SIST-TP CEN/TR 12101-5:2005

Smoke and heat control systems - Part 5: Guidelines on functional recommendations and calculation methods for smoke and heat exhaust ventilation systems

This Technical Report gives recommendations and guidance on functional and calculation methods for smoke and heat exhaust ventilation systems for steady-state design fires. It is intended for a variety of building types and applications, including single-storey buildings, mezzanine floors, warehouses with palletized or racked storage, shopping malls, atria and complex buildings, car parks, places of entertainment and public assembly and un-compartmented space within multi-storey buildings.
This Technical Report does not include any functional recommendations for design parameters where the primary purpose of the SHEVS is to assist fire-fighting.
NOTE   Such functional recommendations need to be agreed with the fire service responsible for the building in question. The calculation procedures set out in the annexes of this Technical Report can be used to design the SHEVS to meet whatever recommendations have been agreed.
This Technical Report does not cover the following:
-   smoke clearance, where smoke is exhausted from a building after the fire has been suppressed;
-   cross-ventilation, where wind-induced or fan-induced air currents sweep smoke through and out of the building, usually as part of fire-fighting operational procedures;
-   ventilation of stairwells, which usually represents a special application of smoke clearance and which does not necessarily protect the continued use of the stairwell;
-   fully-involved fires.

Rauch- und Wärmefreihaltung - Teil 5: Anleitung zu funktionellen Empfehlungen und Rechenverfahren für Anlagen zur Rauch- und Wärmefreihaltung

Systemes de contrôle de fumées et de chaleur - Partie 5 : Guide de recommandations fonctionnelles et de calcul pour les systemes d'evacuation de fumée et de chaleur

Le présent Rapport technique donne des recommandations et des indications sur les méthodes fonctionnelles et le calcul pour les systemes d’évacuation des fumées et de chaleur pour des incendies stabilisés de référence. Il est destiné a un grand nombre de types de bâtiments et d'applications, notamment des bâtiments a un niveau, des mezzanines, des entrepôts avec des systemes de stockage par palettes ou gerbé, des centres commerciaux, des atriums et des bâtiments complexes, des parcs de stationnement, des lieux de divertissement et de rassemblement du public et des espaces non compartimentés a l'intérieur de bâtiments a plusieurs niveaux.
Le présent Rapport Technique ne comporte pas de recommandations fonctionnelles pour les parametres principaux de conception lorsque l'objectif premier d'un SEFC est d'aider a la lutte contre l'incendie.
NOTE   Ces recommandations fonctionnelles doivent etre convenues par le responsable du service incendie pour le bâtiment concerné. Toutefois, les modes opératoires de calcul établis dans les annexes du présent Rapport Technique peuvent servir a concevoir un SEFC qui réponde aux recommandations convenues.
Le présent Rapport Technique ne couvre pas ce qui suit :
-   l'évacuation de fumée, lorsque la fumée s'échappe d'un bâtiment apres extinction de l'incendie ;
-   la ventilation transversale, lorsque des courants d'air dus au vent ou a des ventilateurs balaient la fumée dans le bâtiment et en dehors, généralement dans le cadre de modes opératoires de lutte contre l'incendie ;
-   la ventilation de cages d'escalier, qui constitue généralement une application particuliere d'évacuation de fumée et ne protege pas nécessairement l'utilisation continue de la cage d'escalier ;
-   les feux auto-entretenus.

Sistemi za nadzor dima in toplote – 5. del: Navodila za delovanje in računske metode za sisteme za odvod dima in toplote

General Information

• Status: Published
• Publication Date: 30-Nov-2005
• ICS: 13.220.20 - Fire protection
• ICS: 91.140.30 - Ventilation and air-conditioning systems
• Technical Committee: POZ - Požarna varnost
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2005
• Due Date: 01-Dec-2005
• Completion Date: 01-Dec-2005
• Ref Project: CEN/TR 12101-5:2005 - Smoke and heat control systems - Part 5: Guidelines on functional recommendations and calculation methods for smoke and heat exhaust ventilation systems

