Fixed firefighting systems - Oxygen reduction systems - Design, installation, planning and maintenance

This European standard specifies oxygen reduction systems that are used as fire prevention systems by creating an atmosphere in an area which is having a lower permanent oxygen concentration as in ambient conditions. The level of oxygen reduction is defined by the individual risks of these areas (see Annex A). Oxygen reduction is achieved by technical systems which are providing a flux of air containing a reduced concentration of oxygen.
This European standard specifies minimum requirements and defines the specifications governing the design, installation and maintenance of fixed oxygen reduction systems with oxygen reduced air in buildings and industrial production plants. The standard also applies to the extension and modification of existing systems.
This European standard applies to oxygen reduction systems using nitrogen which are designed for continual oxygen reduction in enclosed spaces.
NOTE   Nitrogen is today the most suitable gas to be used for oxygen reduction. For other gases this European standard can be used as basis.
This European standard does not apply to oxygen reduction systems that use water mist or combustion gases.
The European standard does not apply to:
-   explosion suppression systems;
-   explosion prevention systems;
-   fire extinguishing systems using gaseous extinguishing agents;
-   inertization of portable containers;
-   systems in which oxygen levels are reduced for reasons other than fire prevention (e.g. steel processing in the presence of inert gas to avoid the formation of oxide film);
-   inerting required during repair work on systems or equipment (e.g. welding) in order to eliminate the risk of fire or explosion.
In addition to the conditions for the actual oxygen reduction system and its individual components this European standard also covers certain structural specifications for the protected area.
The space protected by an oxygen reduction system is a controlled and continuously monitored indoor climate for extended occupation. This standard does not cover unventilated confined spaces that may contain hazardous gases.

Ortsfeste Löschanlagen - Sauerstoffreduktionsanlagen - Auslegung, Einbau, Planung und Instandhaltung

Diese Europäische Norm legt Anforderungen an die Sauerstoffreduktionsanlagen fest, die als Brandvermeidungsanlagen verwendet werden, indem in einem Bereich eine Atmosphäre erzeugt wird, die eine niedrigere ständige Sauerstoffkonzentration aufweist als unter Umgebungsbedingungen. Der Grad der Sauerstoffreduktion ist durch die einzelnen Brandrisiken, die in diesen Bereichen vorherrschen, festgelegt (siehe Anhang A). Die Sauerstoffreduktion wird durch technische Systeme erreicht, die einen Volumenstrom sauerstoffreduzierter Luft erzeugen.
Diese Europäische Norm legt die Mindestanforderungen an die Auslegung, den Einbau und die Instandhaltung von ortsfesten Sauerstoffreduktionsanlagen mit sauerstoffreduzierter Luft in Gebäuden und Industrieanlagen fest und enthält die diesbezüglichen Festlegungen. Die Norm gilt auch für die Erweiterung und Änderung bereits vorhandener Anlagen.
Diese Europäische Norm gilt für Sauerstoffreduktionsanlagen mit Stickstoff zur kontinuierlichen Sauerstoffreduktion in umschlossenen Räumen.
ANMERKUNG   Stickstoff ist gegenwärtig das geeignetste Gas für die Sauerstoffreduktion. Bezüglich weiterer Gase kann diese Europäische Norm als Grundlage dienen.
Diese Europäische Norm gilt nicht für Sauerstoffreduktionsanlagen, die Wassernebel oder Verbrennungsgase verwenden.
Diese Europäische Norm gilt nicht für:
   Explosionsunterdrückungsanlagen;
   Explosionsschutzanlagen;
   Feuerlöschanlagen mit gasförmigen Feuerlöschmitteln;
   die Inertisierung tragbarer Behälter;
   Anlagen, bei denen der Sauerstoffgehalt aus anderen Gründen als der Brandvermeidung reduziert wird (z. B. Stahlverarbeitung unter Inertgas zur Vermeidung der Bildung einer Oxidschicht);
   die Inertisierung, die bei Reparaturarbeiten von Anlagen oder  Apparaturen (z. B. Schweißen) zur Vermeidung der Brand- oder Explosionsgefahr erforderlich ist.
Neben den Vorgaben für die eigentliche Sauerstoffreduktionsanlage und ihre einzelnen Bauteile behandelt die vorliegende Europäische Norm auch bestimmte bauliche Anforderungen an den Schutzbereich.
Der von einer Sauerstoffreduktionsanlage geschützte Bereich ist ein geregeltes und ständig überwachtes Innenraumklima für längere Nutzung. Diese Norm behandelt keine unbelüfteten engen Räume, in denen sich gefährliche Gase befinden können.

