POSITION PAPER
ON THE FIRE PROTECTION OF CAR PARKS
2008:8(1)
Published by:
bvfa - Bundesverband Technischer Brandschutz e.V.
Koellikerstr.13 - 97074 Würzburg
www.bvfa.de
Dieses Positionspapier wird unterstützt von den nationalen Mitgliedsverbänden und Mitgliedsfi rmen von
EUROFEU, deren nachfolgende Firmen Vertreter in die Sektion Sprinkler delegiert haben:
Bravida Danmark - CLF Satrem, France - GW Sprinkler A/S Germany - JOMOS EuroSprinkler AG Switzerland
- Kuijpers Brandbeveiliging Netherlands - Minimax GmbH & Co.KG, Germany - Total Walther GmbH Zentrale
Köln, Germany - Tyco Building Service Italy - Typo Fire & Integrated Solutions Belgium - Tyco Fire & Security
Solutions Danmark - Vinci Energies S.A, France - Verenigung Sprinkler Installateurs, Netherlands - Wormald
Ansul Ltd, United Kingdom
1. Scope
The purpose of this document is to provide basic information to non-specialists that need to evalu-
ate the fi re hazards and the possible fi re protection concepts for automatic and non-automatic car
parks.
It sets out both the principal benefi ts of protection with water based fi re fi ghting systems and the
known limitations or disadvantages, when compared to alternative protection methodologies. The
guidance provided is generic and may need to be modifi ed to suit a particular system or future pro-
duct developments.
2. Introduction
Car parks are buildings which in themselves present particular problems when fi res take place. The
building design creates natural horizontal and vertical fl ues, and the style of architecture increases
the dangers with the fi re hazards present in such buildings. These hazards include fl ammable liquids
and easily ignitable combustibles, having a high fi re load, including plastics, rubber, textiles, etc.
(many due to modern innovation), all of which have high heat and smoke generation potential.
Not only is the high fi re load of concern, but a more critical aspect is the danger of the fi re growing
rapidly in the early stages.
The close concentration of cars in large open areas creates a high fi re load, a very rapid rate of growth
of fi re and particular diffi culties in locating and fi ghting such a fi re.
Sources of ignition are plentiful, such as cigarette disposal, portable heaters (?), damaged electrical
cables, etc.. The vast amounts of hot, dense, black smoke created by such a fi re, plus the possibility
of “fl ashover” makes the whole scene most dangerous for drivers and passengers who may be trapped
in cars or in locations of the building. It is also diffi cult and dangerous for fi refi ghters who eventually
will attempt to control and extinguish the fi re.
Toxic smoke penetration into perceived escape routes is a highly dangerous possibility.
The cost of such fi res in human, economic and environmental terms is incalculable, and as many of
these car parks are in “down town” city locations the consequential costs could be catastrophic.
Unfortunately all these consequences seem to be ignored by investors, owners and the appropriate
authorities.
horizontal fi re spread 1
horizontal fi re spread 2
fully developed fi re
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3. Protection using sprinkler systems
Automatic sprinkler systems have been installed for well over 100 years in all types and classes of in-
dustrial, commercial and residential buildings, and have well proven outstanding success in detecting
and suppressing or extinguishing fi res and sounding an alarm, resulting in the considerable saving of
property (both buildings and contents) and lives.
Advantages of sprinkler systems
• A sprinkler system automatically locates a fi re, detects the fi re whilst relatively small and either
suppresses or extinguishes the fi re in the early stages whilst instantaneously giving an alarm.
• There has been continuous development in the design and development of sprinkler systems, and
modern installations are highly reliable and yet sensitive in response.
• Only the sprinklers in the immediate vicinity of a fi re operate, and they immediately suppress the
fi re with a drenching spray of water and simultaneously give an alarm which can transformed to
a Fire Brigade.
