Upload
alexis-graves
View
230
Download
8
Tags:
Embed Size (px)
Citation preview
Fire-fighting & Rescue in Buildings with Engineered Solutions
Roy WilsherDirector Community Protection
& Chief Fire Officer
Fire Engineering is the application of scientific and engineering principles, rules [Codes], and expert judgement, based on an understanding of the phenomena and effects of fire and of the reaction and behaviour of people to fire, to protect people, property and the environment from the destructive effects of fire.
Definition
Modern Buildings
• Traditional design limits designers and engineers of large innovative buildings
• Designers and engineers are actively seeking more cost effective solutions
• Are today’s buildings potentially more hazardous to Firefighters?
The Issue
Modern Buildings
• Information on buildings not being passed to Firefighters
• Focus now on community fire safety
• Advent of self assessment
• Maintenance of Knowledge
What are the issues?Facades/insulation
• Glazed panels from floor to ceiling level
What are the issues?
Ventilation – in a fire, how can you
effectively ventilate a compartment
when there are
no external
openings?
What are the issues?
Large open spaces
What are the issues?Compartment sizes
Galleria Harlequin
Westgate
Howard Centre
Marlowes Jackson Square
Firefighter Override Controls
What are the issues?
Horizontal Dry Risers and Poor Fire Service Access
What are the issues?
Increased travel distances
• Corridor length - 7.5m• Can go to 17.5m• Compensatory features
(Automatic ventilation)
What are the issues? Innovative construction products & techniques
What are the issues?
Timber framed construction
Timber framed construction
Rapid fire development
False Chimneys
Two Hertfordshire Examples
News International, Cheshunt
News International, Cheshunt
News International, Cheshunt
Hillmead School, Bishop’s Stortford
Operational ConsiderationsSummary of risk critical
information• Incomplete evacuation likely: ‘persons reported’• Excessive noise levels: FA & mech. vents• Excessive firefighter penetration distances• Min. smoke level 2.5m• Intense radiated heat (200ºc at 2.5m)• Fire size > 5MW (‘good’ car fire): beyond smoke
control design criteria: total smoke logging could lead to flashover Fire size > 216m² (½ a tennis court): beyond sprinkler (& smoke control) design criteria
• Ensure entrance doors remain open (for inlet air)• Do not shut down sprinkler system.
Operational Considerations (cont.) Summary of risk critical information
• Smoke entering/exhausting from > 1 reservoir indicates system/s failure: dangerous conditions.
• Smoke control equipment rated at 300ºc for 1 hour• West Gate, Marlowes and Jackson Square sprinkler
systems fed from town main: use of incorrect hydrants could lead to supply failure/building loss
• Harlequin, Galleria and Howard Centre sprinkler systems on tank supply: 1 hour duration at the max. design capacity of 18 heads/216m² (½ a tennis court)
• Danger of backdraft, ‘blow-torch’ effect from fire in ‘sealed’ shop units out of hours (Marlowes, Westgate, Howard Centre and Harlequin). Consider overriding mechanical smoke control system.
What can we do?
• Ensure information is shared
• On Site Expertise
• Training – practice!
• Operational planning
• Involve Firefighters
• Changes to the building when in use compromises design & Firefighters!
What else needs to be done?• An effective testing regime for building
materials to ensure buildings are safe, not only for the occupants, but also for Firefighters
• This should include testing in their ‘as built’ format in realistic conditions
• Information to local fire service (manual)
Thank You
Questions