Installations fixes de lutte contre l'incendie - Systèmes d'appauvrissement en oxygène - Conception, installation, planification et maintenance

La présente Norme européenne spécifie les systèmes d’appauvrissement en oxygène qui sont utilisés comme systèmes de prévention incendie en créant, dans les zones protégées, une atmosphère dans laquelle la concentration en oxygène est réduite en permanence par rapport aux conditions ambiantes. Le niveau d’appauvrissement en oxygène est défini par les risques individuels identifiés dans les zones protégées (voir l’Annexe A). L’appauvrissement en oxygène est obtenu au moyen de systèmes qui fournissent un flux d’air ayant une concentration réduite en oxygène.
La présente Norme européenne spécifie les exigences minimales et définit les spécifications régissant la conception, l’installation et la maintenance des systèmes fixes d’appauvrissement en oxygène dans des bâtiments et dans des usines de production industrielle fonctionnant sous air appauvri en oxygène. La norme s’applique également à l’extension et à la modification des systèmes existants.
La présente Norme européenne s’applique aux systèmes d’appauvrissement en oxygène utilisant de l’azote, qui sont conçus pour assurer un appauvrissement continu en oxygène dans des espaces clos.
NOTE   L’azote est à l’heure actuelle le gaz le mieux adapté pour réaliser un appauvrissement en oxygène. Pour les autres gaz, la présente Norme européenne peut être utilisée comme base.
La présente Norme européenne ne s’applique pas aux systèmes d’appauvrissement en oxygène comme le brouillard d’eau ou les systèmes d’extinction gaz.
La présente Norme européenne ne s’applique pas :
-   aux systèmes anti-explosion ;
-   aux systèmes de prévention des explosions ;
-   aux systèmes d’extinction d’incendie utilisant des agents extincteurs gazeux ;
-   à l’inertage des réservoirs portatifs ;
-   aux systèmes dans lesquels les niveaux d’oxygène sont réduits pour des raisons autres que la prévention incendie (par exemple, transformation de l’acier en présence de gaz inerte pour éviter la formation d’un film d’oxyde) ;
-   à l’inertage nécessaire pendant les travaux de réparation des systèmes ou de l’équipement (par exemple, soudage) afin d’éliminer le risque d’incendie ou d’explosion.
En plus des conditions qui s’appliquent au système d’appauvrissement en oxygène proprement dit et à ses composants individuels, la présente Norme européenne couvre également certaines spécifications structurelles relatives à la zone protégée.
Un espace protégé par un système d’appauvrissement en oxygène est une zone à l’intérieur d’un bâtiment dont l’environnement est contrôlé en continu pour permettre une occupation prolongée. A contrario, la présente norme ne concerne pas les espaces confinés non ventilés susceptibles de contenir des gaz dangereux.

Vgrajeni gasilni sistemi - Sistemi z zmanjšano koncentracijo kisika - Projektiranje, vgradnja, načrtovanje in vzdrževanje

General Information

Status
Published
Publication Date
04-Oct-2020
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
03-Sep-2020
Due Date
08-Nov-2020
Completion Date
05-Oct-2020

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SLOVENSKI STANDARD
SIST EN 16750:2017+A1:2020
01-november-2020
Nadomešča:
SIST EN 16750:2017

Vgrajeni gasilni sistemi - Sistemi z zmanjšano koncentracijo kisika - Projektiranje,

vgradnja, načrtovanje in vzdrževanje

Fixed firefighting systems - Oxygen reduction systems - Design, installation, planning

and maintenance

Ortsfeste Löschanlagen - Sauerstoffreduktionsanlagen - Auslegung, Einbau, Planung

und Instandhaltung

Installations fixes de lutte contre l'incendie - Systèmes d'appauvrissement en oxygène -

