ISO/IEC TS 22237-6:2018

Information technology - Data centre facilities and infrastructures - Part 6: Security systems

This document addresses the physical security of data centres based upon the criteria and classifications for "availability", "security" and "energy efficiency enablement" within ISO/IEC TS 22237‑1. This document provides designations for the data centre spaces defined in ISO/IEC TS 22237‑1. This document specifies requirements and recommendations for those data centre spaces, and the systems employed within those spaces, in relation to protection against: a) unauthorized access addressing constructional, organizational and technological solutions; b) fire events igniting within data centre spaces; c) other events within or outside the data centre spaces, which would affect the defined level of protection. Safety and electromagnetic compatibility (EMC) requirements are outside the scope of this document and are covered by other standards and regulations. However, information given in this document may be of assistance in meeting these standards and regulations.

Technologie de l’information — Installation et infrastructures de centres de traitement de données — Partie 6: Systèmes de sécurité

General Information

• Status: Withdrawn
• Publication Date: 26-Apr-2018
• ICS: 35.020 - Information technology (IT) in general
• Technical Committee: ISO/IEC JTC 1/SC 39 - Sustainability, IT and data centres
• Drafting Committee: ISO/IEC JTC 1/SC 39/WG 3 - Sustainable facilities and infrastructures
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 19-Feb-2024
• Completion Date: 30-Oct-2025

Relations

• Revised: ISO/IEC 22237-6:2024 - Information technology - Data centre facilities and infrastructures - Part 6: Security systems
• Effective Date: 06-Jun-2022

Standards Content (Sample)

TECHNICAL ISO/IEC TS
SPECIFICATION 22237-6
First edition
2018-05
Information technology — Data centre
facilities and infrastructures —
Part 6:
Security systems
Technologie de l’information — Installation et infrastructures de
centres de traitement de données —
Partie 6: Systèmes de sécurité
Reference number
©
ISO/IEC 2018
© ISO/IEC 2018
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
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below or ISO’s member body in the country of the requester.
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Published in Switzerland
ii © ISO/IEC 2018 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 2
3.1 Terms and definitions . 2
3.2 Abbreviated terms . 3
4 Conformance . 3
5 Physical security . 3
5.1 General . 3
5.2 Risk assessment . 4
5.3 Designation of data centre spaces — Protection Classes . 5
6 Protection Class against unauthorized access . 5
6.1 General . 5
6.2 Implementation . 8
6.2.1 General. 8
6.2.2 Access to the data centre premises .10
6.2.3 Protection Class 1 .12
6.2.4 Protection Class 2 .13
6.2.5 Protection Class 3 .14
6.2.6 Protection Class 4 .16
6.2.7 Cabinets and arrangement of cabinets .17
7 Protection Class against fire events igniting within data centre spaces .17
7.1 General .17
7.1.1 Protection Classes .17
7.1.2 Fire compartments and barriers .18
7.1.3 Fire detection and fire alarm systems .19
7.1.4 Fixed firefighting systems .19
7.1.5 Portable firefighting equipment .20
7.1.6 Structural considerations .21
7.2 Implementation of Protection Class requirements .21
7.2.1 Protection Class 1 .21
7.2.2 Protection Class 2 .21
7.2.3 Protection Classes 3 and 4 .21
8 Protection Class against environmental events (other than fire) within data centre
spaces .22
8.1 Protection Classes .22
8.2 Implementation .22
8.2.1 General.22
8.2.2 Protection Class 1 .23
8.2.3 Protection Class 2 .23
8.2.4 Protection Class 3 .23
8.2.5 Protection Class 4 .24
9 Protection Class against environmental events outside the data centre spaces .24
9.1 Protection Classes .24
9.2 Implementation .24
9.2.1 General.24
9.2.2 Protection Class 1 .25
9.2.3 Protection Class 2 .25
9.2.4 Protection Class 3 .25
9.2.5 Protection Class 4 .25
© ISO/IEC 2018 – All rights reserved iii

