2nd International Fire Information Conference
held on Thursday, 30 May and Friday 31 May 2002
at the Imperial Hotel, Russell Square, London, 10.00 - 17.00
The Information Needs of a Fire Investigator
by Dr Roger Berrett
Forensic Science Consultant in Fire and Explosion Investigation
9 Heron's Croft, Weybridge, Surrey, KT13 0PL
Tel & Fax 01932 859430
Fire Investigation is a very broad subject. For the purposes of this short presentation I will confine my comments to the traditional 'origin and cause' aspects of the subject or, in other words, the where, what, how and when considerations. The subject also encompasses the so-called 'dispersed phase' explosions but not 'condensed phase' ones.
Fire investigators should be omnicompetent. Ideally, they should have experience and knowledge of, and be trained in subjects as diverse as, fire fighting, natural sciences (including analytical methods), engineering, forensic medicine, police procedures (including interview techniques), various aspects of criminal and civil law and, perhaps, psychology.
To the best of my knowledge no such person exists, and, therefore the qualifications, and the training of a fire investigator are a compromise. In principle it does not matter who investigates fires as long as they have an appropriate background, qualifications and training to carry out a competent examination of the fire scene and, most importantly, be able to present such evidence in a court of Law. This may be a Coroners' Court in the case of fatalities, a Magistrate's or Crown Court in criminal cases or a Civil Court in the case of insurance claims and the like.
By way of background, there are 67 Fire Brigades in the United Kingdom. They attend over half a million fires annually including 800 deaths and 17,000 casualties . It is also interesting to note that, according to the results from the "British Crime Survey of fires in the home"  there were about 75,000 home fires in England and Wales but the proportion attended by fire brigades was estimated to be less than 20%. Two thirds of these fires started in the kitchen, the majority of which were caused by cooking appliances.
Leaving aside the obvious kitchen fires and other obvious ones, it is generally accepted that over 50% of significant fires are deliberately started but the conviction rate for Arson is less than 1%.
The Fire Brigade
Firefighters in the UK have no statutory obligation to investigate the origin and cause of fires. However, they are expected to determine the supposed cause of the fire and to complete a "Fire Data Report" form (FDR/1). Essentially this form is a Fire Prevention tool and is subsequently used to provide information for Government (Home Office) annual Fire Statistics. If the fire is thought to be suspicious in nature, then they do have an obligation to notify the police.
There are only a few fire brigades that have dedicated 'Fire Investigation Teams', for example, London and West Midlands. In general, 'Fire Investigation' normally comes under the management umbrella of 'Fire Safety and Fire Prevention' and as such tends to be the poor relation. Moreover, in times of Government cuts in expenditure, Fire Investigation tends to be the first area of fire brigade activity to be curtailed. Politically, there appears to be an emphasis towards 'human life safety' at the expense of fire safety in general.
If a fire is thought to be "suspicious", the investigation of it then becomes a police responsibility. Initially a Scenes of Crime Officer (SOCO) should examine the fire and, if the evidence is factual, they should be able to deal with it. On the other hand if there are interpretive matters to be addressed then a Forensic Scientist should be called in. There are Home Office Guidelines on the procedures that should be adopted in respect of this .
The Forensic Scientist
The Forensic Scientist, who may be called in by the police, is usually from the Forensic Science Service (in effect a Home Office Agency). In practice this means that the police have to pay directly for their services. There is sometimes a reluctance to call them in which can present problems at a later stage.
The 'information thread' runs through virtually all aspects of fire investigation from beginning to end.
In the first instance the investigator will need to have basic information regarding the location of the incident, when the fire brigade were called and their time of arrival, what they observed and how they fought the fire, and information from eye witnesses.
The properly qualified fire investigator will be armed with a vast amount of information such as the various aspects of fire science, the collection and the appropriate packaging of appropriate exhibits to preserve the integrity of such evidence and an appreciation of what can be achieved from the vast array of analytical techniques that are available in a well equipped forensic science laboratory.
Fire Investigation is not a simple matter of 'ticking boxes' and ending up with an answer. But it is helpful to have some sort of strategy based on the following eight headings.
Safety is paramount. In cases involving unsafe structures then information from a surveyor may be sought. It may take days or weeks for a structure to be 'made safe' and occasionally this might not be possible and the cause of the fire cannot be determined.
Background information pertaining to the circumstances prior to the fire and the fire itself.