Conception, installation, planification et maintenance
Ta slovenski standard je istoveten z: EN 16750:2017+A1:2020
ICS:
13.220.10 Gašenje požara Fire-fighting
SIST EN 16750:2017+A1:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 16750:2017+A1:2020
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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1
EUROPEAN STANDARD
NORME EUROPÉENNE
August 2020
EUROPÄISCHE NORM
ICS 13.220.20 Supersedes EN 16750:2017
English Version
Fixed firefighting systems - Oxygen reduction systems -
Design, installation, planning and maintenance

Installations fixes de lutte contre l'incendie - Systèmes Ortsfeste Löschanlagen - Sauerstoffreduktionsanlagen -

d'appauvrissement en oxygène - Conception, Auslegung, Einbau, Planung und Instandhaltung

installation, planification et maintenance

This European Standard was approved by CEN on 9 July 2017 and includes Amendment 1 approved by CEN on 12 July 2020.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by

translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 16750:2017+A1:2020 E

worldwide for CEN national Members.
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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 4

Introduction .................................................................................................................................................................... 5

1 Scope .................................................................................................................................................................... 6

2 Normative references .................................................................................................................................... 7

3 Terms and definitions ................................................................................................................................... 7

4 System requirements ..................................................................................................................................... 9

4.1 General ................................................................................................................................................................ 9

4.2 Personnel safety .............................................................................................................................................. 9

4.3 Effectiveness and application .................................................................................................................. 10

4.4 Alarm organization and emergency plan ............................................................................................ 10

5 Design ............................................................................................................................................................... 10

5.1 Qualification of the designer .................................................................................................................... 10

5.2 Fire protection concept .............................................................................................................................. 10

5.3 Structural specifications for the protected area ............................................................................... 11

5.4 Oxygen concentration ................................................................................................................................. 11

5.5 Oxygen reduction to prevent fire ........................................................................................................... 12

5.6 Safety margins ............................................................................................................................................... 12

5.7 Oxygen reduced air quantity .................................................................................................................... 16

5.7.1 Continuous oxygen reduction .................................................................................................................. 16

5.7.2 Emergency plan ............................................................................................................................................ 16

5.7.3 Oxygen reduced air ...................................................................................................................................... 16

5.7.4 Gaseous supply .............................................................................................................................................. 17

5.7.5 Fault signals ................................................................................................................................................... 17

5.8 Technical areas ............................................................................................................................................. 18

5.8.1 Technical area for control panel ............................................................................................................ 18

5.8.2 Technical area for reduced oxygen air generation .......................................................................... 18

6 Distribution pipework ............................................................................................................................... 19

6.1 Pipework ......................................................................................................................................................... 19

6.2 Pipe supports ................................................................................................................................................. 19

6.3 Components in the pipework ................................................................................................................... 19

7 Monitoring the oxygen concentration .................................................................................................. 20

8 Alarms and notifications ........................................................................................................................... 21

9 Control equipment ....................................................................................................................................... 22

9.1 Function ........................................................................................................................................................... 22

9.2 Requirements ................................................................................................................................................ 22

9.3 Electrical power supply ............................................................................................................................. 22

9.4 Electrical installations ................................................................................................................................ 22

9.5 Data recording ............................................................................................................................................... 22

10 System operation ......................................................................................................................................... 23

10.1 Instruction and training of personnel .................................................................................................. 23

10.2 Inspections ..................................................................................................................................................... 23

10.3 Operations log ............................................................................................................................................... 23

10.4 Further obligations ...................................................................................................................................... 23

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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)

11 Maintenance ................................................................................................................................................... 24

12 Documentation .............................................................................................................................................. 24

13 Installation ...................................................................................................................................................... 25

13.1 Qualification of the installer ..................................................................................................................... 25

13.2 General specifications, installation ........................................................................................................ 25

Annex A (normative) Ignition thresholds for oxygen reduction using nitrogen in fire

prevention ....................................................................................................................................................... 26