10 Systems to prevent unauthorized access .25
10.1 General .25
10.2 Technology .26
10.2.1 Security lighting.26
10.2.2 Video surveillance systems .26
10.2.3 Intruder and holdup alarm systems .27
10.2.4 Access control .27
10.2.5 Alarm monitoring . .27
Annex A (informative) Pressure relief: Additional information .28
Bibliography .30
iv © ISO/IEC 2018 – All rights reserved

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work. In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1.
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 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on 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 the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 39, Sustainability for and by Information Technology.
A list of all parts in the ISO/IEC TS 22237 series can be found on the ISO website.
© ISO/IEC 2018 – All rights reserved v

Introduction
The unrestricted access to internet-based information demanded by the information society has led to
an exponential growth of both internet traffic and the volume of stored/retrieved data. Data centres
are housing and supporting the information technology and network telecommunications equipment
for data processing, data storage and data transport. They are required both by network operators
(delivering those services to customer premises) and by enterprises within those customer premises.
Data centres need to provide modular, scalable and flexible facilities and infrastructures to easily
accommodate the rapidly changing requirements of the market. In addition, energy consumption of data
centres has become critical both from an environmental point of view (reduction of carbon footprint)
and with respect to economical considerations (cost of energy) for the data centre operator.
The implementation of data centres varies in terms of:
a) purpose (enterprise, co-location, co-hosting, or network operator);
b) security level;
c) physical size;
d) accommodation (mobile, temporary and permanent constructions).
The needs of data centres also vary in terms of availability of service, the provision of security and
the objectives for energy efficiency. These needs and objectives influence the design of data centres
in terms of building construction, power distribution, environmental control and physical security.
Effective management and operational information is required to monitor achievement of the defined
needs and objectives.
The ISO/IEC TS 22237 series specifies requirements and recommendations to support the various
parties involved in the design, planning, procurement, integration, installation, operation and
maintenance of facilities and infrastructures within data centres. These parties include:
1) owners, facility managers, ICT managers, project managers, main contractors;
2) architects, consultants, building designers and builders, system and installation designers;
3) facility and infrastructure integrators, suppliers of equipment;
4) installers, maintainers.
At the time of publication of this document, the ISO/IEC TS 22237 series will comprise the following
documents:
ISO/IEC TS 22237-1, Information technology — Data centre facilities and infrastructures — Part 1: General
concepts;
ISO/IEC TS 22237-2, Information technology — Data centre facilities and infrastructures — Part 2:
Building construction;
ISO/IEC TS 22237-3, Information technology — Data centre facilities and infrastructures — Part 3: Power
distribution;
ISO/IEC TS 22237-4, Information technology — Data centre facilities and infrastructures — Part 4:
Environmental control;
ISO/IEC TS 22237-5, Information technology — Data centre facilities and infrastructures — Part 5:
Telecommunications cabling infrastructure;
ISO/IEC TS 22237-6, Information technology — Data centre facilities and infrastructures — Part 6:
Security systems;
vi © ISO/IEC 2018 – All rights reserved

ISO/IEC TS 22237-7, Information technology — Data centre facilities and infrastructures — Part 7:
Management and operational information;
The inter-relationship of the specifications within the ISO/IEC TS 22237 series is shown in Figure 1.
Figure 1 — Schematic relationship between the ISO/IEC TS 22237 series of documents
ISO/IEC TS 22237-2 to ISO/IEC TS 22237-6 specify requirements and recommendations for particular
facilities and infrastructures to support the relevant classification for “availability”, “physical security”
and “energy efficiency enablement” selected from EN 50600-1.
This document, addresses the physical security of facilities and infrastructure within data centres
together with the interfaces for monitoring the performance of those facilities and infrastructures in
line with ISO/IEC TS 22237-7 (in accordance with the requirements of ISO/IEC TS 22237-1).
ISO/IEC TS 22237-7 addresses the operational and management information (in accordance with the
requirements of ISO/IEC TS 22237-1.
This document is intended for use by and collaboration between architects, building designers and
builders, system and installation designers and security managers among others.
The ISO/IEC TS 22237 series does not address the selection of information technology and network
telecommunications equipment, software and associated configuration issues.
© ISO/IEC 2018 – All rights reserved vii

