DR J H BURGOYNE AND PARTNERS LLP FORENSIC SERVICES

Transcription

1 DR J H BURGOYNE AND PARTNERS LLP FORENSIC SERVICES

2 ROSEPARK CARE HOME Investigation of the cause of the Fire on 31 January 2004

3 POLICE CONTACTED BURGOYNES Initial contact, evening of Saturday 31 January 2004 Could we assist with fire alarm system memory? Initial site visit, 14:00 hours of 1 February 2004 Look at equipment and provide advice

4 OVERVIEW Fire in a cupboard Large number of fatalities Recent changes to the fire alarm system Need to determine cause of fire and why so many deaths occurred

5 INITIAL AIMS Ascertain if the fire alarm panel had a memory To interrogate any fire alarm system memory Time of the essence system memory loss

6 REQUIRED INFORMATION Which alarm activated first? When was the first alarm activation? When and in what order did subsequent alarm activations occur?

7 THE PANEL DID NOT HAVE A MEMORY Concerns about whether the system gave the correct alarm, leading to delays in detection Were any problems caused by the fire alarm panel change?

8 SYSTEM CHECKING Burgoynes managed the process and ensured that the information gathering met appropriate standards Chubb undertook the actual checks, under Burgoyne s guidance.

9 THE FIRE ALARM SYSTEM The panel worked correctly The surviving detectors and sounders worked correctly The fire alarm zones crossed fire boundaries

10 Smoke first seen by Mr Norton Offices Accommodation Accommodation Fire alarm panel Dining area, kitchens and lounge Zone 1 Entrance foyer Corridor Lift Corridor Zone 2 Accommodation Games cupboard Area of direct fire attack Fire Accommodation Area of direct fire attack Corridor Zone 3 Accommodation Stairwell

11 Smoke first seen by Mr Norton Offices Accommodation Accommodation Fire alarm panel Dining area, kitchens and lounge Zone 1 Entrance foyer Corridor Lift Corridor Zone 2 Accommodation Games cupboard Area of direct fire attack Fire Accommodation Area of direct fire attack Corridor Zone 3 Accommodation Stairwell

12 MAIN CONCERNS WITH THE FIRE ALARM SYSTEM Zoning crossed fire barriers Poor zone descriptions No mimic diagram as BS 5839: Part 1, 1988 Zones not tested when panel was replaced Staff unfamiliar with the replacement panel Sounders too quiet

13 FIRE INVESTIGATION Police decided to use multi-agency approach Police Officers, forensic scientists / photographers Fire Service investigators Private sector (Burgoynes) HSE

14 BENEFITS Police forensic facilities and evidence gathering Fire Service experience fire fighting and development Private sector experience in science and engineering HSE labs and expertise

15 FIRE INVESTIGATION Area of origin Cause of fire Smoke spread Lessons learned

16 ORIGIN Evidence gathering Observations photograph and sketch Reconstruction replace items which have been disturbed Excavations sift through the debris Witness accounts

17 ORIGIN Items that were considered Areas of greatest charring -duration Directional char patterns -spread Available fuel types and quantities degree of damage

18 ORIGIN Items that were considered (cont) Availability of air / drafts Mechanisms of fire spread (explosions) Effects of electrical arcing activity Witness accounts Alarm logs (none) CCTV

19 ORIGIN Determining the area of origin Construct hypotheses that fit the evidence Test each hypothesis Identify which hypotheses stand up to scrutiny Reject those that do not Led us to the cupboard

20 The cupboard

21 ORIGIN The conclusions The fire started in the cupboard The fire probably started to the left hand side of the cupboard Electrical arcing evidence was consistent with the fire starting at or below about half way up the cupboard

22 CAUSE Determining the cause Identify potential sources of ignition Construct hypotheses that fit the evidence Test each hypothesis Identify which hypotheses stand up to scrutiny Reject those that do not

23 CAUSE Potential ignition sources Deliberate Cigarettes /smoking materials Electrical mechanisms Other undeclared / exotica

24 CAUSE Evaluation of ignition sources No evidence of deliberate / did not fit evidence Smokers present but did not fit evidence No remains of other undeclared / exotica, and / or did not fit evidence Significant electrical evidence arcing / damage patterns

25 The distribution board

26 CAUSE Evaluation of electrical evidence No evidence outside the distribution board One circuit breaker was different added late Arcing occurred at a busbar (main conductor) Arcing occurred at a cable to the laundry

27 The circuit breaker

28 The circuit breaker

29 The circuit breaker fixed contact

30 The circuit breaker moving contact

31 CAUSE Conclusions re the breaker It was a different make to the others The materials reacted differently to fire It complied with relevant standards It was incorrectly installed The error was not detected or ignored

32 Arcing at the busbar

33 Arcing at the cable V

34 CAUSE Investigation of the arcing Arcing can cause fires Fires can cause arcing Chicken or egg?

35 Electrical sequence logic Meter Fusebox or consumer unit ON/ OFF RCD Cutout Fuse Neutral Link Earth Socket 1 Plug & Fuse Socket Appliance switch switch Socket Socket

36 CAUSE Conclusions re the arcing Busbar arcing did not precede that at the cable Cable arcing preceded that at the busbar Any circuit breaker electrical trip must have occurred after the cable arced THE ARCING AT THE CABLE WAS 1ST

37 CAUSE Evidence re the cable that arced The sheath had been cut back too far The edge of the penetration was not protected The core insulation was probably damaged on installation The cable was incorrectly installed The error was not detected

38 CAUSE The conclusions Arcing activity occurred at the cable Incendive sparks were ejected Combustible materials were ignited as a result of the arcing activity

39 SMOKE SPREAD The concerns Deaths were attributable to smoke inhalation Smoke spread further than might have been expected

40 SMOKE SPREAD Pertinent factors include Discovery of the fire Actions following discovery The construction of the building

41 SPREAD From the cupboard Along Zone 3 corridor Into bedrooms Through a fire door to Zone 2 Along ductwork between Zone 3 and 2 Into and throughout the roof space

42 SPREAD Aerosols in the cupboard blew doors open Bedroom doors open / did not have closers A fire door was blown open and stuck Ductwork did not have smoke dampers Roof space fire barriers compromised

43 VERIFICATION Fire tests of cupboard and associated corridor Simulating electrical faults Checking fire resistance Smoke spread tests Aerosol explosion tests

44 LESSONS Equipment Electrical installation by qualified staff Fire zones to match fire barriers Ventilation is not to compromise fire barriers Clear fire alarm mimics / zone descriptions Fire alarm panel memories are advantageous

45 LESSONS Organisation Inspection and test per IET guidelines BS7671 Inspection and test of fire alarm systems to include zone checks / test after changes Storage of aerosols to be appropriate Staff training to take account of fire alarm system changes

46 Any Questions?