A.1 Ignition thresholds ....................................................................................................................................... 26

A.2 Tests to ascertain ignition thresholds of unfamiliar materials ................................................... 27

A.2.1 Cup burner tests ............................................................................................................................................ 27

A.2.2 Ignition threshold tests .............................................................................................................................. 28

A.2.2.1 General ............................................................................................................................................................. 28

A.2.2.2 Test criteria .................................................................................................................................................... 29

A.2.2.3 Test documentation ..................................................................................................................................... 29

Annex B (informative) Information for health and safety – Working in oxygen-reduction

atmospheres for reasons of fire prevention ....................................................................................... 31

B.1 General ............................................................................................................................................................. 31

B.2 Principles of occupational health ........................................................................................................... 31

B.3 Risk classes ..................................................................................................................................................... 31

B.4 Basic requirements, planning and installation .................................................................................. 32

B.5 Protective measures for all areas with oxygen-reduced atmospheres ..................................... 33

B.5.1 Structural and technical measures......................................................................................................... 33

B.5.2 Organizational measures ........................................................................................................................... 34

B.6 Risk classes and safety measures ........................................................................................................... 35

Annex C (informative) Existing national regulations for access and working in areas with

lower oxygen concentration ..................................................................................................................... 36

Bibliography ................................................................................................................................................................. 37

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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
European foreword

This document (EN 16750:2017+A1:2020) has been prepared by Technical Committee CEN/TC 191

“Fixed firefighting systems”, the secretariat of which is held by BSI.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by February 2021, and conflicting national standards

shall be withdrawn at the latest by February 2021.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes !EN 16750:2017".
This document includes Amendment 1 approved by CEN on 12 July 2020.

The start and finish of text introduced or altered by amendment is indicated in the text by tags !".

According to the CEN-CENELEC Internal Regulations, the national standards organisations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the

United Kingdom.
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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
Introduction

Oxygen reduction systems are designed to prevent fires from starting or spreading, by means of the

introduction of oxygen reduced air. Oxygen reduction systems are not designed to extinguish fires. The

design and installation shall be based on detailed knowledge of the protected area, its occupancy and

the materials in question. It is important to suit the fire protection measures to the hazard as a whole.

It is important to emphasize that across the European Union there are several regulatory and legislative

limitations for access and working in areas with lower oxygen concentration, so it is important to take

these limitations into account. Use of this European Standard can vary based on the national legislation

in each country of the European Union.
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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
1 Scope

This European standard specifies oxygen reduction systems that are used as fire prevention systems by

creating an atmosphere in an area which is having a lower permanent oxygen concentration as in

ambient conditions. The level of oxygen reduction is defined by the individual risks of these areas (see

Annex A). Oxygen reduction is achieved by technical systems which are providing a flux of air

containing a reduced concentration of oxygen.

This European standard specifies minimum requirements and defines the specifications governing the

design, installation and maintenance of fixed oxygen reduction systems with oxygen reduced air in

buildings and industrial production plants. The standard also applies to the extension and modification

of existing systems.

This European standard applies to oxygen reduction systems using nitrogen which are designed for

continual oxygen reduction in enclosed spaces.

NOTE Nitrogen is today the most suitable gas to be used for oxygen reduction. For other gases this European

standard can be used as basis.

This European standard does not apply to oxygen reduction systems that use water mist or combustion

gases.
The European standard does not apply to:
— explosion suppression systems;
— explosion prevention systems;
— fire extinguishing systems using gaseous extinguishing agents;
— inertization of portable containers;

— systems in which oxygen levels are reduced for reasons other than fire prevention (e.g. steel

processing in the presence of inert gas to avoid the formation of oxide film);

— inerting required during repair work on systems or equipment (e.g. welding) in order to eliminate

the risk of fire or explosion.

In addition to the conditions for the actual oxygen reduction system and its individual components this

European standard also covers certain structural specifications for the protected area.

The space protected by an oxygen reduction system is a controlled and continuously monitored indoor

climate for extended occupation. This standard does not cover unventilated confined spaces that may

contain hazardous gases.
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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
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.