Here the fire investigator is simply accumulating Information by various means such as talking to appropriate witnesses when possible, observing the extent and severity of the fire damage and making an assessment of where the fire might have started. In the case of a small house fire this process might take only a few minutes but in the case of a large industrial premises it might take as long as a day or two and may require an understanding and information of the processes that had been in progress prior to, or at the time of, the fire. Good science is based on observation.
Having established from observations the area of origin of the fire, the purpose of this exercise is to remove the loose debris and carefully 'dig'. This is akin to Archeology but with a somewhat shorter time frame! Here we are seeking information as to what materials were in the area of interest and then to make an assessment as to what could have been the ignition source. Again, in a small 'house fire' this process may be relatively non labour intensive but it still has to be done meticulously. On the other hand, in the case of a large warehouse, the task can be lengthy and sometimes difficult but it has to be done for a meaningful assessment to be made with regard to the cause of the fire. As I write, a colleague of mine is 'digging out' the debris from a perfume factory in the Middle East at a temperature of 45 degrees centigrade with the help of a local 'task force' and vast quantities of bottled water!
In general, this activity pertains to the smaller type fires where the fire brigade (occasionally for good reason) have removed the entire contents of the premises to the outside of the building during, or at the latter stage of, the fire fighting. In such instances it is invariably helpful to replace these items, such as charred furniture, as far as is possible. Such an exercise can often yield valuable information as to precisely where the fire had originated, what material had been first ignited and perhaps what might have been the ignition source.
Having done the manual work it is likely at this stage that the fire investigator can evaluate all the information gleaned and arrive at a scientific and valued assessment of what it all means.
Now comes the difficult bit. One has to convince the client of the outcome of the investigation, which is why the information that one has obtained, and derived, must be sound. This communication may be done verbally or by way of some form of report or statement which is yet another skill that the fire investigator needs to acquire through training and experience.
All the various strands of the information need to be well thought out, structured and brought together by way of a conclusion. It is often the case that only the conclusion of a report is actually read by the client.
There are many times when the fire investigator will need further information, over and above, what they might have at their 'finger tips' in order to evaluate all the information that they have derived and to form a conclusion as to the cause of the fire.
This talk will discuss some of these by way examples that will include such topics as:
- so called 'hot work': welding/cutting, disc cutters (abrasive wheels), propane gas torches;
- various industrial processes: polyurethane foam production and the likelihood of so called 'spontaneous combustion'; and,
- 'dispersed phase' explosions: dust, natural gas, petrol, and other hydrocarbons.
- CCTV and digital cameras
The 'Downside' and the 'Upside' of Information
There are many myths and legends concerning 'fire science' and 'fire investigation' and unfortunately some of these still persist today. Notwithstanding this, much effort has been put in to attempt to dispel some of these. The 'media' does not help in this respect. We still see clips on 'London's Burning' of the 'proverbial' cigarette end being thrown into a pool of petrol and it going 'whoosh' or even 'whoomph'! We still have programmes and books on 'Spontaneous Human combustion' (SHC). There are many more; some of these will be discussed in the talk.
Most fires are 'solved' by a combination of physical (scientific) and witness information.
Occasionally, one means or the other solves them. The 'Kings Cross' fire and the 'Windsor Castle' fire are good examples of these two extremes. Both will be discussed by way of example to illustrate this point.
Got there in the end! Having said that, the important point is that the user needs to have such information, as is available, regardless of how and in what form it arrives. One disquieting feature of all this e-information is that, in general, it effectively covers only the last 10 years or so. It seems to me that this might tend to make research students in the subject somewhat 'sloppy', and perhaps degrade some of the excellent work done, say 30 or 40 years ago (Rasbash and all that), to say nothing of Michael Faraday over 100 years ago!
Apart from 'fire science' and 'fire investigation there is often much information to be gleaned from other scientific disciplines from a fire scene. Some of these 'evidence types' will be discussed.
1. Summary fire statistics United Kingdom 1998 Statistical Bulletin Issue 8/00.
2. Fires in the home in 1998: results from the British Crime Survey; Statistical Bulletin 9/00.
3. Home Office Circular No. 44/2000
Cooke RA and Ide RH. Principles of Fire Investigation. Institution of Fire Engineers, Leicester, 1985
DeHaan JD. Kirk's Fire Investigation. 4th edition. New Jersey, Prentice-Hall, 1997.
NFPA 921. Fire and Explosion Investigations, 2001 Edition.
The Chemical History of a Candle, Michael Faraday: ISBN: 0-87797-209-5