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