Relations

• Replaces: SIST CR 12101-5:2001 - Smoke and heat control systems - Part 5: Guidelines on functional recommendations and calculation methods for smoke and heat exhaust ventilation systems
• Effective Date: 01-Dec-2005

Standards Content (Sample)

SLOVENSKI STANDARD
SIST-TP CEN/TR 12101-5:2005
01-december-2005
1DGRPHãþD
SIST CR 12101-5:2001
6LVWHPL]DQDG]RUGLPDLQWRSORWH±GHO1DYRGLOD]DGHORYDQMHLQUDþXQVNH
PHWRGH]DVLVWHPH]DRGYRGGLPDLQWRSORWH
Smoke and heat control systems - Part 5: Guidelines on functional recommendations
and calculation methods for smoke and heat exhaust ventilation systems
Rauch- und Wärmefreihaltung - Teil 5: Anleitung zu funktionellen Empfehlungen und
Rechenverfahren für Anlagen zur Rauch- und Wärmefreihaltung
Systemes de contrôle de fumées et de chaleur - Partie 5 : Guide de recommandations
fonctionnelles et de calcul pour les systemes d'evacuation de fumée et de chaleur
Ta slovenski standard je istoveten z: CEN/TR 12101-5:2005
ICS:
13.220.20 3RåDUQD]DãþLWD Fire protection
91.140.30 3UH]UDþHYDOQLLQNOLPDWVNL Ventilation and air-
VLVWHPL conditioning
SIST-TP CEN/TR 12101-5:2005 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TP CEN/TR 12101-5:2005

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SIST-TP CEN/TR 12101-5:2005
TECHNICAL REPORT
CEN/TR 12101-5
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
October 2005
ICS 13.220.99; 23.120 Supersedes CR 12101-5:2000
English Version
Smoke and heat control systems - Part 5: Guidelines on
functional recommendations and calculation methods for smoke
and heat exhaust ventilation systems
Systèmes de contrôle de fumées et de chaleur - Partie 5 : Rauch- und Wärmefreihaltung - Teil 5: Anleitung zu
Guide de recommandations fonctionnelles et de calcul pour funktionellen Empfehlungen und Rechenverfahren für
les systèmes d'exutoires de fumées et de chaleur Anlagen zur Rauch- und Wärmefreihaltung
This Technical Report was approved by CEN on 30 September 2005. It has been drawn up by the Technical Committee CEN/TC 191.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 12101-5:2005: E
worldwide for CEN national Members.

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Contents Page
Foreword. 4
Introduction . 5
1 Scope. 9
2 Normative references. 9
3 Terms, definitions, symbols and units. 9
3.1 Terms and definitions . 9
3.2 Symbols and units. 15
4 General recommendations . 21
4.1 Design objectives . 21
4.2 Reliability . 21
4.3 Combined use of natural and powered ventilators. 22
4.4 Sequence of operation of devices comprising a single SHEVS . 23
4.5 Interactions between different smoke zones in a building. 23
4.6 Sprinkler protection. 24
4.7 Documentation . 24
4.8 Installation, maintenance and safety . 26
5 Calculation procedures. 26

5.1 General . 26
5.2 Design regions. 27
5.3 Additional steps in the calculation. 28
5.4 Compatibility. 30
6 Performance recommendations. 30
6.1 The fire as a basis for design . 30
6.2 Plumes rising directly from the fire into a smoke reservoir. 33
6.3 The flow of hot smoky gases out of a fire-room into an adjacent space . 34
6.4 The flow of hot smoky gases under a canopy projecting beyond a fire-room’s

window or opening. 35
6.5 The spill plume . 36
6.6 The smoke reservoir and ventilators . 40
6.7 External influences. 42
6.8 Inlet air (replacement air) . 44
6.9 Free-hanging smoke barriers . 46
6.10 Suspended ceilings. 47
6.11 Atrium depressurization . 48
7 Interaction with other fire protection systems and other building systems . 50

