ISO 14520-5:2024

Gaseous fire-extinguishing systems - Physical properties and system design - Part 5: FK-5-1-12 extinguishant

This document contains specific requirements for gaseous fire-extinguishing systems, with respect to FK-5-1-12 extinguishant. It includes details of physical properties, specifications, usage and safety aspects. This document is applicable only to systems operating at nominal pressures of 25 bar, 34,5 bar, 42 bar and 50 bar[1] with nitrogen propellant. This does not preclude the use of other systems. [1] 1 bar = 0,1 MPa = 105 Pa; 1 MPa = 1 N/mm2.

Systèmes d'extinction d'incendie utilisant des agents gazeux — Propriétés physiques et conception des systèmes — Partie 5: Agent extincteur FK-5-1-12

General Information

• Status: Published
• Publication Date: 07-Jan-2024
• ICS: 13.220.10 - Fire-fighting
• Technical Committee: ISO/TC 21/SC 8 - Gaseous media and firefighting systems using gas
• Drafting Committee: ISO/TC 21/SC 8 - Gaseous media and firefighting systems using gas
• Current Stage: 6060 - International Standard published
• Start Date: 08-Jan-2024
• Due Date: 12-May-2025
• Completion Date: 08-Jan-2024

Relations

• Revises: ISO 14520-5:2019 - Gaseous fire-extinguishing systems - Physical properties and system design - Part 5: FK-5-1-12 extinguishant
• Effective Date: 06-Jun-2022

Overview

ISO 14520-5:2024 - Gaseous fire‑extinguishing systems - Physical properties and system design - Part 5: FK‑5‑1‑12 extinguishant specifies physical, safety and system‑design requirements for using FK‑5‑1‑12 (dodecafluoro‑2‑methylpentan‑3‑one) in gaseous fire‑extinguishing systems. The fourth edition (2024) updates specifications (including dimer limits) and is applicable to total‑flooding systems operating at nominal container pressures of 25, 34.5, 42 and 50 bar using nitrogen propellant. It complements the general requirements in ISO 14520‑1.

Key topics and technical requirements

• Extinguishant specifications: minimum purity 99.0% mol/mol; limits on acidity, water, non‑volatile residue, visible sediment and dimer content.
• Physical properties: molecular mass (316.04), boiling/freezing points, critical temperature/pressure/density, liquid density and vapour data - used for storage, piping and discharge calculations.
• Design concentrations and mass‑per‑volume tables: published m/V values across temperatures (‑20 °C to 100 °C) and concentrations (3–10% by volume), plus reference extinguishing and minimum design concentrations for specific fuels (e.g., n‑heptane extinguishment 4.5% - design 5.9%).
• Fuel‑specific guidance: extinguishment/design concentrations for Class B and Class A fuels (heptane, wood crib, PMMA, PP, ABS), other fuels (acetone, ethanol, methanol, diesel) and inerting concentrations (e.g., methane inerting 8.8% - design 9.7%).
• System design factors: container fill density limits, superpressurization, extinguishant quantity calculations (m = c·V / [(100 − c)·S]), and alternate fill/superpressurization options.
• Safety and toxicology: personnel safety considerations (hazards from the agent, combustion and breakdown products). Toxicological values: 4 h LC50 >10% (rats), NOAEL 10%, LOAEL >10%.
• Environmental properties: dedicated section addressing environmental aspects of FK‑5‑1‑12.

Practical applications

• Design and specification of total‑flooding gaseous suppression systems for sensitive enclosures where water or powder is unsuitable, such as:
  • data centres and server rooms
  • telecommunications equipment rooms
  • museums, archives and cleanrooms
  • engine rooms and control centres
• Use for both extinguishment and inerting applications where precise concentration control is required.

Who should use this standard

• Fire protection engineers and system designers
• Specifiers, manufacturers and installers of gaseous suppression systems
• Risk assessors, safety managers, regulators and insurance assessors
• Compliance teams working with ISO 14520 series requirements

Related standards

• ISO 14520‑1: General requirements for gaseous fire‑extinguishing systems
• Other parts of the ISO 14520 series addressing different extinguishants and test methods

Keywords: ISO 14520‑5:2024, FK‑5‑1‑12, gaseous fire‑extinguishing systems, system design, physical properties, fill density, design concentration, total flooding, nitrogen propellant.

Standards Content (Sample)

International
Standard
ISO 14520-5
Fourth edition
Gaseous fire-extinguishing
2024-01
systems — Physical properties and
system design —
Part 5:
FK-5-1-12 extinguishant
Systèmes d'extinction d'incendie utilisant des agents gazeux —
Propriétés physiques et conception des systèmes —
Partie 5: Agent extincteur FK-5-1-12
Reference number
© 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
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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
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 FK-5-1-12 systems .2
5 Safety of personnel . 5
6 System design . 6
6.1 Fill density .6
6.2 Superpressurization .7
6.3 Extinguishant quantity .7
6.4 Other fill density and superpressurization levels .10
7 Environmental properties . .10
Bibliography .11

iii
Foreword
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The procedures used to develop this document and those intended for its further maintenance are described
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of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
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ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
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Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 21, Equipment for fire protection and fire
fighting, Subcommittee SC 8, Gaseous media and firefighting systems using gas.
This fourth edition cancels and replaces the third edition (ISO 14520-5:2019), which has been technically
revised.
The main changes are as follows:
— new specifications for dimers have been added to Table 1.
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.

iv
International Standard ISO 14520-5:2024(en)
Gaseous fire-extinguishing systems — Physical properties and
system design —
Part 5:
FK-5-1-12 extinguishant
1 Scope
This document contains specific requirements for gaseous fire-extinguishing systems, with respect to FK-5-
1-12 extinguishant. It includes details of physical properties, specifications, usage and safety aspects.
This document is applicable only to systems operating at nominal pressures of 25 bar, 34,5 bar, 42 bar and
1)
50 bar with nitrogen propellant. This does not preclude the use of other systems.
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, 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 FK-5-1-12 shall conform to the specifications shown in Table 1.
FK-5-1-12 is a clear, colourless, almost odourless, electrically non-conductive gas with a density
approximately 11 times that of air.
The physical properties are shown in Table 2.
FK-5-1-12 extinguishes fires mainly by physical means, but also by some chemical means.
5 2
1) 1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .

