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Fire safety or the environment - is it necessary to choose?
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Issue 48: Fire safety or the environment - is it necessary to choose?

By Margaret Simonson McNamee

Awareness of the fact that large fires may present dramatic and persistent adverse effects on the environment has risen since the occurrence of numerous high impact incidents over the past 25 years. These incidents include the Sandoz incident in November of 1986 when a chemical fire in an industrial warehouse near Basel in Switzerland laid waste to the Rhine.1

Traditionally, discussion of the environmental impact of fires has focused on the emissions that fires can cause both to the air, water and soil; but in recent years a new debate has arisen where the impact of chemicals on the environment and the precautionary principle have taken precedence.2

While that debate began in the 70s, it still rages today.3 Most concerning is the polarization in the debate, where environmentalist and fire safety specialists seem to be on either side of the issue. Both groups are inherently interested in safety, but without an accepted model to weigh environmental risks against fire risks, the debate will continue to pit these risks against each other qualitatively rather than quantitatively and resolution of the issue will be difficult.

Fire emissions

Fires produce a complex cocktail of effluents, all with varying modes of action and longevity, toxicity and eco-toxicity. Typically, the impact of fire emissions can be divided into acute and long term effects.

In terms of the environmental impact of fire effluents, long term effects are often more important than acute effects. Traditionally, carbon monoxide (CO) is recognized as the main acute toxicant in fires,4 although numerous other gases can be as potentially important in determining the outcome of any given fire exposure.

Models for assessment of the effects of chemical compounds with an acute effect on people are available in ISO 13571.5 In contrast, large organic species, such as dioxins or polycyclic aromatic hydrocarbons (PAHs) are those species which are thought to have the greatest environmental impact.6

 

A guideline document for the assessment of the environmental impact from fires has been developed in ISO/TC92 SC3/WG6.7 This document presents emission pathways and species of interest from an eco-toxicological point of view. There are, however, no standards available for the quantification of the effect from fires on the environment.

The interaction between a fire and its surroundings (or environment) is illustrated in Fig. 1. This figure shows that there are a number of different emission pathways that allow a fire to impact the environment. The effect of these emissions depends on the transfer mechanism (i.e., emission of gaseous species to the atmosphere, or emissions to the terrestrial or aquatic environment), the susceptibility of the recipient, and on the specific species.8


Fig. 1. Emission pathways (based on Ref. 8).


Assessing the Environmental Impact

Numerous environmental assessment methodologies exist ranging from full life cycle analysis (LCA) tools to less detailed types of environmental assessment tools. Traditionally, these tools assume an incident-free life-cycle of the product or process being evaluated. This means that in the case of a traditional tool, the function of a flame retardant or an extinguishing medium in terms of a potential reduction in the number and size of fires is not included.

In response to the limitations of traditional environmental assessment tools, the Fire-LCA model was first developed in 1995.9,10 The aim was to develop a tool that could be used for making a quantitative comparison of the environmental impact of different fire performance legislations. LCA was chosen as the basis for the development as this is a widely used tool and sufficiently sophisticated to include factors like the effect of the mitigation of fires.

It soon became apparent, however, that this model also has its limitations, and the Fire-CBA model was developed to address some of these limitations.11 These models represent the first attempts to quantify the comparison of risks between fire emissions, flame retardants and the potential impact of the environment.

The Fire-LCA model is best described in Figure 2. The Fire-CBA model can be summarized in Table 1. A full application of the Fire-LCA model can be found in reference 10 and of the Fire-CBA model in reference 11.


Figure 2. Schematic representation of Fire-LCA model.