7.1 Sprinklers. 50
7.2 Smoke and fire detection systems. 50
7.3 Pressure differential systems. 51
7.4 Public address and voice alarm systems . 52
7.5 Lighting and signage. 52
7.6 Computerized control systems . 52
7.7 Heating, ventilation and air-conditioning (HVAC) . 53
7.8 Security systems . 54
Annex A (informative) Default value heat release rates . 55
Annex B (informative) The plume rising directly from the fire into a smoke reservoir. 56
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Annex C (informative) The flow of hot smoky gases out of a fire-room into an adjacent
space . 60
Annex D (informative) The flow of hot smoky gases under a soffit projecting beyond a
fire-room’s opening or window . 64
Annex E (informative) The spill plume. 68
Annex F (informative) The smoke reservoir and ventilators. 69
Annex G (informative) The influence of zones of overpressure and/or zones of suction
upon a SHEVS. 74
Annex H (informative) Deflection of free-hanging smoke barriers. 77
Annex I (informative) Plenum chamber . 82
Annex J (informative) Atrium depressurization. 84
Annex K (informative) The interaction of sprinklers, a SHEVS and fire-fighting actions . 91
Annex L (informative) The effect of a buoyant layer on the minimum pressure
recommended for a pressure differential system . 93
Bibliography . 96

