ISO 14520-17:2022

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 14520-17
ISO/TC 21/SC 8
Gaseous fire-extinguishing systems —
Secretariat: SA
Physical properties and system
Voting begins on:
2021-11-11 design —
Voting terminates on:
Part 17:
2022-01-06
Halocarbon Blend 55
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Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 14520-17:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
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NATIONAL REGULATIONS. © ISO 2021

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ISO/FDIS 14520-17:2021(E)
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© ISO 2021
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ISO/FDIS 14520-17:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Characteristics and uses. 1
4.1 General . 1
4.2 Use of Halocarbon Blend 55 . 2
5 Safety of personnel .4
6 System design . 5
6.1 Fill density . 5
6.2 Superpressurization . 5
6.3 Extinguishant quantity . 5
6.4 Other fill density and superpressurization levels . 8
7 Environmental properties . .8
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ISO/FDIS 14520-17:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
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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).
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www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 21, Equipment for fire protection and
firefighting, Subcommittee SC 8, Gaseous media and firefighting systems using gas.
A list of all parts in the ISO 14520 series can be found on the ISO website.
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.
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ISO/FDIS 14520-17:2021(E)
Introduction
The ISO 14520 series consists of the following parts, under the general title Gaseous fire-extinguishing
systems — Physical properties and system design:
— Part 1: General requirements
— Part 2: Withdrawn
— Part 3: Withdrawn
— Part 4: Withdrawn
— Part 5: FK-5-1-12 extinguishant
— Part 6: Withdrawn
— Part 7: Withdrawn
— Part 8: HFC 125 extinguishant
— Part 9: HFC 227ea extinguishant
— Part 10: HFC 23 extinguishant
— Part 11: HFC 236fa extinguishant
— Part 12: IG-01 extinguishant
— Part 13: IG-100 extinguishant
— Part 14: IG-55 extinguishant
— Part 15: IG-541 extinguishant
— Part 16: Withdrawn
— Part 17 (this document): Halocarbon Blend 55
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 14520-17:2021(E)
Gaseous fire-extinguishing systems — Physical properties
and system design —
Part 17:
Halocarbon Blend 55
1 Scope
This document provides specific requirements for gaseous fire-extinguishing systems with respect to
the Halocarbon Blend 55 extinguishant. It includes details of physical properties, specification, usage
and safety aspects. It also covers systems operating at nominal pressures of 25 bar, 35 bar and 42 bar,
superpressurized with nitrogen. This document does not preclude the use of other systems.
5 2
NOTE 1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .
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 14520-1:2015, 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 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/
4 Characteristics and uses
4.1 General
Extinguishant Halocarbon Blend 55 shall comply with the specifications shown in Table 1.
Halocarbon Blend 55 [blend of 50 ± 3 % HFO-1233zd(E) and 50 ± 3 % FK-5-1-12 (by mass)] is a colourless,
almost odourless, electrically non-conductive gas, with a density approximately 6,38 times that of air.
Its physical properties are shown in Table 2.
Halocarbon Blend 55 extinguishes fires mainly by physical means, but also by some chemical means.
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ISO/FDIS 14520-17:2021(E)
Table 1 — Specifications for Halocarbon Blend 55
Property Requirement
Purity 99,5 % by mass, min.
−4
Acidity 3 × 10 % by mass, max.
−4
Water content 10 × 10 % by mass, max.
−4
Non-volatile residue 300 × 10 % by mass, max.
Suspended matter or sediment None visible
a
Kinetic dimers of HFP < 5 600 mg/kg
b
Thermodynamic dimer of HFP + HF adduct < 190 mg/kg
a
Kinetic dimers of HFP (CAS 2070-70-4).
b
Thermodynamic dimer of HFP (CAS 1584-03-8) + its HF adduct (CAS 30320-28-6).
Table 2 — Physical properties of Halocarbon Blend 55
Property Units Value
Molecular mass — 184,72
Boiling point at 1,013 bar (absolute) °C 20,7
Freezing point °C -107
Critical temperature °C 159,2
Critical pressure bar (absolute) 28,92
3
Criti
...