Module Comment
Production Any additional costs associated with production should be included in this part of the CBA. In some cases, the use of alternative materials can require significant investments by industry which should be included in the cost.
Use The difference assumed in the Fire-CBA does not impact on the costs associated with the use and this will not be included.
Transport As for the use, the costs associated with transportation of the functional unit would not be expected to change through the introduction of flame retardants or other fire mitigation measures.
Destruction Additional costs associated with specific destruction plans could be included in this module, e.g. specific cost programs related to the end-of-life destruction of consumer products. Alternatively, one could consider a worst case scenario with a dedicated, isolated stream destruction of materials containing 'hazardous' chemicals and the cost associated with this.
Fires The cost of extinguishment, sanitation, treatment of injuries and possible deaths should be included in the cost of fires. Indeed, one of the major benefits of the use of a high level of fire safety is the avoidance of fires, reduction in the size of fires that occur and reduction in injuries and loss of lives.
Chemical Exposure This is not strictly a 'module' but related to exposure which can occur connected to chemicals throughout the life-cycle of the product. In the Fire-CBA model, this is focused on exposure to flame retardants.

Table 1. Information requirements for Fire-CBA model.

 

Both the Fire-LCA and Fire-CBA models were developed in an effort to answer difficult questions concerning the relative merits of fire safety and the use of potentially undesirable chemicals. Both models provide a part of the answer but not the whole answer.

Further, as for all complex tools, the models are no better than their input, and the quality of data across the whole life-cycle of a product is generally patchy. There is a need to improve the assessment stages of both models and to develop a global model, capable of taking into account both emissions and their impact, and the societal impact of different regulations and the cost-benefit of one choice against another.

Until such a model has been developed, it is not possible to answer the question of whether the benefits of any individual flame retardant (in terms of enhanced fire safety) outweigh the potential costs of that chemical (in terms of environmental exposure). The development of such a multi-parameter tool is a difficult, but important, task that will require a significant amount of research in the future to realize. Even without such a tool; however, it is not necessary to choose between fire safety and environmental safety. Both must, and can, be protected through the choice of relevant levels of fire safety and the judicious use of chemicals that have been screened and approved by the type of risk assessment commonly used in most developed parts of the world by, e.g. the European Union or the US EPA.

Margaret Simonson McNamee is with SP Technical Research Institute of Sweden


REFERENCES

  1. Suter, K.E., et al. (Guest editor), "Analytical and Toxicological Investigations of Respiratory Filters and Building Ventilation Filters Exposed to Combustion Gases of the Chemical Warehouse Fire," Schweizerhalle, Chemosphere 19(7), pp. 1019-1109, 1989.
  2. Ashford, N., et al., "Wingspread Statement on the Precautionary Principle", Science and Environmental Health Network, 1998.
  3. Babrauskas, V., Blum, A., Daley, R., and Birnbaum, L., "Flame retardants in furniture foam: benefits and risks," Proceedings of the 10th International Symposium on Fire Safety Science, International Association for Fire Safety Science, London, 2011.
  4. Hirschler, M.M., (ed.), Carbon Monoxide and Human Lethality: Fire and Non-Fire Studies, Elsevier Science Publishers, Essex: 1993.
  5. ISO 13571, "Life Threatening Components of Fire – Guidelines on the Estimation of Time Available for Escape Using Fire Data," International Standardization Organization, Geneva, 2007.
  6. Persson, B. and Simonson, M., "Fire emissions into the atmosphere," Fire Technology, 34(3):267-279, 1998.
  7. ISO 26367-1 "Guidelines for assessing the adverse environmental impact of fire effluents - Part I: General," International Standardization Organization, Geneva, 2011
  8. Hölemann H., "Environmental Problems Caused by Fire and Fire-Fighting Agents," Proceedings of the 4th International Symposium on Fire Safety Science, International Association for Fire Safety Science, London, 1994.
  9. Andersson, P., Simonson, M., Stripple, H., and Paloposki, T., "Fire-LCA Guidelines", SP Report 2004:43, SP, Borås, Sweden, 2004.
  10. Simonson, M., Blomqvist, P., Boldizar, A., Möller, K., Rosell, L., Tullin, C., Stripple H. and Sundqvist, J.O., "Fire-LCA model: TV case study", SP Report 2000:13, SP, Borås, Sweden, 2000.
  11. Simonson, M., Andersson, P., and van den Berg, M., "Cost Benefit Analysis Model for Fire Safety: DecaBDE Case Study", SP, Borås, Sweden, 2006.

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