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Foreword
This CEN Technical Report (CEN/TR 12101-5:2005) has been prepared by Technical Committee
CEN/TC 191 “Fixed firefighting systems”, the secretariat of which is held by BSI.
This Technical Report supersedes CR 12101-5:2000.
This Technical Report is based on the text of British Standard BS 7346-4:2003.
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Introduction
0.1 General introduction
Smoke and heat exhaust ventilation systems (SHEVS) create a smoke free layer above a floor by
removing smoke. They can, therefore, improve conditions to allow the safe escape and/or rescue of
people and animals, to protect property and to permit a fire to be fought while still in its early stages.
Ventilation systems for smoke removal also serve simultaneously for heat exhaust and can exhaust
hot gases released by a fire in the developing stage.
The use of such systems to create smoke free areas beneath a buoyant smoke layer has become
widespread. Their value in assisting in the evacuation of people from buildings, reducing fire damage
and financial loss by preventing smoke logging, facilitating fire-fighting, reducing roof temperatures
and retarding the lateral spread of fire is firmly established. For these benefits to be realised it is
crucial that smoke and heat exhaust ventilators operate fully and reliably whenever called upon to do
so during their installed life.
Components for a SHEVS need be installed as part of a properly designed smoke and heat exhaust
system. Natural SHEVS operate on the basis of the thermal buoyancy of the gases produced by a fire.
The performance of these installations depends, for example, on:
 the temperature of the smoke;
 the fire size;
 the aerodynamic free area of the ventilators, or the volume of smoke exhausted by powered
ventilators;
 the wind influence;
 the size, geometry and location of the inlet air openings;
 the size, geometry and location of smoke reservoirs;
 the time of actuation;
 the arrangements and dimensions of the building.
Ideally the design fire upon which calculations are based shows the physical size and heat output of
the fire changing with time in a realistic manner, allowing the growing threat to occupants, property
and fire-fighters to be calculated as time progresses. Such time-based calculations of the time-to-
danger usually have to be compared with separate assessments of the time recommended for safe
evacuation of occupants of the building or of the time recommended for initiation of successful fire-
fighting. These latter assessment procedures fall outside the scope of this Technical Report, although
it is anticipated to supplement this Technical Report with design procedures for time-dependant fires
in the future. In these calculations fire growth curves are selected that are appropriate to the precise
circumstances of the building occupancies, fuel arrangements and sprinkler performance, where
appropriate. Where such information is available, these calculations are conducted on a case-by-case
basis using recommended fire safety engineering procedures. Even where such an approach is
adopted, appropriate performance recommendations, e.g. minimum clear height, external influences,
can be drawn from this Technical Report.
Where such time-based calculations are not feasible, it is possible to use a simpler procedure based
on the largest size a fire is reasonably likely to reach in the circumstances. This time-independent or
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steady-state design is not to be confused with steady fires, which achieve full size instantly and then
burn steadily. Rather the procedure assumes that a SHEVS that is able to cope with the largest fire
can also cope with the (usually earlier) smaller stages of the fire.
In practice, it is much easier to assess the largest reasonably likely size of fire than to assess the
growth rate of that fire.
0.2 Smoke exhaust ventilation design philosophies
0.2.1 Protection of means of escape (life safety)
A common approach to protect a means of escape is to achieve a smoke-free height beneath a
thermally buoyant smoke layer below a ceiling. A SHEVS uses this principle to allow the continued
use of escape routes that are in the same space as the fire, e.g. within enclosed shopping malls and
many atria. The rate of smoke exhaust (using either natural smoke exhaust ventilators or powered
smoke exhaust ventilators) is calculated to keep the smoke at a safe height above the heads of
people using the escape routes, and to keep the radiated heat from the smoke layer at a low enough
value to allow the escape routes to be used freely, even while the fire is still burning.
0.2.2 Temperature control
Where the height of clear air beneath the thermally buoyant smoke layer is not a critical design
parameter, it is possible to use the calculation procedures in 0.2.1 in a different way. The rate of
smoke exhaust can be designed to achieve (for a specified size of fire) a particular value for the
temperature of the gases in the buoyant layer. This allows the use of materials that would otherwise
be damaged by the hot gases. A typical example is where an atrium façade has glazing that is not
fire-resisting, but which is known to be able to survive gas temperatures up to a specified value. The
use of a temperature control SHEVS in such a case could, for example, allow the adoption of a
phased evacuation strategy from higher storeys separated from the atrium only by such glazing.
0.2.3 Assisting the fire-fighting operation
In order for fire-fighters to deal successfully with a fire in a building, it is first necessary for them to
drive their fire appliances to entrances that give them access to the interior of the building. They then
need to transport themselves and their equipment from this point to the scene of the fire.
In extensive and multi-storey complex buildings this can be a long process and involve travel to upper
