je istoveten z: EN ISO 22359:2025
ICS:
03.100.01 Organizacija in vodenje Company organization and
podjetja na splošno management in general
91.040.99 Druge stavbe Other buildings
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 22359
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2025
EUROPÄISCHE NORM
ICS 03.100.01; 91.040.99
English Version
Security and resilience - Guidelines for hardened
protective shelters (ISO 22359:2024)
Sécurité et résilience - Lignes directrices relatives aux Sicherheit und Resilienz - Leitfaden für verstärkte
abris durcis (ISO 22359:2024) Schutzräume (ISO 22359:2024)
This European Standard was approved by CEN on 27 July 2025.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 22359:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
The text of ISO 22359:2024 has been prepared by Technical Committee ISO/TC 292 "Security and
resilience” of the International Organization for Standardization (ISO) and has been taken over as
of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by January 2026, and conflicting national standards shall
be withdrawn at the latest by January 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 22359:2024 has been approved by CEN as EN ISO 22359:2025 without any modification.

International
Standard
ISO 22359
First edition
Security and resilience —
2024-08
Guidelines for hardened protective
shelters
Sécurité et résilience — Lignes directrices relatives aux abris durcis
Reference number
ISO 22359:2024(en) © ISO 2024
ISO 22359:2024(en)
© ISO 2024
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 22359:2024(en)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Design of a shelter . 2
4.1 Design process .2
4.2 Design criteria .3
4.2.1 Hazards .3
4.2.2 General parameters .4
4.2.3 Type and purpose of a shelter .4
4.2.4 Location .5
4.3 Shelter sections and layout design .5
4.3.1 General .5
4.3.2 Entrance and exit passages .6
4.3.3 Living section .7
4.3.4 Service section .8
4.3.5 Technical section .9
4.4 Structural design .10
4.4.1 General .10
4.4.2 Calculation of the loads .11
4.4.3 Bedrock and concrete shelters .11
4.5 Heating, ventilation, air conditioning (HVAC) and other mechanical systems. 12
4.5.1 Ventilation and air conditioning . 12
4.5.2 Water supply and sewage . 13
4.6 Electrical and electronic systems . 13
4.6.1 Power generation . 13
4.6.2 External communication . 13
4.6.3 Internal communication . 13
4.6.4 Situational awareness. 13
4.6.5 Intentional electromagnetic interference IEMI (EMP and HPM) protection . 13
4.6.6 Monitoring and control . 13
4.7 Shelter protective equipment .14
4.7.1 General .14
4.7.2 Blast protection .14
4.7.3 Gas tightness .14
4.7.4 Tightness of penetrations . 15
4.7.5 Ground shock isolation . 15
4.7.6 CBRN protection . 15
4.7.7 Removal of carbon dioxide and addition of oxygen.16
4.8 Safety and security .16
4.8.1 Physical safety and security .16
4.8.2 Fire safety .16
5 Commissioning of a shelter . 17
6 Use and maintenance of a shelter . 17
6.1 Sheltering cycle .17
6.2 Normal time use .18
6.3 Activation period – preparing the shelter for crisis time use.18
6.4 Crisis time – use of the shelter in various sheltering modes .19
6.5 Deactivation period – preparing the shelter for normal time use .19
6.6 Modifications and alterations during the service life of a shelter .19
Annex A (informative) Sheltering modes .20

iii
ISO 22359:2024(en)
Annex B (informative) Examples of shelters.23
Bibliography .26

iv
ISO 22359:2024(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,
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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
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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related to conformity assessment, as well as information about ISO's adherence to the World Trade
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This document was prepared by Technical Committee ISO/TC 292, Security and resilience.
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.

