Hazards presented by pyrolysis and combustion products during laboratory experiments and real incidents

Abstract

Heat, flame, smoke and fire gases are responsible for the vast majority of fire deaths and injuries and are all products of the chemical and physical processes that occur within fire. This is well known and supported by fire statistics but current fire safety does not directly consider these factors and the hazard they may pose to life. The aim of this thesis is to bring together knowledge from fire science with evidence from fire investigation to provide a way forward for improving fire safety and protecting life using sound scientific principles.

A number of major fires and the associated large scale fire reconstructions carried out as part of their investigation have been analysed to assess the way in which polymeric materials contribute towards the overall hazard and whether there are other factors tending to contribute to the hazard. The Stardust Disco fire highlighted the importance of lining materials in their contribution to both rapid fire development and toxicity. Maysfield Leisure Centre demonstrated the link between functional groups in polymers and the major toxicant likely to then contribute to the developing hazard. Harrow Court showed how a modern incident able to develop to flashover would produce a dramatic change in conditions, capable of overcoming fire fighters as well as civilians. Rosepark Care Home demonstrated the importance of simple fire safety measures such as the closing of doors in keeping products of combustion away from relevant persons. The Lakanal fire highlighted the potential complexity of these sorts of incidents and the way in which they tend to be the result of a large number of “things going wrong” all at once. The fire at Atherstone on Stour revealed the potential for rapid fire development to take place across very large environments, again sufficiently quickly to overcome attending fire fighters.

The work carried out has demonstrated the intrinsic link between the burning properties of materials with their toxicity, which are then further influenced by the way in which an environment can influence ventilation conditions, thermal insulation and pathways for fire to spread and impose hazards upon people in relevant areas. Fire safety has developed in such a way that flammability and toxicity no longer appear to be considered together, but the findings from the incident analyses indicate there appears to be a need to bring the subjects of toxicity and general fire safety back together.