or lower levels. Even in single-storey buildings the fire-fighters within the building need, amongst other
things, an adequate supply of water at sufficient pressure to enable them to deal with the fire. The
presence of heat and smoke can seriously hamper and delay fire-fighters’ efforts to effect rescues
and carry out fire-fighting operations. The provision of SHEVS to assist means of escape or to protect
property aids fire-fighting. It is possible to design a SHEVS similar to that described in 0.2.1 to provide
fire-fighters with a clear air region below the buoyant smoke layer, to make it easier and quicker for
them to find and to fight the fire. Temperature control designs are of less benefit.
This Technical Report does not include any functional recommendations for key design parameters
where the primary purpose of the SHEVS is to assist fire-fighting. Such functional recommendations
need to be agreed by the fire service responsible for the building in question. However, the calculation
procedures set out in the annexes of this Technical Report can be used to design the SHEVS to meet
whatever recommendations have been agreed.
0.2.4 Property protection
Smoke exhaust ventilation cannot by itself prevent fires growing larger but it does guarantee that a
fire in a ventilated space has a continuing supply of oxygen to keep growing.
It follows that smoke exhaust ventilation can only protect property by allowing active intervention by
the fire services to be quicker and more effective. Property protection is therefore regarded as a
special case of 0.2.3. Depending on the materials present, a property protection design philosophy
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can be based on the need to maintain the hot buoyant smoke layer above sensitive materials (similar
in principle to 0.2.1), or the need to maintain the smoke layer below a critical temperature (similar to
0.2.2). In either case, the functional recommendations for key parameters on which the design is
based need not be the same as where the primary purpose is life safety and will depend on the
circumstances applying in each case. These key functional recommendations need to be agreed with
all relevant interested parties. The calculation procedures in the annexes of this Technical Report can
be used to design the SHEVS.
0.2.5 Depressurization
Where a smoke layer is very deep, and storeys adjacent to the layer are linked to it by small openings,
e.g. door cracks or small ventilation grilles in walls, it can be possible to prevent the passage of
smoke through the small openings by reducing the pressure of the gases in the smoke layer. This
approach is known as depressurization, and in the form described is mainly used for atrium buildings.
The primary purpose of the technique is to prevent the entry of smoke into the spaces adjacent to the
atrium, and not to provide protection to the atrium itself. The most common name given to the
technique is atrium depressurization.
The design of atrium depressurization places additional recommendations on the design of the
SHEVS installed in the atrium. These recommendations are given in 6.11.
0.3 Applications of smoke and heat exhaust ventilation
SHEVS can create and maintain a clear layer beneath the smoke to:
a) keep the escape and access routes free;
b) facilitate fire-fighting operations;
c) reduce the potential for flashover and thus full development of the fire;
d) protect equipment and furnishings;
e) reduce thermal effects on structural components during a fire;
f) reduce damage caused by thermal decomposition products and hot gases.
SHEVS are used in buildings where the particular (large) dimensions, shape or configuration make
smoke control necessary.
Typical examples are:
 single and multi-storey shopping malls;
 large retail units;
 single and multi-storey industrial buildings and sprinklered warehouses;
 atria and complex buildings;
 enclosed car parks;
 stairways;
 tunnels;
 theatres.
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The choice of either a powered or natural SHEVS depends on aspects of the building’s design and
sitting in relation to its surroundings.
Special conditions apply where gaseous extinguishing systems, e.g. systems conforming to EN 12094
or ISO 14520, are used. Usually, gaseous extinguishing systems are not compatible with a SHEVS.
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1 Scope
This Technical Report gives recommendations and guidance on functional and calculation methods
for smoke and heat exhaust ventilation systems for steady-state design fires. It is intended for a
variety of building types and applications, including single-storey buildings, mezzanine floors,
warehouses with palletized or racked storage, shopping malls, atria and complex buildings, car parks,
places of entertainment and public assembly and un-compartmented space within multi-storey
buildings.
This Technical Report does not include any functional recommendations for design parameters where
the primary purpose of the SHEVS is to assist fire-fighting.
NOTE Such functional recommendations need to be agreed with the fire service responsible for the building
in question. The calculation procedures set out in the annexes of this Technical Report can be used to design the
SHEVS to meet whatever recommendations have been agreed.
This Technical Report does not cover the following:
 smoke clearance, where smoke is exhausted from a building after the fire has been suppressed;
 cross-ventilation, where wind-induced or fan-induced air currents sweep smoke through and out
of the building, usually as part of fire-fighting operational procedures;
 ventilation of stairwells, which usually represents a special application of smoke clearance and
which does not necessarily protect the continued use of the stairwell;
 fully-involved fires.
2 Normative references
Not applicable.
3 Terms, definitions, symbols and units
3.1 Terms and definitions
For the purposes of this Technical Report, the following terms and definitions apply.