v
ISO 22359:2024(en)
Introduction
0.1  General
This document provides guidelines for hardened protective shelters used for protection of people, assets, and
functions supporting critical infrastructures during a disaster through isolating them from the hazardous
environment and thus protecting them against the dangerous effects of the hazard.
Protection of people is based on international treaties and protection of the civilian population when their
country is at war, but also in peacetime is primordial. Article 3 of the United Nations Universal Declaration
[2]
of Human Rights gives everyone the right to life, liberty, and security. Furthermore, the fourth treaty of
[1]
the Geneva Convention proclaims the civilian populations right to be protected in armed conflicts.
0.2  Hazards and disasters
Hazards create harmful effects such as loss of life, injury or other health effects, property damage, social
and economic disruption or environmental degradation. Hazards can be single, sequential or combined in
their origin and effects, as hazardous events can occur alone, simultaneously, cascading or cumulatively.
If the hazard(s) cannot be mitigated, they can result in a disaster. During a disaster, citizens typically
need some type of societal protection against the effects of the hazard. Most societies have planned and
implemented actions to protect their citizens against hazards and their effects. These actions are sometimes
referred to diversely as civil protection, civil defence, crisis management, emergency management,
emergency preparedness, contingency planning, civil contingency and civil aid.
The preventive measures and protective efforts depend on the threat assessments studying the risks created
by various hazards or combinations of them. The threat assessments usually address all four stages of the
disaster management cycle (mitigation, preparation, response and recovery).
When a hazard occurs, it can cause effects that can affect the citizens. The citizens can be directly
injured or harmed by the failure of critical infrastructure and the denial of vitally important functions of
the society. This document focuses only on hazards and effects that can be mitigated through hardened
protective shelters. Some other common and well-known methods to protect citizens are mass evacuations,
quarantines and redundant systems.
0.3  Hardened protective shelter
A hardened protective shelter is a purpose-built structure, which is blast resistant (designed to withstand
the effects of a blast with a predefined force) and gastight (so completely closed that no gases can get in or
out), for protection of shelter occupants against the effects of disasters by isolating them from the hazardous
environment.
The shelter is hardened against the mechanical effects of disasters by means of a heavily reinforced concrete
or bedrock shield. This distinguishes it from rapidly erected temporary shelters such as lightweight canvas
weather shelters, other tarp tent shelters as well as metal and container shelters.
The shelter can sustain the life of the occupants for an extended period of time should the anticipated threat
so require, by maintaining a sufficient internal overpressure and using purified filtered air to prevent entry
of all possible toxic substances that the ambient air can contain.
0.4  Use of shelters
The civil protection shelter programs are managed by civilian authorities. The primary purpose of hardened
protective shelters is to protect citizens against the effects of weapons during wars or warlike situations, but
they can also be used for safeguarding them in case of natural hazards or industrial accidents threatening
civilian life.
Military shelters are usually hardened against weapon effects, such as blast, chemical, biological, radiological
and nuclear (CBRN) warfare, and in many cases also against the effects of an electromagnetic pulse (EMP).
They are used as command-and-control centres, for protection of troops and as fortified hangars for aircraft
and other military assets.
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ISO 22359:2024(en)
There are several industry branches with a potential risk of accidents involving of flammable, explosive,
poisonous or radiating materials. The accident is often caused by an explosion, but also natural effects such
as flooding, or earthquake can trigger an incident. The industrial market segment comprises, among others,
chemical industries, nuclear power plants, hospitals, industrial command and control centres and data
storage facilities.
vii
International Standard ISO 22359:2024(en)
Security and resilience — Guidelines for hardened protective
shelters
1 Scope
This document provides guidelines for the design, use and maintenance of hardened protective shelters
(hereafter referred to as “shelters”). It specifies guidance on the layout, structures, equipment and actions
related to a shelter.
This document is intended for organizations or individuals responsible for or involved in decision-making,
planning, implementation, administration, use or upkeep of shelters, such as local, regional and national
governments, civil protection agencies, first responders and businesses such as designers, constructers and
equipment suppliers.
This document does not cover the minimum requirements or exact specifications for the properties of or
actions related to a shelter; nor does it cover rapidly erected temporary shelters, such as lightweight canvas
weather shelters, other tarp tent shelters, or metal and container shelters. Military shelters are subject to
additional requirements which are outside the scope of this document.
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 22300, Security and resilience — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 22300 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
blast resistant
withstanding the effects of a blast with a predefined force
3.2
gastight
preventing gas from entering or escaping
3.3
hardened protective shelter
blast resistant (3.1) and gastight (3.2) facility with a capability to maintain internal overpressure with air
purified from toxic agents
3.4
normal time
period during which there is no such crisis that would cause the shelter to be activated as during crisis time use

ISO 22359:2024(en)
4 Design of a shelter
4.1 Design process
The design of a shelter should be based on operational requirements, depending on the purpose of the
shelter and the applicable threat scenario(s). The design process of a shelter is practically similar to that of
any capital project. The entire design process from the first conceptual idea to the beginning of construction
is presented as a flowchart in Figure 1.
Figure 1 — Design process of a shelter
The operational, architectural and engineering design is described in detail in Figure 2.

