ISO 22341-2:2025

International
Standard
ISO 22341-2
First edition
Security and resilience — Protective
2025-06
security —
Part 2:
Guidelines for crime prevention
through environmental design for
residential facilities
Sécurité et résilience — Sécurité préventive —
Partie 2: Lignes directrices pour la prévention de la criminalité
par la conception environnementale dans les structures
d'hébergement
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 . 1
4 Understanding crime and security risk in residential facilities . 2
5 Key considerations for residential facilities’ CPTED . 3
6 CPTED strategies for residential facilities . 3
6.1 General .3
6.2 CPTED concepts for residential facilities .4
6.2.1 Surveillance .4
6.2.2 Access control, site/target hardening and territorial reinforcement .5
6.2.3 Image and maintenance .6
6.2.4 Activity support .6
6.3 Specific CPTED strategies by the hierarchy of spaces.6
6.3.1 General .6
6.3.2 Public space . .8
6.3.3 Semi-public space .9
6.3.4 Semi-private space.11
6.3.5 Private space . 12
6.4 CPTED process and principles for residential facilities . 12
Annex A (informative) Conceptual CPTED for residential facilities by spatial hierarchy .13
Bibliography . 14

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
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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
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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.

iv
Introduction
This document is intended to provide guidelines on crime prevention through environmental design (CPTED)
to reduce the opportunity for crime and the fear of crime, creating secure and sustainable residential
housing environments.
This document is aligned with the process and general principles described in ISO 22341, extended to cover
residential facilities.
Figure 1 illustrates the framework of CPTED for residential facilities.
Figure 1 — Framework of CPTED for residential facilities
This document explains the concept of crime and security risk for residential facilities, and the related risk
factors.
This document also outlines CPTED strategies for residential facilities, including specific security strategies
for different types of spaces in line with the spatial hierarchy of dwelling environments to prevent them
from crime and security risks.
This document is not intended to provide an exhaustive listing of detailed design, architectural or physical
security CPTED implementation strategies or restrict the potential applications to only those examples
provided in this document.
v
International Standard ISO 22341-2:2025(en)
Security and resilience — Protective security —
Part 2:
Guidelines for crime prevention through environmental
design for residential facilities
1 Scope
This document provides guidelines to organizations for establishing general and specific strategies to
prevent and reduce crime and the fear of crime at new or existing residential facilities, in single or multiple
units. This document builds on the concepts and processes described in ISO 22341, in the context of
residential facilities.
It provides recommendations on countermeasures and actions to address crime and security risks to people
and property, in dwellings and their immediate surroundings, by implementing crime prevention through
environmental design (CPTED) strategies in an effective and efficient manner.
Within this document, the term “security” is used in a broad manner to include all crime, safety and security-
specific applications. Therefore, this document is applicable to public and private organizations, regardless
of type, size or nature.
This document applies to organizations responsible for the residential facility including a real estate
company, developer or landlord.
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
Internet of Things
IoT
infrastructure of interconnected entities, people, systems and information resources together with services
which processes and reacts to information from the physical world and virtual world
[SOURCE: ISO/IEC 20924:2024, 3.2.8]

3.2
traffic calming
encouragement of restrained and considerate behaviour by means such as road humps and reductions in
width of the carriageway
[SOURCE: ISO 6707-1:2020, 3.1.3.52]
3.3
wayfinding
way in which people orient themselves in physical space and navigate from place to place
4 Understanding crime and security risk in residential facilities
The crime and security risks associated with residential dwellings and environments are of a specific nature
and type.
EXAMPLE Domestic burglary.
NOTE See ISO 22341:2021, A.2.2 for further details on residential crimes (including housebreaking and arson).
The organization should evaluate relevant threats and vulnerabilities, and the scope of security measures
aimed at reducing crime, anti-social behaviour and the fear of crime in residential areas.
There are many risk factors that can influence whether an offence is committed, such as the neighbourhood
layout, building design and the lack of site/target hardening measures.
The high level of such crime risk requires a proportionate level of CPTED and security measures.
Many offences are committed because perpetrators take advantage of opportunities such as easy access,
hiding places, absence of demarcation between public and private space, poor lighting and favourable
landscaping.
The organization should recognize the potential crime and security risk in dwellings through a risk
assessment process which consists of risk identification, analysis and evaluation. The outcome of this
assessment should then be counterbalanced by specific physical security measures combined with real or
symbolic design elements.
To mitigate the risk of crimes occurring in dwellings, the organization should remove one or more of the
factors shown in Figure 2.
Figure 2 — Crime and security risk in the residential environment
5 Key considerations for residential facilities’ CPTED
The organization should assist designers, planners, estate managers and other stakeholders in CPTED
security to:
— define the protection measures most appropriate to the site;
— influence decisions relating to building design, the layout of the site, landscaping, and other related details
in order to make dwellings attractive and safe for inhabitants and unattractive targets for potential
offenders.
In residential areas with either individual dwellings or residential blocks, the purpose is not only to protect
properties against burglary but also to prevent access by unwanted visitors, the illegal appropriation of
space, degradation of the environment and to mitigate fear of crime.
The organization should consider the design of the built environment that can also influence individual
perceptions of fear of crime, which can exceed the real risk level.
The organization should mandate CPTED as a standard component of design, as part of a continual
improvement process for residential facilities, by enforcing community, site and building security, and
enhancing the safety and quality of life of residents.
The continual improvement process should involve all relevant interested parties by following the risk
management framework given in ISO 31000:2018 to integrate risk management into CPTED activities for
residential facilities.
6 CPTED strategies for residential facilities
6.1 General
CPTED for residential facilities is based on the six key physical concepts described in ISO 22341:2021, B.1.2
to B.1.7. Surveillance and access control incorporate natural, mechanical and organized strategies into
human activities and space design.

