1. Fire Safety: A Sociological Perspective Graham Spinardi Ove Arup Foundation/Royal Academy of Engineering Senior Research Fellow in Integrating Technical and Social Aspects of Fire Safety Expertise and Engineering 4 June 2013

2. How is Fire Safety Social? How individuals, families, colleagues, etc cause and respond to fires – (Lifestyle, poverty, arson) – Evacuation How society (and groupings within) prepare for fires – Regulation – (Fire services) How experts know about fire and fire safety – Induction from testing and from actual fires – Deduction from theory (eg fluid dynamics)

3. Regulation Origins in major disasters – Great Fire of London 1666 => no thatch, less wood, 2 hour party walls, no projecting roofs – Edinburgh Empire Palace Theatre Fire 1911 => 2½ minutes evacuation time Insurers and suppliers – National Fire Protection Association (NFPA) origins in 1895 meeting of insurers and sprinkler manufacturers - need for standardisation of sprinkler installation Self-regulation? – Comparison with aviation (see John Downer’s work)

4. Regulatory Barriers Prescriptive building regulations/codes – to slow fire spread, aid evacuation, facilitate rescue – Testing geared towards the regulations – Inflexible and not responsive to new materials & building techniques, limits use of difficult spaces, adds cost => Shift from rigid code compliance to Performance Based Design (PBD) – ‘Assess the effects of fire from first principles early in the design’* – Computer power to model fire and smoke fluid dynamics, structural outcomes, and evacuation behaviour (quantitative and graphic outputs) *Florian Block, 'Structural Fire Engineering of Unusual Steel Structures'

5. Performance Based Design Issues: Expertise and Professional Standards PBD is more flexible, but needs regulators to have expertise and/or to trust outside review – not just ‘code- checkers’ Difficult to do if authorities have little expertise Problematic if regulators are weak, if professionals lack standards of behaviour, and if link with socially-agreed level of safety is lost – e.g. parts of Australia versus San Francisco’s ‘local equivalencies’ to the code

6. PBD, Risk, and Judgment Acceptable levels of risk – Perceptions vary according to whether seen as voluntary, controllable, catastrophic – Most deaths in domestic homes but little regulation, whereas few deaths in high-rise building but heavily regulated – Prescriptive regulations reflect social consensus, outcome of local governance PBD can make safety a matter of judgment – ‘guidance is almost exclusively qualitative in nature … can lead to inconsistent levels of safety’* – Also need judgment on reliability of the science * Fleischmann, 2011, 'Is Prescription the Future of Performance-Based Design?'

7. Learning from Fires Complex circumstances (many variables, not controlled), not fully documented Rare for some classes of building (eg modern high rises), each example unique (different designs, materials, regulatory regimes, etc) Lack of instrumentation Evidence more or less destroyed

8. Fire Safety Knowledge and Testing Controlled, but therefore not realistic – Test design – elements tested in isolation – Underlying theoretical assumptions – ‘Similarity judgments’ about whether test is sufficiently similar to real-world situations Expensive to build and burn anything like a realistic building – 1990 Broadgate fire => Cardington tests – 2006 Dalmarnock Glasgow fire tests ‘Standard’ tests central to regulatory regimes – ‘test individual components of structures in a fake scenario with a fake fire’* * Luke Bisby, March 2011, Ove Arup Foundation interview

9. Cardington Airship Hanger

10. Fire Safety Knowledge and Testing Controlled, but therefore not realistic – Test design – elements tested in isolation – Underlying theoretical assumptions – ‘Similarity judgments’ about whether test is sufficiently similar to real-world situations Expensive to build and burn anything like a realistic building – 1990 Broadgate fire => Cardington tests – 2006 Dalmarnock Glasgow fire tests ‘Standard’ tests central to regulatory regimes – ‘test individual components of structures in a fake scenario with a fake fire’* * Luke Bisby, March 2011, Ove Arup Foundation interview

11. Standard Fire Resistance Test Method stems from early Twentieth Century e.g. ASTM (American Society for Testing and Materials) E119 Building element (eg column or floor) subject to heating according to standard fire temperature-time curve Does it maintain load-bearing, integrity and insulation for long enough?

12. Criticism of Standard Fire Test ‘The difference between the standard test temperature-time curve and temperature- time curves measured in real compartment fires is considerable.’* – Does not take account of windows, ventilation, compartment shape and size – Elements tested in isolation though in building will be joined to other elements thus spreading heat *Barbara Lane, 2000, 'Performance Based Design for FIre Resistance.'

14. Fire/Smoke Dynamics Fire Dynamics Simulator (FDS)/Smokeview visualisation software – Widely used for PBD (free, developed by US National Institute of Standards and Technology) How good is this software for smoke and fire prediction? Do users understand limitations? – A priori simulation of Dalmarnock tests showed that ‘current modelling cannot provide good predictions of HRR [heat release rate] evolution (ie fire growth) in realistic complex scenarios’* Powerful tool for demonstration – could visual nature be overly persuasive to non-experts? * Rein et al, 2009, 'Round-robin study of a priori modelling predictions of the Dalmarnock Fire Test One’

15. Performance Based Design Issues: Trade-offs Active measures (sprinkler system, smoke control) can allow passive measures to be relaxed (size and height of compartments, distance to exits, fire resistance of materials) Enables innovative design, use of difficult spaces (eg new San Francisco Exploratorium in old Pier building) But important that active measures have sufficient redundancy (eg sprinklers in domestic housing in California may not work after earthquake)

16. Fire Safety and Human Behaviour Do quantitative simulations used in PBD produce spuriously accurate results? – Simulation models provide quantitative (and visual) results that may gloss over limited basic understanding (are ‘first principles’ enough?) – Human behaviour is simplified or ignored

17. Maintaining Fire Safety Who is responsible for assuring that fire safety features are maintained during a building’s life? – In many jurisdictions, regular inspections, including operational demonstrations of equipment – In UK, shift now to ‘responsible person’ and reliance on fire safety audits Critical issue when buildings are modified (eg six deaths in Lakanal House tower block, Camberwell, July 2009) PBD-based buildings may incorporate active features that need to be maintained