Early one November morning in Saudi Arabia, a police officer in a nearby mosque observed smoke coming from a carpet warehouse. Heavy black smoke poured out from the door openings and the joints in the warehouse walls. Civil defence were called to the site to deal with the fire and they managed to extinguish the fire in quickly. Warehouse employees were instructed to preserve the scene and to not remove any items that might be useful in the ensuing investigation.
Not long after the civil defence left, heavy, thick black smoke was seen filling the entire warehouse again. Civil defence was called back and again dealt with the fire. This time, civil defence officers instructed the warehouse workers to move all carpet rolls in the area of the fire to a yard outside the warehouse. As no workers were at the warehouse at the time and all electrical fixtures were turned off, the cause was puzzling investigating officers who reported that they were unable to determine the exact cause, and incendiary causes remained under investigation.
Expert Involvement
CEERISK’s expert fire investigators arrived to conduct an investigation into the cause & origin of the fire. After interviewing witnesses who included the warehouse manager and workers, they reviewed the history of the building. They were able to determine that the property was well-maintained and all electric wiring and firefighting systems were inspected annually, to positive results.
CEERISK investigators proceeded to examine the scene of the fire and were able to quickly determine the general area of origin. There were two distinct areas where burn and heat patterns were observed. The first set of burn patterns corresponded to where the carpet rolls were stored before they were moved outside. The second set of burn patterns were identified on the upper section of the wall and the roof steel beams directly above the rolls of carpet. Neither one of the two areas had any potent ignition sources that could explain ignition of carpet rolls. No electrical wiring or other heat sources were present at either area.
As the investigators climbed to the roof of the warehouse, they observed significant amounts of heat damage to the plastic sheeting used under the roof sheet metal panel. This damage corresponded to the areas inside the warehouse where the burn patterns were observed.
The investigation continued outside the warehouse, where our investigators noticed empty cinder block buildings used as workers’ accommodation. They also noticed areas on the wall of these buildings that had remarkable burn patterns. Around the area, charred remains of wood and burned garbage were found.
Bridging the Gap
Experts concluded that the fire started on the roof first. As a result, insulation fixed to the underside of the roof panels ignited and started dropping down to the warehouse floor. Burning debris from the roof landed on the carpet rolls igniting them.
There was no evidence of accidental heat sources that could have ignited the rolls of carpet or the insulation on the underside of the roof panels. After further investigation into the weather conditions on the day of the fire, especially the wind speed, our fire investigators started considering the remains of burnt wood and rubbish outside the warehouse, next to the adjacent workers’ accommodation.
Could a burning ember from a nearby garbage fire explain the fire inside the warehouse? Confirming the windy conditions on the night of the fire provided, the investigators had the evidence they need that the cause of the fire in the warehouse was a burned ember flown by wind to the roof of the warehouse, where plastic sheathing was ignited along with the combustible insulation fixed to the underside of the roof. Falling burnt debris landed on carpet rolls stored underneath and caused a second fire, which continued to smoulder and cause a second fire later that day even after being dealt with by civil defence.
