ISO 14520-2:2016

INTERNATIONAL ISO
STANDARD 14520-2
Third edition
2016-10-01
Gaseous fire-extinguishing systems —
Physical properties and system
design —
Part 2:
CF I extinguishant
Systèmes d’extinction d’incendie utilisant des agents gazeux —
Propriétés physiques et conception des systèmes —
Partie 2: Agent extincteur CF I
Reference number
©
ISO 2016
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, 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 the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative reference . 1
3 Terms and definitions . 1
4 Characteristics and uses . 1
4.1 General . 1
4.2 Use of CF I systems . 2
5 Safety of personnel . 4
6 System design . 5
6.1 Fill density. 5
6.2 Superpressurization . 5
6.3 Extinguishant quantity . 5
7 Environmental properties . 6
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 documents 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 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 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.
The committee responsible for this document is ISO/TC 21, Equipment for fire protection and fire fighting,
Subcommittee SC 8, Gaseous media and firefighting systems using gas.
This third edition cancels and replaces the second edition (ISO 14520-2:2006), which has been
technically revised with the following changes:
— added Clause 7.
A list of all parts in the ISO 14520 series can be found on the ISO website.
iv © ISO 2016 – All rights reserved

INTERNATIONAL STANDARD ISO 14520-2:2016(E)
Gaseous fire-extinguishing systems — Physical properties
and system design —
Part 2:
CF I extinguishant
1 Scope
This document contains specific requirements for gaseous fire-extinguishing systems, with respect to
the CF I extinguishant. It includes details of physical properties, specification, usage and safety aspects.
This document covers systems operating at a nominal pressure of 25 bar. This does not preclude the
use of other systems.
2 Normative reference
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 14520-1, Gaseous fire-extinguishing systems — Physical properties and system design — Part 1:
General requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14520-1 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 http://www.iso.org/obp
4 Characteristics and uses
4.1 General
Extinguishant CF I shall comply with the specification shown in Table 1.
CF I is a colourless, almost odourless, electrically non-conductive gas with a density approximately
seven times that of air.
The physical properties are shown in Table 2.
CF I extinguishes fires mainly by chemical means, but also by some physical means.
Table 1 — Specification for CF I
Property Requirement
Purity 99,9 % by mass, min.
−6
Acidity 1 × 10 by mass, max.
−6
Water content 6 × 10 by mass, max.
−6
Non-volatile residue 100 × 10 by mass, max.
Suspended matter or sediment None visible
Table 2 — Physical properties of CF I
Property Units Value
Molecular mass — 195,9
Boiling point at 1,013 bar (absolute) °C −22,5
Freezing point °C − 110
Critical temperature °C 122
Critical pressure bar abs 40,4
Critical volume cm /mol 225,0
Critical density kg/m 871
Vapour pressure, 20 °C bar abs 4,65
Liquid density, 20 °C kg/m 2 096
Saturated vapour density, 20 °C kg/m 8,051
Specific volume of superheated
m /kg 0,112
vapour at 1,013 bar and 20 °C
Chemical formula CF I
Chemical name
Trifluoroiodomethane
4.2 Use of CF I systems
CF I total flooding systems may be used for extinguishing fires of all classes within the limits specified
in ISO 14520-1:2015, Clause 4.
The extinguishant requirements per volume of protected space are shown in Table 3 for various levels
of concentration. These are based on methods shown in ISO 14520-1:2015, 7.6.
The extinguishing concentrations and design concentrations for n-heptane and Surface Class A hazards
are shown in Table 4. Inerting concentrations are shown
...