3.1.1
adhered plume
spill plume rising against a vertical surface and into which air entrains on one side, although there
may be free ends
NOTE This is sometimes referred to as a single-sided plume.
3.1.2
aerodynamic free area
product of the geometric area and the coefficient of discharge
3.1.3
ambient
property of the surroundings
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3.1.4
atrium
enclosed space, not necessarily vertically aligned, passing through two or more storeys in a building
NOTE Lift wells, escalator shafts, building services ducts and protected stairways are not classified as atria.
3.1.5
attendance time
time taken for the arrival of the fire services at a fire scene after receipt of the initial call at the fire
brigade control room
3.1.6
authority
organization, officer or individual responsible for approving SHEVS and/or sprinkler systems,
equipment and procedures
NOTE An authority might be a fire and building control authority, a fire insurer, or another appropriate public
authority.
3.1.7
automatic activation
initiation of an operation without direct human intervention
3.1.8
backdraft
sudden deflagration caused by admitting fresh air into a room or compartment containing vitiated air,
un-burnt fuel gases and a source of ignition
3.1.9
ceiling jet
flow of smoke under a ceiling, extending outwards from the point of fire plume impingement on the
ceiling
NOTE The temperature of a ceiling jet is usually greater than the adjacent smoke layer.
3.1.10
channelling screen
smoke barrier installed beneath a balcony or projecting canopy to direct the flow of smoke and hot
gases from a room opening to the spill edge
3.1.11
coefficient of discharge
ratio of actual flow rate, measured under specified conditions, to the theoretical flow rate through the
ventilator (C ) or through an inlet opening (C )
v i
NOTE 1 This is sometimes referred to as aerodynamic efficiency.
NOTE 2 EN 12101-1 defines the coefficient of discharge in terms of the theoretical flow rate through the
ventilator only. The coefficient of discharge takes into account any obstructions in the ventilator, such as controls,
louvres or vanes and the effect of external side-winds.
3.1.12
convective heat flux
total heat energy carried by the gases crossing a specified boundary per unit time
3.1.13
depressurization
control of smoke using pressure differentials whereby the air pressure in the fire zone or adjacent
accommodation is reduced to below that in the protected space
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3.1.14
design fire
hypothetical fire having characteristics that are sufficiently severe for it to serve as the basis of the
design of a smoke and heat exhaust ventilation system
3.1.15
exhaust ventilator
device used to move gases out of a building
3.1.16
fire compartment
enclosed space, comprising one or more separate spaces, bounded by elements of construction
having a specified fire resistance and intended to prevent the spread of fire (in either direction) for a
given period of time
NOTE The term is not to be confused with room of origin or fire cell.
3.1.17
fire operational position
position or configuration of a component specified by the design of the system during a fire
3.1.18
flashover
rapid transition from a fuel-bed controlled fire to a state of total surface involvement of combustible
materials in a fire within an enclosure
3.1.19
free plume
spill plume into which air can be freely entrained into both long sides of the plume
NOTE The plume can also have free ends. Free plumes are sometimes referred to as double-sided plumes.
3.1.20
free-hanging smoke barrier
smoke barrier fixed only along its top edge
3.1.21
fuel-bed controlled fire
fire in which the rate of combustion, heat output and fire growth are primarily dependent on the fuel
being burned
3.1.22
fully-involved fire
fire in which all surfaces of the combustible materials are totally involved
NOTE This is also referred to as a fully-developed fire.
3.1.23
geometric area
area of the opening through a ventilator, measured in the plane defined by the surface of the building,
where it contacts the structure of the ventilator
NOTE Geometric area is expressed as A . No reduction is made for controls, louvres or other obstructions.
v
3.1.24
heat flux
total heat energy crossing a specified boundary per unit time
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3.1.25
heat release rate
calorific energy released by a material, product or assemblage of fuels during combustion under
specified conditions per unit time
3.1.26
manual operation
initiation of the operation of a smoke and heat exhaust ventilation system by a human action
NOTE This initiation might be performed, for example, by pressing a button or pulling a handle. A sequence
of automatic actions started by an initial human action is regarded as a manual operation for the purposes of this
Technical Report.
3.1.27
mass flux
total mass of gases crossing a specified boundary per unit time
3.1.28
mezzanine floor
intermediate floor level between any two storeys, or between the floor and roof of a building having a
smaller area than the floor below
3.1.29
natural ventilation
ventilation caused by buoyancy forces resulting from differences in density between smoky and
ambient air gases due to temperature differences
3.1.30
neutral pressure plane
height within a building where the internal air pressure is equal to the air pressure outside the building
at the same height
3.1.31
powered ventilation
ventilation that is caused by the application of external energy to displace gases through a ventilator
NOTE Fans are usually used to produce powered ventilation.
3.1.32
pressure differential system
system of fans, ducts, vents and other features provided for the purpose of creating a lower pressure
in a fire zone than in a protected space
3.1.33
quick response sprinkler
½ ½
sprinkler that has a response time index of less than 50 m s and therefore responds at an early
stage of fire development
NOTE EN
...