The organization should employ the 19 phased CPTED strategies listed in ISO 22341:2021, Table 1, for
residential facilities, with the consideration of the hierarchy of the residential spaces illustrated in Figure 3.
6.2 CPTED concepts for residential facilities
6.2.1 Surveillance
The organization should consider lighting, landscaping and planting, and a closed-circuit television (CCTV)
system to improve surveillance in dwellings.
The organization should:
— ensure 24 h lighting to communal parts of blocks of flats, such as the communal entrance hall, lobbies,
landings, corridors, stairwells, underground garaging facilities and all entrance and exit points, but can
consider dimmed lighting during hours of low occupation to save energy;
— consider environmentally sustainable and security advantage lighting options (e.g. design solutions
promoting natural lighting; the use of good quality lighting, smart dimming sensors and other energy
effective light sources);
— comply with relevant security lighting standards (e.g. ISO/CIE 8995-3:2018), if available or required;
— consider the uniformity of illuminance and colour rendering of lighting for the residential environment
in order to identify people and vehicle number plates without difficulty;
— ensure that the face of users can be easily recognized at a distance (e.g. of 15 m) by proper lighting;
— consider luminaires to be vandal resistant, if necessary;
— ensure that lighting is mounted over a certain height (e.g. 2,5 m) from the ground, so that it is out of reach
for those wishing to cause interference;
— consider floodlighting facades and open areas with trees and gardens, to be decorative while improving
security;
— consider sensor-triggered security lighting to prevent intrusion in isolated or vulnerable spaces, such as
open areas within the boundary of the private spaces e.g. side yard, back yard or roof top;
— ensure that planting design takes full account of the effects of seasonal variations when planning such
planting schemes and all other opportunities of crime;
— ensure that planting does not impede the wayfinding;
— consider defensive planting (e.g. spiny or thorny shrubs, climbing plants to cover walls) to help prevent
graffiti and loitering, and to create or enhance perimeter security;
— consider climbing plants to be used to cover walls to deter graffiti;
— avoid vegetation or shrubs which can provide cover for suspects (e.g. the creation of potential hiding
places);
— avoid uncontrolled planting and branches which can hinder natural surveillance and CCTV coverage, and
impact the performance of lighting nearby;
— consider the position of trees, or other design elements, that can become climbing aids into property;
— consider the position of trees, or other elements that can obscure lights and compromise the visibility of
relevant signs or CCTV cameras;

— ensure that shrubs have a mature growth height (e.g. shrubs no higher than 1 m, branches no lower than
2 m, allowing a 1 m clear field of vision).
When using defensive plants, consideration should be given to traffic flows, and routes of residents and
children, to prevent injury from the thorns.
— consider live monitoring of video surveillance in the restricted control room, to detect potentially
dangerous situations at all times and to react to an emergency if necessary;
— consider using video surveillance to capture an identifiable facial image and personal characteristics as
a basic necessity to reduce vulnerabilities in the area of the dwellings, including attempted entry, graffiti
or other damage;
— consider the specifications, selection, planning, installation, networking, maintaining, operating,
monitoring and testing of security camera systems for the dwelling units;
— ensure that the CCTV system has appropriate signage;
NOTE Legal requirements can apply.
— install CCTV signage to be easily identifiable and have prominent colours.
Video surveillance should not be invasive and should be used for the prevention of crime and enforcement of
residential security.
Caution should be taken:
— when using climbing plants for walls as they can give rise to other problems, such as fire, insects and
building damage;
— so that evacuation equipment (e.g. fire escape ladder) is not misused as climbing aids;
— when planning residential facilities for CPTED, ensuring that universal design and vulnerable persons
are considered.
6.2.2 Access control, site/target hardening and territorial reinforcement
The organization should consider access control and territorial reinforcement to detect, deny and delay
access to potential criminal targets and to discourage the presence of illegitimate users and visitors in the
residential spaces. Relevant safe
...