EN 54 (all parts), Fire detection and fire alarm systems

EN 12094-1, Fixed firefighting systems — Components for gas extinguishing systems — Part 1:

Requirements and test methods for electrical automatic control and delay devices

EN 50104, Electrical apparatus for the detection and measurement of oxygen — Performance

requirements and test methods
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
Alarms
3.1.1
external alarm

alarm to emergency services such as fire brigade or permanently attended location

3.1.2
local alarm

acoustic and possibly additional visual alarm in protected areas or their immediate surroundings

3.1.3
internal alarm

acoustic and visual displays at the detection panel, possibly with additional displays at other signalling

equipment
3.1.4
alarm threshold

value of a process parameter which, when reached, triggers an alarm and, where necessary, initiates

automatic protection measures
3.1.5
alarm signal

signal to warn people at risk and/or to summon help from the emergency services and/or to provide

information about automatic response measures
3.2
design concentration
ingnition threshold including a safety margin
Note 1 to entry: See also Figure 1.

Note 2 to entry: The design concentration represents the maximum oxygen concentration which cannot be

exceeded in any time.
3.3
emergency situation
deviation from normal operation

EXAMPLE For example a significant deviation from the threshold value (scale of risk).

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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
3.4
operating pressure
pressure of a system under normal operating conditions
3.5
combustible material
A material capable of combustion or being ignited

Note 1 to entry: For the purposes of this standard, whether the quantity of a combustible material is to be

regarded as significant or not can be determined by means of a risk analysis as part of the fire protection design.

3.6
ignition threshold

maximum oxygen concentration in a mixture of a combustible material with air and inert gas, in which

there can be no ignition, determined under established test conditions

Note 1 to entry: This is a specific characteristic of combustible material and inert gas (see A.1).

3.7
detection and alarm installation

remote detection system for the reliable detection of risk to people and property

Note 1 to entry: It creates alarm reports from automatic or manually input information, issues these and detects

any faults. The transmission channels for information and alarms are monitored. Special measures are in place to

prevent any malfunction as far as possible, which may be powered electrically or otherwise. Detection and alarm

systems cover facilities for the input, transmission (through wires or wirelessly), processing and issuing of alarms,

including the necessary power supply. This standard applies to detection and alarm systems which detect and

report the scale of the risk at an early stage.
3.8
measuring zones

virtual separation of the protected volume for oxygen measuring

3.9
normal operation

situation in which the equipment, protection systems and components are able to carry out their

designated functions within their design parameters
3.10
oxygen reduced air
ambient air with an oxygen concentration lower than natural air
3.11
oxygen reduced air supply

nitrogen enriched air stream with an oxygen concentration of less than natural air ready to be

introduced into a protected volume
3.12
oxygen reduction

reduction of oxygen which increases the nitrogen concentration to prevent the ignition or spread of fire

3.13
protected volume
effective volume of the space to be protected
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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
3.14
system

combination of components whose function and compatibility guarantees the safety of the installation

3.15
technical areas

areas where either or the control panel, nitrogen production unit and other relevant system

components are placed
3.16
control panel

electrical device for monitoring, controlling and alarm of the oxygen reduction system

4 System requirements
4.1 General
An oxygen reduction system shall consist basically of:
a) a supply of oxygen reduced air;
b) a fixed pipework system with fittings, valves, nozzles, outlets;
c) oxygen sensors and control panel;
d) alarms.

Oxygen reduced air is produced by air separation or by injecting inert gas or gas mixture into the

protected area.

The oxygen concentration in the protected area shall be monitored by means of measuring equipment.

During operation, the supply of nitrogen shall be controlled automatically according to demand. Where

necessary as a result of a risk analysis additional means shall be provided to operate the supply

manually or an additional supply operated manually or automatically.

The oxygen reduction system can be equipped with automatic equipment designed to shut down

machinery and to close fire doors and other equipment, with the aim of creating and maintaining the

required oxygen concentration.
4.2 Personnel safety
Oxygen reduced air can be dangerous for personnel.

Adherence to this European Standard does not remove the user's statutory responsibility to comply

with the relevant national bodies and laws. In case no national laws exist, further information can be

found in Annex B.