TECHNICAL SPECIFICATION ISO/IEC TS 22237-6:2018(E)
Information technology — Data centre facilities and
infrastructures —
Part 6:
Security systems
1 Scope
This document addresses the physical security of data centres based upon the criteria and classifications
for “availability”, “security” and “energy efficiency enablement” within ISO/IEC TS 22237-1.
This document provides designations for the data centre spaces defined in ISO/IEC TS 22237-1.
This document specifies requirements and recommendations for those data centre spaces, and the
systems employed within those spaces, in relation to protection against:
a) unauthorized access addressing constructional, organizational and technological solutions;
b) fire events igniting within data centre spaces;
c) other events within or outside the data centre spaces, which would affect the defined level of
protection.
Safety and electromagnetic compatibility (EMC) requirements are outside the scope of this document
and are covered by other standards and regulations. However, information given in this document may
be of assistance in meeting these standards and regulations.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC TS 22237-1, Information technology — Data centre facilities and infrastructures — Part 1: General
concepts
ISO/IEC TS 22237-2:2018, Information technology — Data centre facilities and infrastructures — Part 2:
Building construction
ISO/IEC TS 22237-3, Information technology — Data centre facilities and infrastructures — Part 3: Power
distribution
ISO/IEC TS 22237-4, Information technology — Data centre facilities and infrastructures — Part 4:
Environmental control
ISO/IEC TS 22237-5, Information technology — Data centre facilities and infrastructures — Part 5:
Telecommunications cabling infrastructure
IEC 60839-11-1, Alarm and electronic security systems — Part 11-1: Electronic access control systems —
System and components requirements
IEC 62676-1-1:2014, Video surveillance systems for use in security applications — Part 1-1: System
requirements — General
EN 3 (all parts), Portable fire extinguishers
© ISO/IEC 2018 – All rights reserved 1

EN 54 (all parts), Fire detection and fire alarm systems
EN 54-13, Fire detection and fire alarm systems — Part 13: Compatibility assessment of system components
EN 54-20:2006, Fire detection and fire alarm systems — Part 20: Aspirating smoke detectors
EN 1047-2, Secure storage units — Classification and methods of test for resistance to fire — Part 2: Data
rooms and data container
EN 1366-3, Fire resistance tests for service installations — Part 3: Penetration seals
EN 1627:2011, Pedestrian doorsets, windows, curtain walling, grilles and shutters — Burglar resistance —
Requirements and classification
EN 1634 (all parts), Fire resistance and smoke control tests for door and shutter assemblies, openable
windows and elements of building hardware
EN 12845, Fixed firefighting systems — Automatic sprinkler systems — Design, installation and
maintenance
EN 13565-2, Fixed firefighting systems — Foam systems — Part 2: Design, construction and maintenance
CEN/TS 14816, Fixed firefighting systems — Water spray systems — Design, installation and maintenance
CEN/TS 14972, Fixed firefighting systems — Watermist systems — Design and installation
EN 16750, Fixed firefighting systems — Oxygen reduction systems — Design, installation, planning and
maintenance
EN 50131 (all parts), Alarm systems — Intrusion and hold-up systems
EN 50136 (all parts), Alarm systems — Alarm transmission systems and equipment
EN 50518 (all parts), Monitoring and alarm receiving centre
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC TS 22237-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at https: //www .iso .org/obp
3.1.1
forcible threat
threat exhibited by physical force
3.1.2
hold time
time during which a concentration of fire extinguishant is maintained at an effective level with the
space being protected
3.1.3
information technology equipment
equipment providing data storage, processing and transport services together with equipment
dedicated to providing direct connection to core and/or access networks
2 © ISO/IEC 2018 – All rights reserved