ISO 22359:2024(en)
Figure 2 — Detailed design process of a shelter
4.2 Design criteria
4.2.1 Hazards
A shelter gives protection against various effects of external hazards. Table 1 gives examples of hazards,
against which the shelter can offer effective protection.
Table 1 — Hazards and examples of their origins
Hazard Examples of origin of the hazard
Human-caused hazards (intentional malevolent actions) War
Terrorist act
Civil disturbance
Sabotage
Technological hazards (accidents or failures of systems and struc- Industrial accident
tures)
Transport accident
Storage accident
Nuclear power plant accident
Natural hazards (acts of nature) Volcanic eruptions
Extreme storms
Asteroids, meteorites
Solar flares
The effects of hazards can be either mechanical loads caused by various physical forces exerted on the
shelter (see 4.4.1) or other effects caused by various toxic agents, radiation or thermal energy (see 4.7.6).

ISO 22359:2024(en)
4.2.2 General parameters
The following general parameters for shelter design should be considered:
a) Purpose of the shelter
b) Local environmental conditions
c) Capacity, volume and nominal floor space per person
d) Potential overcrowding
e) Estimated activity level of the occupants
f) Protective functions (expected threats, protection level, sheltering time and pertinent sheltering modes)
g) Habitability criteria for the occupants [air change rate, carbon dioxide (CO ) and oxygen (O )
2 2
concentration ranges, temperature and humidity]
h) Life cycle management
i) Cost-effect analysis
4.2.3 Type and purpose of a shelter
The recommendations in this document can apply principally to all types and sizes of shelters. They are
not intended to be seen purely as technical specifications but rather as descriptions of various functions
of a shelter. The technical implementation of these functions varies according to the type and size of the
shelter, local climatic conditions and the threat scenarios. The presented technical solutions form a basis
for the shelter design. In case some function or recommendation does not apply to a certain shelter size,
a pertinent note is provided. The typical sizes of shelters for civil protection are listed in Table 2. Annex B
gives examples of typical shelters.
Table 2 — Typical shelter sizes for civil protection
Type of shelter Purpose and the number of occupants in the shelter
Small shelter The shelter is designed for protection of inhabitants of one or a few residential
buildings. A small shelter is typically designed for a limited number of occu-
pants up to 150 persons and is usually constructed of reinforced concrete.
Medium-sized shelter The shelter is designed for protection of inhabitants, operatives or visitors of a
large estate such as a sizeable residential building, an office block, a shopping
mall or a hotel. A medium-sized shelter is typically designed for occupants up
to 1 000 persons to accommodate the residents and visitors at the estate and is
usually constructed of reinforced concrete.
Large shelter The shelter is designed for protection of inhabitants, operatives, visitors and
people in transit in a town district. A large shelter is typically designed for a
large number of occupants up to 10 000 persons and is usually constructed of
reinforced concrete or excavated in the bedrock.
Shelter for the protection of civil- The shelter is designed for the protection of industrial or other assets and the
ian assets and functions functions supporting critical infrastructure such as command and control
centres and data centres. The primary design criterion for a shelter for assets
and functions is not the number of occupants but the design is dictated by the
required functions of the shelter.
Shelter for protection of military The shelter is designed for protection of military assets such as weapons, vehi-
assets and functions cles or other equipment, as well as critical functions and infrastructure. These
shelters are outside the scope of this document, as they could not be seen as
[1]
shelters for civil protection as defined in the Geneva Convention.

ISO 22359:2024(en)
4.2.4 Location
4.2.4.1 Surroundings
A shelter should be located in a suitable place to provide appropriate protection and easy access.
The design should maximize the opportunities to integrate the shelter into the surrounding development.
4.2.4.2 Distance to reach a shelter
A shelter primarily designed for protection of citizens should be easily accessible by foot with a limited
distance from the place of residence or workplace of the shelter users.
4.2.4.3 Distance between shelters
In a group of shelters, the distance between individual shelters should be based on the applied threat
scenario and risk analysis.
4.2.4.4 Markings and accessibility of a shelter
In the design of markings and accessibility of a shelter, the following should be considered:
a) capacity of the routes and ways equal to the maximum number of users, taking into account their
probable direction of arrival;
b) the accessibility of the shelter by persons with disabilities;
c) clear markings (large and visible text with the international symbol for civil protection, a blue triangle
on orange background) of entrance routes and entrance ways.
The international symbol for civil protection as defined in item 4, Article 66 of the Protocol Additional to
[1]
the Geneva Conventions of 12 August 1949, can be used. See Figure 3. The CMYK codes of the colours are
C88 M63 Y11 K25 (blue) and M50 Y96 (orange).
Figure 3 — International symbol for civil protection
4.3 Shelter sections and layout design
4.3.1 General
In the layout design of a shelter, the following should be considered.
a) It is recommended that the architecture of the layout is based on the room space programme, expected
traffic, communication and interaction between spaces, and noise control.