• The spray of water from a sprinkler is much less in rate of fl ow than needed by the fi re brigade,
and yet it is more effective because it has operated and suppressed the fi re whilst relatively small,
so reducing the heat, smoke and fl ames to minimal proportion.
• Consequently, a sprinkler system automatically protects a building, its contents and personnel in-
volved, including fi refi ghters, whilst the fi re is quite small and it considerably reduces the extent
of the fi re involvement.
• When the Fire Brigade arrives, they can immediately locate the fi re and they are now faced with
much less hazardous circumstances than otherwise would be the case.
• Sprinkler systems can allow a reduction in the fi re rating of “passive” protection, i.e. walls, etc.,
and can allow larger areas in communication in buildings to be permitted, depending on circum-
stances.
• The most modern car designs, with increased fl ammability, are adequately protected by the latest
sprinkler system designs because rapid rises in temperature cause earlier operation of the system
which prevents faster fi re spread, thus causing much less smoke and heat. Although sensitive to
rapid heat increases caused by fi re, inadvertent operation of a sprinkler system is virtually unk-
nown due to “built in” integrity.
fi re test arrangement
smoke generation
sprinkler system working
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4. Protection with special ventilation systems combined with electronic fi re detection systems
In recent years, new ventilation systems combined with electronic fi re detection are being considered
as occasionally it may be suggested that such measures eliminate the necessity for fi re walls and
sprinklers.
Such new technologies may be useful, but they should clearly be considered as an addition to, not in
place of, to the well proven automatic fi re suppression sprinkler system.
The many different designs of car parks involving automatic and non-automatic parking with dif-
fering plan layouts and heights, can raise doubts to the advisability of the sole use of ventilation
systems with fi re detection. In the table below are comparisons between automatic sprinkler systems
and ventilation systems.
Ventilation system
Sprinkler System
Detection of fi re
Yes
Yes
Locations of fi re
Yes
Yes
Automatically fi ght the fi re
No
Yes
Limit fi re size
No
Yes
Prevent fi re spread
No
Yes
Limit the amount of smoke
No
Yes
Limit fi nancial consequences to a mini-
No
Yes
mum
4.1 Detection and location of fi re
Electronic detection systems have the facility to detect, locate and give an alarm in the very early
stages of a fi re. Something then needs to be done with a now rapidly growing fi re in an highly obs-
tructed location. Fast action is critical. This is when a reliable automatic fast acting water spraying
systems (sprinklers) is a vital necessity.
In recent years, the industry has developed a much quicker operating sprinkler which has the same
integrity as previous designs (i.e. it is just as resistant to inadvertent operation). Hence, fast growing
fi res are now detected and suppressed more quickly.
Ventilation systems are not active in fi re suppression, and do not limit or control the fi re size, nor do
they prevent fi re spread. After a ventilation system with a detection system has detected the fi re, the
Fire Brigade will be summoned and they may be ready on site to fi ght the fi re in say 15 or 20 minutes
after detection. During this time, the ventilators have to blow the increasing smoke in one direction
through the car park into ventilation shafts, and large fans blow out the smoke from the car park.
In addition, on the side of the building ventilation intake shafts must be installed to bring in fresh
air to compensate the air losses. Consideration needs to be given to the effect on the fi re that these
increased air quantities and velocities will have.
In the event of a fi re, a sprinkler system starts immediately to suppress the fi re after the operation of
a sprinkler, and the giving of the alarm. Due to the cooling effect of the water, temperatures decrease
very quickly and the fi re size is reduced and controlled. Fire tests on cars in buildings with sprinklers
have shown that fi re spread between cars does not occur in sprinklered buildings. Also, as a result
of these tests, it was shown that during the time of the fi re there was no reduction in visibility by
smoke and steam.
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Consequently the Fire Brigade would have no problems in achieving fi nal extinguishment.
Hence, a sprinkler system enables the Fire Brigade to effect extinguishment much more quickly and
safely.