3.1.4
residual risk
remaining risk(s) posed to the data centre assets requiring protection following the deployment of
appropriate countermeasures
3.1.5
security manager
individual with overall responsible for all operational security aspects of the data centre, including
logical and physical control mechanisms or processes
3.1.6
surreptitious attack
compromise of an asset via logical or physical means with the objective that the attack remains
undetected
3.1.7
surreptitious threat
threat of a surreptitious attack by entities via logical or physical means leading to the compromise of
that asset
3.2 Abbreviated terms
For the purposes of this document, the abbreviated terms given in ISO/IEC TS 22237-1 and the
following apply.
I&HAS intruder and holdup alarm systems
VSS video surveillance system
4 Conformance
For a data centre to conform to this document:
1) the required Protection Class of Clause 5 shall be applied to each of the spaces of the data centre;
2) the requirements of the relevant Protection Class of Clauses 6, 7, 8 and 9 shall be applied;
3) the systems to support the requirements of Clause 6 shall be in accordance with Clause 10;
4) local regulations, including safety, shall be met.
5 Physical security
5.1 General
The degree of physical security applied to the facilities and infrastructures of a data centre has an
influence on both the availability of function of, and the integrity/security of the data stored and
processed within, the data centre.
5.3 provides minimum requirements for the data centres spaces defined in ISO/IEC TS 22237-1. The
requirements and recommendations for those data centre spaces, and the systems employed within
those spaces, address protection against:
a) unauthorized access (see Clause 6);
b) fire events originating within data centres spaces (Clause 7);
c) other events within (see Clause 8) or outside (see Clause 9) the data centre spaces, which would
affect the defined level of protection.
© ISO/IEC 2018 – All rights reserved 3

Constructional requirements for walls and penetrations are provided in ISO/IEC TS 22237-2 and
relevant cross-references are provided from this document.
In order for a space within the data centre to be considered to be of a given Protection Class the
architectural and engineering design of the space (or entry to that space) shall meet or exceed that
Protection Class for all aspects detailed above.
5.2 Risk assessment
The requirements for operational security should be determined by the organization responsible for
data centre assets. The requirements should be determined following a risk assessment based on
the threats posed to the data, and the “classification” of that data. See ISO/IEC TS 22237-1 for further
information regarding risk assessment methodologies.
Figure 2 illustrates the concept of the risk assessment which is described as follows:
a) asset value: the classification of the material should be determined at an early stage, so that is
possible to deploy appropriate protection countermeasures. The nature of the “classification”
maybe “native”, or “raised” due to the effects of data aggregation;
b) likelihood: the probability of some form of attack against the protected assets;
c) threat (forcible or surreptitious) analysis: for example, posed by unauthorized access to the assets
resulting in loss or unavailability of the assets;
d) vulnerability analysis: for example, inadequate physical security or technical controls of the
hosted data.
Figure 2 — Risk assessment concepts
These four items are analysed during the risk assessment process, to identify the baseline risk posed to
the data centre. Management of the identified baseline risk employs appropriate technical, physical and
procedural countermeasures or a combination thereof.
Following the deployment of baseline countermeasures, further decisions shall be taken relating to the
residual risk(s) as follows, driven by the acceptance of risk of the asset owner:
1) toleration — the remaining risk(s) are accepted and no additional countermeasures deployed;
2) treatment — additional measures are deployed to counter the remaining risk(s);
3) transferral — the risk(s) are transferred to another party, for example obtaining additional
insurance cover the mitigate the risk(s);
4) termination — the activity posing the risk is terminated.
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5.3 Designation of data centre spaces — Protection Classes
Each of the data centre spaces, independent of the size or purpose of the data centre, is designated as
being of a particular Protection Class. There is no concept of a data centre of a given Protection Class.
The requirements for the Protection Class to be applied to the elements of the following facilities and
infrastructures within the data centre are defined in:
a) ISO/IEC TS 22237-3 for the power distribution system;
b) ISO/IEC TS 22237-4 for the environmental control system.
All telecommunications equipment and connections to the telecommunications cabling infrastructure
shall be in areas of Protection Class 3. Where pathways containing telecommunication cabling are
routed in areas of a lower Protection Class they shall be monitored for unauthorized access.
In addition, the risk assessment of 5.2 together with the construction and configuration of the data
centre described in 6.2 will require other spaces to be defined in terms of Protection Class. An example
of this is shown in Table 1.
Table 1 — Examples of Protection Classes for data centre spaces
Protection Class 1 Protection Class 2 Protection Class 3 Protection Class 4
Personnel entrances to The internal access to Premises entrance facil- Cabinets, cages or rows of
a,b
buildings or structures docking bays (the barrier ity cabinets within the com-
containing data centre of the docking bay provid- puter room space
Building entrance facili-
spaces ing the interface between
b
ties
Protection Classes 1 and 2)
Computer room spaces
External premises securi-
ty spaces Control room space
Personnel entrances to the Data centre security spaces
data centre spaces
Storage spaces
Holding spaces
Testing spaces
Data centre office spaces
a
This applies to premises entrance facilities which are within the control of the data centre.
b
Access restrictions apply to pathways leading to areas of Protection Classes of a lower Protection Class.
6 Protection Class against unauthorized access
6.1 General
This document applies the four Protection Classes in relation to access to spaces accommodating the
elements of the different facilities and infrastructures as detailed in Table 2 (in accordance with ISO/
IEC TS 22237-1).
© ISO/IEC 2018 – All rights reserved 5