ISO 22359:2024(en)
b) A shelter is normally divided in several sections, which should all be incorporated in the layout design.
The shelter may include:
— entrance and exit passages: the area for entering and exiting the shelter;
— living section: the area where people dwell, sit, sleep and work;
— service section: the area with service facilities, storage and toilets;
— technical section: the area containing the technical facilities and machinery.
c) In a small shelter, a room may contain more than one section. Similarly, several functions can be
contained in one room.
d) In a medium-sized or large shelter, it can be necessary to divide the sections into separate rooms either
permanently or when needed.
e) Certain parts of the shelter, such as the technical area, entrances, emergency exit and storage areas,
may be restricted from unauthorized persons, clearly marked and locked.
f) Medical, cultural, and other human factors related to the use the shelter.
4.3.2 Entrance and exit passages
4.3.2.1 General
The principle for design of entrance and exit passages is described in Figure 4.
NOTE In a small shelter, it is possible that separate pressure and air locks are not feasible, as the pressure and
gastight protection barrier can be combined into a single barrier (see 4.3.5.2).
Key
1 entrance and exit lane(s) 2 pressure lock
3 blast protection barrier 4 gastight barrier
(blast-proof doors and valves) (gastight doors and valves)
5 air lock 6 gastight and blast protected area
7 flushing the locks with air 8 decontamination facilities
NOTE This figure is not to scale.
Figure 4 — Pressure and air locks

ISO 22359:2024(en)
In the design of the entrance and exit passages, the following should be considered:
a) the logistics related to managing and supplying the shelter;
b) the number of persons sheltered and the directions and rate of entering and exiting;
c) the width and number of passage lanes;
d) the size and number of entrance doors;
e) accessibility for persons with disabilities;
f) different scenarios, also considering the possibility of blocked entry or exit passages;
g) blast wave mitigation measures (pressure lock and angular passages);
h) contamination prevention and decontamination measures (air lock).
4.3.2.2 Pressure lock
A pressure lock is a space between the outer and the inner blast resistant door; it protects the shelter
entrance from blast effects. In the design of the pressure lock, the following should be considered:
a) preventing a simultaneous opening of the blast resistant doors on both sides of the pressure lock;
b) flushing of the pressure lock with exhaust air from the shelter to remove any contaminated air.
4.3.2.3 Air lock
An air lock is a space between the inner blast resistant door and the gastight door at the gastight barrier;
it protects the shelter entrance from contamination and enables decontamination of persons entering the
shelter. In the design of the air lock, the following should be considered:
a) flushing of the air lock with exhaust air from the shelter to remove of any contaminated air;
b) facilities for decontamination such as shower, water tap, sink and floor drain as well as waste
management of contaminated garments.
4.3.2.4 Emergency exits
A shelter should have at least one emergency exit. In the design of the emergency exit(s), the following should
be considered:
a) opening to a different direction from the entrance(s);
b) reaching outside the estimated collapse area of the structures above or adjacent to the shelter;
c) designing the emergency exit ways or tunnels as short as possible to prevent suffocation of people
exiting the shelter in an emergency;
d) emergency lights for the pathway leading towards emergency exit.
4.3.3 Living section
In the design of the living section and the allocation of space for the occupants and various necessary
functions, the following should be considered:
a) space allocation to the occupants for sleeping, sitting and standing as well as for the necessary furniture;
b) access to the various facilities of the service section;
c) human management (including hygiene control and social aspects such as safety and security);