Table 1 — Specifications for FK-5-1-12
Property Requirement
Purity 99,0 % mol/mol min.
–6
Acidity 3 × 10 by mass, max.
Water content 0,001 % by mass, max.
Non-volatile residue 0,03 % by mass, max.
Suspended matter or sediment None visible
a
Kinetic dimers of HFP <2 850 mg/kg
Thermodynamic dimer of HFP + HF
<95 mg/kg
b
adduct
a
Kinetic dimers of HFP (CAS Registry Number® 2070-70-4). (Chemical Abstracts Service
(CAS) Registry Number® is a trademark of the American Chemical Society (ACS). This
information is given for the convenience of users of this document and does not constitute
an endorsement by ISO of the product named. Equivalent products may be used if they can be
shown to lead to the same results).
b
Thermodynamic dimer of HFP (CAS 1584-03-8) and its adduct (CAS 30320-28-6).
Table 2 — Physical properties of FK-5-1-12
Property Units Value
Molecular mass n/a 316,04
Boiling point at 1 013 bar (absolute) °C 49,2
Freezing point °C –108,0
Critical temperature °C 168,66
Critical pressure bar 18,646
Critical volume cc/mole 494,5
Critical density kg/m 639,1
Vapour pressure 20 °C bar abs 0,326 0
Liquid density 20 °C g/ml 1,616
Saturated vapour density 20 °C kg/m 4,330 5
Specific volume of superheated va-
m /kg 0,071 9
pour at 1 013 bar and 20 °C
Heat of vapourization at boiling point KJ/kg 88,0
Chemical formula
CF CF C(O)CF(CF )
3 2 3 2
Dodecafluoro-2-methylpentan-3-one
Chemical name
5 2
NOTE 1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .
4.2 Use of FK-5-1-12 systems
FK-5-1-12 total flooding systems may be used for extinguishing fires of all classes within the limits specified
in ISO 14520-1:2023, 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 14520-1:2023, 7.7.
The extinguishing concentrations and design concentrations for heptane and Surface Class A hazards are
shown in Table 4. Concentrations for other fuels are shown in Table 5 and inerting concentrations in Table 6.

Table 3 — FK-5-1-12 total flooding quantity
Temperature Specific
FK-5-1-12 mass requirements per unit volume of protected space, m/V (kg/m )
volume
T S Design concentration (by volume)
°C m /kg 3 % 4 % 5 % 6 % 7 % 8 % 9 % 10 %
–20 0,060 9 0,507 7 0,684 0 0,864 0 1,040 7 1,235 7 1,427 5 1,623 6 1,824 1
–15 0,062 3 0,496 5 0,669 0 0,845 0 1,024 8 1,208 4 1,396 1 1,587 9 1,783 9
–10 0,063 7 0,485 9 0,654 5 0,826 8 1,002 7 1,182 4 1,366 0 1,553 7 1,745 5
–5 0,065 0 0,475 6 0,640 7 0,809 4 0,981 6 1,157 5 1,337 2 1,520 9 1,708 7
0 0,066 4 0,465 8 0,627 5 0,792 6 0,961 3 1,133 6 1,309 6 1,489 5 1,673 4
5 0,067 8 0,456 4 0,614 8 0,776 6 0,941 8 1,110 6 1,283 1 1,459 3 1,639 5
10 0,069 1 0,447 3 0,602 6 0,761 2 0,923 2 1,088 6 1,257 6 1,430 4 1,607 0
15 0,070 5 0,438 6 0,590 9 0,746 4 0,905 2 1,067 4 1,233 2 1,402 6 1,575 7
20 0,071 9 0,430 2 0,579 6 0,732 2 0,887 9 1,047 1 1,209 6 1,375 8 1,545 7
25 0,073 3 0,422 2 0,568 8 0,718 4 0,871 3 1,027 5 1,187 0 1,350 0 1,516 7
30 0,074 6 0,414 4 0,558 3 0,705 2 0,855 3 1,008 6 1,165 2 1,325 2 1,488 8
35 0,076 0 0,406 9 0,548 2 0,692 5 0,839 9 0,990 4 1,144 2 1,301 3 1,462 0
40 0,077 4 0,399 7 0,538 5 0,680 2 0,825 0 0,972 8 1,123 9 1,278 3 1,436 1
45 0,078 7 0,392 8 0,529 1 0,668 4 0,810 6 0,955 9 1,104 3 1,256 0 1,411 1
50 0,080 1 0,386 0 0,520 1 0,657 0 0,796 7 0,939 5 1,085 4 1,234 5 1,386 9
55 0,081 5 0,379 5 0,511 3 0,645 9 0,783 3 0,923 7 1,067 1 1,213 7 1,363 6
60 0,082 9 0,373 3 0,502 9 0,635 2 0,770 4 0,908 4 1,049 5 1,193 6 1,341 0
65 0,084 2 0,367 2 0,494 7 0,624 7 0,757 8 0,893 6 1,032 4 1,174 2 1,319 1
70 0,085 6 0,361 3 0,486 8 0,614 8 0,745 7 0,879 3 1,015 8 1,155 4 1,298 0
75 0,087 0 0,355 6 0,479 1 0,60
...