Table 2 — Protection Classes against unauthorized access
Type of protection Class 1 Class 2 Class 3 Class 4
Protection against Public or semi-pub- Area that is accessi- Area restricted to Area restricted to
unauthorized access lic area. ble to all authorized specified employees specified employees
personnel (employ- and visitors (other who have an identi-
ees and visitors). personnel with ac- fied need to have ac-
cess to Class 2 shall cess (other personnel
be accompanied by with access to Class
personnel author- 2 or 3 areas shall be
ized to access Class accompanied by per-
3 areas). sonnel authorized to
access Class 4 areas).
The Protection Classes feature increasing levels of access control. The areas of the data centre requiring
the greatest physical protection against unauthorized access will be accommodated in spaces with the
highest Protection Class. Further guidance can be found in the IEC 60839-11 series.
It should not be assumed that:
a) all areas of a given Protection Class are accessible to persons having access to an area of that
Protection Class;
b) persons having access to an area of that Protection Class have access to all areas of a lower
Protection Class.
This clause defines the rules for implementing such Classes.
The access to spaces and systems shall be limited to the inevitable necessary operative minimum.
This applies to the aspects of spaces, time, personnel and knowledge. The implementation of physical
security shall be effected according to the philosophy shown schematically in Figure 3, referred to as
the “Onion Skin” or “Defence in Depth” approach/model.
Figure 3 — Protection Classes within the 4-layer physical protection model
In order to be applicable to more general implementations of data centres, the simplistic model of
Figure 3 may be visualized as series Protection Class islands as shown in Figure 4.
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Figure 4 — Protection Class islands
5.3 provides examples of the Protection Classes applied to data centre spaces but the technological
solutions to the control of unauthorized access vary across the particular data centre spaces within a
Protection Class.
All elements of the border/barrier of an area with a given Protection Class shall have the same level of
resistance to unauthorized access. Where the data centre infrastructures specified in ISO/IEC TS 22237-
2 to ISO/IEC TS 22237-6 cross boundaries from one Protection Class to another they shall be provided
with protection suitable to the highest Protection Class interconnected as shown in Figure 5.
NOTE National or local regulations can prevent security measures being applied to pathways (e.g.
maintenance holes, etc.) for infrastructures external to the premises.
Figure 5 — Interconnection between Protection Class islands
Access control systems of a given Protection Class shall be managed from areas with the same or higher
Protection Class.
Pathways of the data centre infrastructures (e.g. power supply, environmental control and
telecommunications cabling) shall be designed to prevent unauthorized passage between areas of
different Protection Class.
Data centres and their complementary functions of technical infrastructure shall be organized in areas
which mirror the needs of security, safety and availability of the data centre which match the assumed
risks and protection goals.
© ISO/IEC 2018 – All rights reserved 7