ISO 22359:2024(en)
d) potential overcrowding.
NOTE The above aspects are normally regulated by operational requirements.
4.3.4 Service section
4.3.4.1 General
In the design of the service section, the following should be considered:
a) toilets;
b) first aid and medical care;
c) waste disposal;
d) water and food storage;
e) equipment storage;
f) other service functions.
4.3.4.2 Toilets
In the design of toilets, the following should be considered:
a) the number and capacity of toilets;
b) type of toilets (e.g. flushing toilets, dry toilets);
c) management and logistics of human waste;
d) prevention of odours;
e) accessibility for disabled people;
f) hand cleaning facilities.
4.3.4.3 First aid and medical care
In the design of first aid and medical care, the following should be considered:
a) the capacity, level and quality of medical services, equipment and supplies;
b) plan for handling of deceased people.
4.3.4.4 Waste disposal
In the design of waste disposal, the following should be considered:
a) an area close to the toilets for disposal of human waste;
b) an area close to the entrance airlock for disposal of contaminated garments and materials after
decontamination procedures;
c) facilities for disinfection of the toilets after emptying.
4.3.4.5 Water and food storage
In the design of the water and food storage, the following should be considered:
a) storage with a capacity for a full occupancy (including potential overcrowding) over a maximum
sheltering period;
ISO 22359:2024(en)
b) thermal conditions in the shelter;
c) safe and secure storage with a space for distribution of water and food;
d) filling and replenishing of the storage.
4.3.4.6 Equipment storage(s)
In the design of the equipment storage, the location and capacity should be considered.
Examples of equipment include medical care, firefighting, rescue, clothes, dry toilets, tools, spare CBRN
filters and any equipment needed to convert the shelter into crisis time operation.
4.3.4.7 Other service areas
Other service areas such as kitchen and baby changing room should be considered.
4.3.5 Technical section
4.3.5.1 General
In the design of the technical section, the following should be considered:
a) dirty and clean technical areas;
b) placement of technical equipment;
c) placement of power generation (see 4.6.1);
d) ground water and flooding control;
e) command and control.
4.3.5.2 Dirty and clean technical areas
The dirty and clean technical areas are parts of the technical section separated by a gastight protection
barrier, which consists of gastight wall(s) with gastight equipment in all openings and penetrations, as
shown in Figure 5.
The dirty technical area is the area outside the gastight protection barrier but inside the blast protection
barrier. In the design of the dirty technical area, the following should be considered:
a) locating cooling system components such as condensing units and cooling radiators in the dirty technical
area to enable the use of outside air for cooling;
b) minimizing the size of the dirty technical area and the amount of equipment housed within it.
The clean technical area is the area inside the blast protection barrier and the gastight protection barrier.
Any mechanical and electrical equipment potentially requiring service during sheltering should be located
in the clean technical area.
NOTE In a small shelter, it is possible that it is not feasible to install separate barriers for blast and gastight
protection; in this case, there is no dirty technical area, but the functions a) and b) above are located in the clean
technical area.
ISO 22359:2024(en)
Dirty technical area outside the gastight protection barrier but
inside the blast protection barrier (all equipment requiring large
volumes of air)
Clean technical area inside the gastight protection barrier and
the blast protection barrier (all equipment that requires service
during sheltering)
Blast protection barrier
Gastight protection barrier
NOTE This figure is not to scale.
Figure 5 — Clean and dirty technical areas
4.3.5.3 Placement of technical equipment
In the design of the placement of technical equipment, the following should be considered:
a) convenience to the shelter occupants;
b) easy access for the shelter operators and accessibility to all equipment and systems;
c) reduction of noise transfer;
d) reduction of risk of contamination when handling the pre-filters and the CBRN filters.
4.3.5.4 Ground water and flooding control
In the design of the ground water and flooding control, the following should be considered:
a) passive water level control (self-draining system);
b) active water level control (ducting, sumping, pumping and monitoring);
c) prevention and control of water leaks and seepage;
d) measures against buoyancy (e.g. anchoring).
4.3.5.5 Monitoring, control and management
In medium-sized and large shelters, a specific control area can be needed for monitoring, control and
management of all sheltering functions.
4.4 Structural design
4.4.1 General
A shelter gives protection against pressure waves, ground shocks, fragment impacts and collapse loads in
addition to the ordinary basic mechanical loads, as explained in Table 3.

ISO 22359:2024(en)
Table 3 — Mechanical loads exerted on a shelter
Load Causes
Basic mechanical load Overlying structure, payload, wind load, snow load, load by earth pressure and earthquakes
Pressure load Pressure wave (positive and negative phases) propagating in the air
Ground shock Shock wave propagating in the soil
Collapse load Debris from collapsing overhead or adjacent building(s)
Fragment load Impact of a high kinetic energy flying fragment or projectile
In the structural design of a shelter, the following should be considered:
a) reinforcing the shelter so that it can withstand all the mechanical loads described in Table 3, according
to the applied threat scenarios;
b) selecting materials with properties and quality fulfilling the requirements of the intended protective
capability of the shelter;
c) refraining from using frangible or spalling and delaminating materials (such as mortar or masonry);
d) designing the structure for a slow and highly deforming behaviour in case of failure;
e) mounting all equipment and installations so that their fittings tolerate movements of the shelter
structure due to shock loads without breaking the fittings loose;
f) minimizing noise for the living and service sections.
NOTE During normal time, easily removable internal walls and partitions that do not cause damage to the shelter
structures or equipment can be used.
4.4.2 Calculation of the loads
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