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Paul Compton, Colt International LtdPaul Compton, Colt International Ltd
NFPA-APSEI Fire & Security 2010
Smoke control in industrial buildingsSmoke control in industrial buildings
Owned by O’Hea family and the Colt Foundation (charity)
Current Group Turnover £160 million (190 million Euro)
Main manufacturing plants in the UK & Holland
Represented in Portugal by Colt Portugal S.A. in Lisbon
Private British Company founded in 1931
“I J O’Hea. Colt Founder”
A brief introduction
Smoke ventilation in industrial buildings
Introduction
Average per year in Portugal:
55,000 fires
51 fire deaths
Typically 60% of fire deaths and
injuries caused or partially
caused by smoke inhalation
Decreto-Lei nº. 220/2008
Portaria nº. 1532/2008
Despacho nº. 2074/2009
Industrial and warehouse buildings are classified as type
XII according to the Decreto-Lei nº.220/2008.
Smoke ventilation in industrial buildings
Regulations in Portugal – Smoke ventilation
Type XII buildings with a risk category of 2o and above
require smoke ventilation if:
•Larger than 400m2 and
•Used as a warehouse
Design:
•Should follow an accepted norm
•Should limit smoke reservoirs to 1600m2 and 60m length
Smoke ventilation in industrial buildings
Regulations in Portugal – Smoke ventilation
• SPRINKLERS
• Will limit fire spread and
control growth
• Will not reduce smoke
damage
• VENTILATION
• Will prevent smoke
logging
• Assist escape
• Aid fire fighting
Sprinklers are designed to reduce damage, but offer
limited benefit to occupants. Smoke ventilation alone
will not save the building but is primarily designed to
assist escape.
Smoke ventilation in industrial buildings
Sprinklers and ventilation
• Life safety – by increasing time available for safe
evacuation
•Fire fighters – by improving conditions for search ad
rescue and fire fighting
• Property – by helping fire fighters, limiting smoke spread,
reducing smoke temperatures
Smoke ventilation in industrial buildings
What is protected?
Smoke ventilation in industrial buildings
Smoke spread
Y
db
margin
Smoke ventilation in industrial buildings
Components of a system
•European – CEN/TR 12101-5
•British – BS 7346-4 and BS 7346-5
•American – NFPA 204
•and many others
Smoke ventilation in industrial buildings
Design Norms
Smoke ventilation in industrial buildings
Example project (Distribution centre)
112 m x 139 m
15570 m2
22.6 m to ridge
20.1 m to valley
Design process
• Determine fire size and heat output.
• Identify clear layer height required.
• Divide roof space into smoke reservoirs.
• Calculate mass flow of smoke entering reservoir.
• Calculate smoke layer temperature.
• Establish effect of sprinklers on layer temperature, if
any.
• Calculate aerodynamic free area of natural ventilation
or extract rate for mechanical ventilation.
• Calculate plug-holing requirement and calculate
number of ventilators.
• Equipment selection, system design
Smoke ventilation in industrial buildings
Design process
Smoke ventilation in industrial buildings
Example project (Distribution centre)
Fire (in rack sprinklers): 12MW convective, 6m
perimeter
6 smoke
reservoirs –
smoke barriers
along red lines
down to 19.1m
(above racking)
Design process
• Determine fire size and heat output.
• Identify clear layer height required.
• Divide roof space into smoke reservoirs.
• Calculate mass flow of smoke entering reservoir.
• Calculate smoke layer temperature.
• Establish effect of sprinklers on layer temperature,
if any.
• Calculate aerodynamic free area of natural ventilation
or extract rate for mechanical ventilation.
• Calculate plug-holing requirement and calculate
number of ventilators.
• Equipment selection, system design
Smoke ventilation in industrial buildings
Design process
Smoke ventilation in industrial buildings
Components of a system
Mass flow
rate here
= mass
flow rate
here
STEADY STATE
Mass in = mass out
Heat in = heat out
Account for sprinkler
cooling by limiting smoke
layer temperature to
sprinkler bulb
temperature
Mass flow = 99 kg/s
Calculated smoke temperature = 135 oC
Ceiling sprinkler temperature = 141 oC
Design process
• Determine fire size and heat output.
• Identify clear layer height required.
• Divide roof space into smoke reservoirs.
• Calculate mass flow of smoke entering reservoir.
• Calculate smoke layer temperature.
• Establish effect of sprinklers on layer temperature, if
any.
• Calculate aerodynamic free area of natural
ventilation or extract rate for mechanical
ventilation.
• Calculate plug-holing requirement and calculate
number of ventilators.
• Equipment selection, system design
Smoke ventilation in industrial buildings
Design process
Smoke ventilation in industrial buildings
Components of a system
mass
flow rate
Area depends on mass
flow rate, smoke depth
and smoke temperature
Also upon ratio of inlet to
exhaust
Aerodynamic area = 21.9 m2
Minimum number of ventilators = 2 (4 chosen)
(for each reservoir – 1.3% roof area equivalent)
Depth
(3.5m)
Smoke ventilation in industrial buildings
Typical equipment
Smoke ventilation in industrial buildings
Product certification
• SHEVS need maintenance and testing
• Typical regime – Test weekly or monthly and inspect/maintain annually
• Yes it costs time and money – but it provides confidence and awareness
Smoke ventilation in industrial buildings
Maintenance
What conditions do you want for escape and fire
fighting?
A properly designed smoke ventilation system can save
lives and property – is a cheap system a false economy?
Smoke ventilation in industrial buildings
Conclusion
The End
Thank YouEnd
Thank you
Smoke ventilation in industrial buildings
NFPA-APSEI Fire & Security 2010
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