The risk bearing elements of the data centre should be located as far from the public or other
unauthorized personnel as possible. Where this is not practicable, additional protection measures may
be required as determined by the output of the risk assessment process or the site security assessment.
6.2 Implementation
6.2.1 General
The barrier defining Protection Class 1 is the outer perimeter of the premises containing the data
centre. The facilities and infrastructures of the data centre may be accommodated in part or all of
a single building or structure within the premises or may be distributed across several buildings or
structures.
If the premises enable full and unrestricted public access to the boundaries of the building(s) or other
structures, the exterior walls (or other defined internal barrier) of the building(s)/structures(s)
represent the boundary of Protection Class 1. In such a case, as shown in the example of Figure 6:
a) the boundary of Protection Class 2 would represent the barrier between any entrances of buildings
or structures comprising the premises and the areas comprising the data centre and its associated
spaces (these spaces may be in separate buildings or structures of Protection Class 1);
b) the boundary of Protection Class 3 would represent the barrier between the entrance to the
designated data centre space and the area requiring Protection Class 3;
c) the boundary of Protection Class 4 would represent the barrier between the entrance to the area
requiring Protection Class 3 and the area requiring Protection Class 4;
d) the Protection Class system operates horizontally and vertically (e.g. risers, lift shafts, stair
wells, atriums, light-wells) for the buildings and structures i.e. if the roof-top is considered to
be of Protection Class 1, appropriate barriers will be required to any roof-top structures which
accommodate facilities or infrastructure requiring a higher Protection Class.
Figure 6 — Example of Protection Classes applied to data centre premises without external
barriers
If the premises are provided with an external physical barrier that provides a demarcation of Protection
Class 1 then, as shown in the example of Figure 7:
1) the number of penetrations of the boundary of Protection Class 1 for personnel and vehicular
access shall be minimized;
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2) the boundary of Protection Class 2 would represent the exterior walls and associated entrances of
the buildings and other structures comprising the data centre and its associated spaces;
3) the boundary of Protection Class 3 would represent the barrier between any entrances of buildings
or structures comprising the premises and the areas comprising the data centre and its associated
spaces (these spaces may be in separate buildings or structures of Protection Class 2);
4) the boundary of Protection Class 4 would represent the barrier between the entrance to the
designated data centre space and the area requiring Protection Class 4;
5) the Protection Class system operates horizontally and vertically (e.g. risers, lift shafts, stair
wells, atriums, light-wells) for the buildings and structures i.e. if the roof-top is considered to
be of Protection Class 2, appropriate barriers will be required to any roof-top structures which
accommodate facilities or infrastructure requiring a higher Protection Class;
This only applies in relation to protection against unauthorized access. For the purposes of
protection against external environmental events a roof-top is considered to be a Protection Class
1 boundary only and any roof-top structures require additional protection.
Figure 7 — Example of Protection Classes applied to data centre premises with external
barriers
In Figure 7, the buildings/structures shown may be dedicated to specific spaces serving the various
data centre infrastructures e.g. generator space or transformer space. Each building/structure shall
apply appropriate barriers to protect the relevant infrastructure element. In addition, the barriers may
be required to provide visual and acoustic screening.
As described above, roof-tops may be considered Protection Class 1 or 2, depending on the configuration
of the premises containing the data centre. Any openings in roof-tops shall be protected in accordance
with the Protection Class of the space immediately below the opening. In addition, any roof-top
structures dedicated to specific spaces serving the various data centre infrastructures shall apply
appropriate barriers to protect the relevant infrastructure element.
Any access routes to the roof, for purposes of maintenance and repair of the roof, roof-top structures
and, where relevant, to infrastructure elements, shall be within areas of Protection Class equal to or
higher than that of the roof-top.
The requirements for the barriers between areas of different Protection Class in relation to protection
against unauthorized access are not based on their physical construction i.e. they may be fences, exterior
© ISO/IEC 2018 – All rights reserved 9

