Fire Investigation

I want to ensure that we are all on the same page here. Let me break it down James Brown style.

Places, People, Names and other specific information is deliberately made anonymous here to protect those very things. Some details are altered slightly to ensure that my anonymity and others' remains in place. This blog's purpose is to share my experiences and training for those who are interested. I will not use this blog as a platform for abuse of the Establishment or to reveal details of incidents that have occurred where I work.

Righty oh. We've cleared that up, so lets talk business.

I was lucky enough recently to undergo some further training. I spent a day at a Fire Training Centre. The aim of the day was to put into practise the theory we had learnt on the days before our practical. There were nine of us on the course. It was a scorching hot day and we travelled about an hour or so, behind a tractor, to the centre.

We were split into two groups, one of four and one of five. I was with the group of five.

I had only met one of the other CSIs previously. The centre was a fair size. It was home to the administration headquarters for the local fire service. There was a distinct smell of charred metal containers.

As we rounded the corner, there were ten or so firefighters stood in a semi circle, there appeared to be an instructor in the centre who was talking to them.

We were invited to watch the demonstration of a back draft.

In simple terms, this is a situation that can occur when a fire is starved of oxygen but the gases and fuel within the fire remain at a very high temperature. When oxygen is reintroduced, say by the opening of a door or smashing of a window, then combustion will restart. This normally occurs with an explosive effect, flames and smoke can often be seen to exit the room or house through the door or window, rapidly.

See this Youtube video for a visual demonstration

We watched the demonstration and we all stank of smoke.

We split off into our groups and were given our scenarios.

There had been a report that some masked offenders had stolen a car, a Volvo estate, colour green. They had used it as a getaway vehicle after an armed robbery at a local premises. The vehicle was then reported to be alight and the fire service have attended and extinguished the fire.

I was in a group with four CSI Girls, lucky me.

The car had been placed by a fork lift truck in a small area for us to work on it.

We found out afterwards that a small amount of white spirits had been used to accelerate the fire on the front seat. Items were placed in the vehicle so that we could recover them and observe how they were preserved.

It was my task to take the photographs of the vehicle and any exhibits we found during the excavation. I love photography, I have a real passion it for it. I was pleased that I had this opportunity.

We learnt during the theory input that burnt cars present a very real health and safety risk. Some forces have decided that CSIs will not examine vehicles due to the risk involved. The mix of plastics, metals and other components provide a risky cocktail for the examiner. Fluoroelastomers being one of the main risks which produce hydrofluoric acid when subjected to fire.

I have however read a report that suggests the risk from Fluoroelastomers and the subsequent hydrogen fluoride gas (which condenses to hydrofluoric acid) is minimal in motor vehicles.

We all suited up in Tyvek white suits. It was a scorching hot day. I wore normal rubber gloves to keep my hands and ultimately my camera clean. The CSI Girls wore thicker protective gloves.

I took photographs of the vehicle from each corner, using a 18-35mm lens. Photographs are taken to ensure that a true and accurate record is made of the vehicle before we disturb the scene.

Once I photographed each corner, ensuring that the registration was captured in each, I took a photograph from an elevated position to capture the roof. The roof had suffered a lot of fire damage, the sun roof had acted as a chimney and the glass had all but gone.

I then photographed in each door starting at the driver's door (front offside) and worked my way around. Photographing into a car can be problematic with the flashgun on the hotshoe as the flash usually casts shadows into the vehicle where the light catches the door frame. I took the flashgun off the hotshoe and used a cable. I could then position the flashgun in a suitable place to illuminate the interior sufficiently.

I took my gloves off, they were dripping with sweat. I could feel that my legs were wet with sweat also. Not cool. I made sure I drank lots of water. I hate drinking water, it's such a boring drink!

There was a distinct smell of charred items. The car's insides were black. This was a result of the interior burning and the deposition of soot from the fire and smoke.

Most of the windows were broken. We learnt how to tell if the window was broken before or during the fire. When firefighters extinguish a fire, water from their hoses cause the glass to cool rapidly and this can cause the glass to break, this is known as thermal shock. The glass looks like bubble wrap. When it breaks, the edges are smoother than a normal broken window.

Once the photos were taken of the vehicle as we found it, we began to excavate the debris. We used an assortment of tools. Most of the evidence was likely to be under the first layer of debris, as this top layer is likely to be bits that have fallen during the fire, parts of the roof, glass and fabric etc.

All of the material that was taken from the vehicle was transferred into a large bucket. This needed to be double checked, we had to ensure there were no items of evidential value within the debris. The debris was sieved into another bucket and a magnetic wand was also used to detect any items of importance.

Each of the CSI girls took a door each and began hacking away. With care, of course.

There were a number of items in the vehicle in various places and the practical assessment was aimed at us recovering all of the items.

On the back bench seat was a DVD player. The outer casing had melted and it was black. I turned it over and the underside was as it was when new. I was surprised. I could see the serial number and the model numbers on a sticker. I photographed the sticker using my macro lens.

I love my macro lens.

The front seats were reduced to the frames. You could see the springs where the cushions would normally be. The back seat was charred but generally had remained intact.

I swapped with one CSI Girl and started excavating the driver's seat and foot well.

I was convinced that we were going to find a firearm within the vehicle and looked everywhere.

When I was digging the debris from under the seat, I found a set of Volvo keys. The leather fob was in pristine condition. This was surprising as everything around it was burnt to a crisp. The way in which the bunch of keys were placed, protected the fob. It was covered in a dark yellow sticky substance, a product of the burnt interior I expect.

I soldiered on and used a very large knife to cut the carpet from the vehicle. The rubber floor mat had protected the floor very well. When I cut the carpet, I found what appeared to be a shotgun cartridge. It was surrounded by melted debris. I couldn't separate it from the debris but could very clearly see the bottom. I used my macro lens to photograph the base. The firing pin mark was clearly visible.

We worked on the vehicle for just over an hour and a half. We managed to recover cigarette ends (fully preserved!) keys, a bottle of accelerant, a DVD player, a Coke can, a spoon and a magazine which had preserved a CD within it.

We didn't find a firearm.

The car was in a bad way when we got hold of it and to say it was any better when we finished would be a lie. It was cleaner though. All of the debris had been stripped right out. Wind the clock back a few thousand miles and give it a polish and it'd be on the second hand car dealership forecourt in minutes for £975 with a free tank of petrol.

My force policy is not to examine vehicles that have been burnt out unless they are involved in a serious or major crime. I understand the reasoning behind it. I did however, enjoy ripping that poor little Volvo to pieces and collecting evidence.

It must be a guy thing, breaking and destroying things. I loved it.

If fingerprints were a requirement of the interior, then there is also a chemical treatment that allows soot to be removed from surfaces to allow for fingerprinting. Some of the items we recovered may have been subject to this once they reached the lab.

We had to package an item each, which had been recovered from the vehicle. The general rule is to package anything from a fire scene into nylon bags as any accelerant or fluid will not seep through the nylon as they would in a normal plastic bag. There is a method of securing the opening of the bag, known as a swan neck, which prevents leakage also.

We had a debrief and completed another exercise. We had lunch on the local fire service which was delicious and we headed back to watch the football.

Its been really busy at work recently. We have had a large number of major incidents and everyone has been rushed off their feet dealing with them. Its nice to work with a team that really pull together when the workload increases. I'm lucky to be where I am.

I would like to take the opportunity to wish PC David Rathband well and let him know that Police Officers and Staff across the country are thinking of him. Good luck.

Until next time.


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