4.2 Financial consequences
Due to the quick response of an automatic sprinkler system causing limitation of fi re size, reduced
fi re spread and limitation of smoke, the fi nancial consequences of a fi re in a sprinklered building are
reduced to an absolute minimum.
4.3 Automated car park systems
The many different designs of car parks such as automatic and non-automatic need different tech-
nical solutions.
For automatic car parks, sprinkler systems or, in extreme circumstances, automatic water deluge
systems have proven reliability and performance.
4.4 Conclusion:
The purpose of ventilation systems is to clear the hot gases, not to suppress the fi re. Ventilation sys-
tems may serve as an addition to sprinkler systems, but only if the ventilation system is designed and
installed in such a way that it does not interfere with the sprinkler system. This is vitally important.
Ventilation systems, producing high “wind” velocities may lead to serious delay in the response of
sprinklers and disastrously interfere with the effectiveness of the sprinkler system.
5. Automatic car parks
The situation gets worse in so called automatic car parks. These facilities were especially developed for
cities with restricted space, and they allow the parking of many cars in comparatively small areas and
volumes by using a rack structure (i.e. cars are stacked vertically as well as horizontally). In order to
minimise building costs, such systems also use very small horizontal distances between car stacks. Con-
sequently, a fi re will spread to adjacent cars even quicker than in a conventional car park. Furthermore,
automatic car parks typically park cars in multiple levels. Consequently the fi re will not only spread
horizontally but also vertically, and even more rapidly.
The closely packed confi guration of automatic car parks, which very much resembles high rack storage
in warehouses, reduces the time between the initial fi re and a “fl ashover” situation. A Fire Brigade will
not only need to get to the car park very quickly, but it will also have to determine the origin of the fi re
very rapidly and effect suppression. This is extremely diffi cult and time consuming in the case of auto-
matic car parks due to the fact that the fi re has to be located in a complex three-dimensional structure
with very restricted access routes.
If such a fi re is not controlled very rapidly and whilst small, then within minutes not only the volume
of the car park but potentially the city area around the car park building will be fi lled with toxic smoke,
resulting in collateral damage even worse than that experienced with conventional car parks. Also, if
such a fi re is not detected and controlled very quickly (i.e. within minutes) temperatures will increase
exponentially resulting in damage to the steel structure as well as to the remainder of the building.
Due to the foregoing, in Germany automatic car parks with more than 20 car spaces are required to be
protected by an approved sprinkler system.
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The installation of a sprinkler system customised to the car park geometry can limit a fi re to a single car
whilst simultaneously giving an alarm. This gives the Fire Brigade the necessary time to get to the fi re
and, with hoses and branchpipes, to effect extinguishment.
In such occupancies as automatic multi-stack car parks, the addition of foam to the sprinkler system is
highly recommended as it has the ability to spread an extinguishing facility over any liquid pool fi res,
contribute to the effectiveness of extinguishment in general, and minimise re-ignition potential.
6. Building regulations
Due to the foregoing, some of the European countries require sprinkler protection in car parks, especially
for underground car parks and/or automatic car parks
7. Table of Comparisons
Fire detection system plus
Sprinkler system
(special) ventilation system
Technical criteria
Reduction of the amount of heat produced
NO
YES
by the fi re
Reduction of the amount of smoke produced NO
YES
by the fi re
Preserving of the structural integrity of the
POSSIBLY
YES
building
Ensuring of evacuation conditions
DOUBTFUL
YES
Fire detection
YES
YES
Automatic alarm transmission
YES
YES
Ensuring of safe access to the fi re for the fi re NOT PROVEN
YES
brigade
Reduction of environmental pollution
NO
YES
Economic criteria
Reduction of business interruption of car
NO
YES
park in case of fi re
Reduction of costs for other fi re protection
NO
POSSIBLY
means
Limitation of damage to cars in the car park
NO
YES
Limitation of damage to the technical equip- NO
YES
ment of the car park
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