Code requirements for unventilated confined spaces do not apply to space protected by oxygen

reduction system that control and continuously monitor indoor climate for extended occupation.

Personnel safety measures shall be made for the fact that neighbouring volumes can have a reduced

oxygen concentration. These areas may also need to be monitored and/or personnel safety measures

may need to be taken.

Technical or organizational measures shall be taken to prevent unauthorized people from entering

protected areas with permanently reduced oxygen levels.

The measurement system shall be designed in such a way that a loss of function or a measurement

error can in no event lead to the minimum oxygen threshold not being detected.

The spreading of the oxygen-reduced atmosphere to other areas not intended for this (e.g. through wall

openings, cable ducts, floor drainages, leaking doors, conveyor belts, etc.) shall be prevented.

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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)
4.3 Effectiveness and application

A fire risk assessment detailing the key fire protection factors shall be done. The important aspects are:

— the type and quantity of material/materials requiring protection;
— the area(s) requiring protection;

— the right dimension of the oxygen reduced air supply to maintain the reduced oxygen concentration

on its design value;
— a back-up oxygen reduced air supply, if provided;
— alarm equipment.

Oxygen reduction systems provide preventive fire protection. The introduction of nitrogen reduces the

oxygen concentration of the air, thereby preventing the ignition or spread of fire except for the

following:
— chemicals containing their own supply of oxygen, such as cellulose nitrate;

— mixtures containing oxidizing materials, such as sodium chlorate or sodium nitrate;

— chemicals cable of undergoing auto-thermal decomposition, such as some organic peroxides;

— reactive metals (such as sodium, potassium, magnesium, titanium and zirconium), reactive

hydrides or metal amides, some of which may react violently.
4.4 Alarm organization and emergency plan
An alarm organization is required for the following purposes:
— to alert affected and responsible persons;
— to alert the permanently attended location;
— to initiate other necessary protective measures.
The responsibilities for the alarm organization shall be defined.

The emergency plan should cover keywords to designate the basic measures that need to be taken in

case of emergency, too low oxygen level or fire signal.
5 Design
5.1 Qualification of the designer

The designer shall be sufficiently technically qualified to ensure effective protection.

5.2 Fire protection concept
The system design shall be part of the fire safety concept of the building.

As part of the system design a fire risk assessment might lead to further fire protection measures.

EXAMPLE Since the oxygen reduction system cannot prevent or detect smouldering or pyrolizing processes

(e.g. overheated cables) suitable smoke detection systems for the protected volume e.g. high sensitive smoke

detection systems according to EN 54–20 class A, are recommended and should be part of the main fire alarm

system of the facility.
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SIST EN 16750:2017+A1:2020
EN 16750:2017+A1:2020 (E)

Where special circumstances deviate from what is covered in this standard, for example spatial

configuration, structure, installations, combustible materials, altitude different from sea level,

temperature different from normal, fumes or gases, require special measures, the designer shall take

these into account. In these cases the appropriate authorities shall be consulted.

5.3 Structural specifications for the protected area

Structural partitions shall comply with the criteria governing the protection target, as shown in Table 1.

Building regulation specifications are unaffected by these measures.
Table 1 — Structural partitions
Level Protection target Protected Specification Achieved by
volume
Enclosing elements (walls,
floor and roof) shall be
The contents of a room
1 shall be protected Room —
sufficiently air tight over the
from internal fires.
life time to protect from
internal fires.
Enclosing elements (walls,
The contents of a room The construction
floor and roof) shall be
shall be protected of fire
sufficiently air tight over the
from internal fires and compartments
2 Room
life time and provide
from fires spreading according to the
protection against the spread
from an external relevant
of fire from the surrounding
source. guidelines.
area.

Openings shall be constantly sealed or sealable; otherwise the openings shall be reflected in the

calculation of the nitrogen production.

The user should be aware of the relationship between leakage, reduced oxygen air supply and the

system duty cycle.

In the case of oxygen reduction systems all operational openings that are not included in the calculation

of the required levels of oxygen shall be provided with closing m
...

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