or interior walls of buildings together with doors and other penetrations fitted with appropriate
systems (see Clause 10).
Any access points to spaces of a given Protection Class that are dedicated to a particular facility or
infrastructure shall not provide an access route to general data centre spaces, or spaces which are
dedicated to other facilities or infrastructures, of either the same or higher protection Class.
The combination of resistance offered by the boundaries of each Protection Class together with the
monitoring of those boundaries shall present a person attempting unauthorized access by means of
forcible threats with increasingly difficult challenges. The materials comprising those barriers shall be
considered in terms of:
— the tools and equipment against which they are proven to provide resistance;
— the time required to penetrate those barriers using those tools and equipment.
Any surveillance and monitoring equipment shall take the penetration times into account. The
requirements for access control systems which allow persons to cross the boundaries are described in
Clause 10.
When a building houses more than the data centre, each boundary which is shared with external
parties shall be considered as an external wall, i.e. a boundary of Protection Class 1. Any boundary
which is shared with an adjacent building, not part of the data centre, shall be considered as an external
wall, i.e. a boundary of Protection Class 1.
6.2.2 Access to the data centre premises
6.2.2.1 General
6.2.2.1.1 Requirements
Access routes shall be clearly signed to segregate employees, visitors and deliveries to the data centre.
Plans shall exist which address operation in situations where the primary access routes are unavailable.
6.2.2.1.2 Recommendations
Consideration should be given to any requirements for:
a) enhanced lighting on access approach routes;
b) hostile vehicle mitigation on data centre approach routes;
c) fences and other boundary controls;
d) sterile zones for the management and handling of visitors or deliveries;
e) secondary access route, in case the primary route becomes unavailable.
6.2.2.2 Parking
6.2.2.2.1 Requirements
The requirements of a given Protection Class address vehicular access to the premises containing the
data centre.
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The outcome of a risk analysis, taking into account the security requirements of the site and the
importance of the data involved, may place restrictions upon:
a) the designated location, and minimum distance from the data centre spaces, of any parking areas
for visitors and unauthorized vehicles;
b) the designated location, and minimum distance from the data centre spaces, of any parking areas
for employees;
c) the designated location, and minimum distance from the data centre spaces, of any parking areas
for delivery vehicles;
d) the designated location, and minimum distance from the data centre spaces, of any parking areas
for maintenance and emergency vehicles.
6.2.2.2.2 Recommendations
Consideration should be given to:
a) video surveillance system (VSS) monitoring of the parking area;
b) location of the vehicle parking outside of the data centre perimeter;
c) lighting requirements;
d) vehicle searching requirements;
e) passage of vehicle occupants from the parking location to the data centre, including access control
requirements;
f) operational security process requirements.
6.2.2.3 Visitors
6.2.2.3.1 Requirements
Suitable space shall be allocated for the processing of visitors.
6.2.2.3.2 Recommendations
Any doors leading to the data centre spaces should have appropriate door mechanisms in place to
provide access to authorized personnel and authorized visitors only. The use of anti-passback door
controls should be considered based upon either the overall security requirements of the data centre or
to meet operational requirements.
Consideration should be given to VSS monitoring of the visitor access.
6.2.2.4 Deliveries
6.2.2.4.1 Requirements
Movement of goods and personnel from the loading bay to other data centre spaces shall be controlled
by appropriate security mechanisms (e.g. interlocks) applied at the inner boundary of the loading bay.
© ISO/IEC 2018 – All rights reserved 11

To accommodate deliveries in data
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