Chemical plants and storage facilities handling and storing substantial amounts of hazardous substances, e.g. pesticides, are quite common in most countries. Fires involving chemicals seem to be the more serious hazard from these activities. The project was initiated to assess the potential consequences from fires at chemicals plants and storage facilities. As part of the project, substances and materials were classified based on a number of characteristics comprising parameters such as ignitability, heat release, burning rate, smoke evolution, products of combustion and the influence of packaging materials on the combustion products. The source characteristics were described by parameters obtained by carrying out combustion experiments at various scales and by studying the effects of scaling.
The role of SP in the TOXFIRE project was to carry out controlled large-scale combustion experiments with the amount of material (chemicals) burned in the 100 kg range. The real challenge was to achieve conditions yielding under-ventilated, i.e. oxygen-depleted, combustions. Two types of experimental set-ups were used. Most of the large-scale experiments were carried out in the ISO 9705 room with the chemicals in a steel pan during the combustion experiments. This test arrangement was considered to be the optimum - large enough in scale to represent full-scale conditions and, moreover, sufficiently controlled to provide good and repeatable test results. A few tests were performed in an even larger scale test enclosure, 256 m3, that was built to allow "real" storage configurations. These tests were performed as a complement to the ISO 9705 room tests, to give an idea of the influence from sample configuration and room size on the fire characteristics, in particular on the nature of the products of combustion.
Five different materials were used in the large-scale tests. Great care had to be exercised in the selection of compounds since they were to be used in rather large quantities indoors and combusted under poor ventilation conditions. To obtain reasonable complexity in the composition of the smoke gases, the elemental composition, in addition to just carbon-hydrogen-oxygen, included nitrogen, sulfur and/or chlorine, respectively, in the materials selected for large-scale combustion. The materials studied were polypropene (PP), Nylon 66 (Ny), tetramethylthiuram monosulfide (TMTM), 4-chloro-3-nitrobenzoic acid (CNBA), and chlorobenzene (CB).
Storage configuration tests were performed with four of the substances used as fuel.
Four individual experiments were performed in the ISO 9705 room on each of the materials. In the storage configuration test enclosure, one configured test was performed on each material, with the exception of chlorobenzene. In addition, two open pool combustions (polypropene; chlorobenzene) were carried out in that larger test facility.
During these tests, all the common fire test parameters were measured, such as temperature, heat release rate, smoke production rate, etc. In addition, extensive measurements were carried out to characterise the smoke gases.
Published SP reports about the project
Details about the experimental set-ups, experimental procedures, measurement techniques, and results are given in the following SP REPORTS:
Månsson, M., Lönnermark, A., Blomqvist, P., Persson, H., and Babrauskas, V. "TOXFIRE - Fire Characteristics and Smoke Gas Analyses in Under-ventilated Large-scale Combustion Experiments", SP REPORT 1996:44, ISBN 91-7848-649-1.
Lönnermark, A., Blomqvist, P., Månsson, M., and Persson, H. "TOXFIRE - Fire Characteristics and Smoke Gas Analyses in Under-ventilated Large-scale Combustion Experiments: Tests in the ISO 9705 Room", SP REPORT 1996:45, ISBN 91-7848-650-5.
Lönnermark, A., Blomqvist, P., Månsson, M., and Persson, H. "TOXFIRE - Fire Characteristics and Smoke Gas Analyses in Under-ventilated Large-scale Combustion Experiments: Storage Configuration Tests", SP REPORT 1996:46, ISBN 91-7848-651-3.
Blomqvist, P., Lindberg, P., and Månsson, M "TOXFIRE - Fire Characteristics and Smoke Gas Analyses in Under-ventilated Large-scale Combustion Experiments: FTIR Measurements", SP REPORT 1996:47, ISBN 91-7848-652-1.
Månsson, M., Isaksson, I., and Rosell, L. "TOXFIRE - Fire Characteristics and Smoke Gas Analyses in Under-ventilated Large-scale Combustion Experiments: Adsorbent and soot measurements", SP REPORT 1996:48, ISBN 91-7848-653-X.
Lönnermark, A., and Babrauskas, V. "TOXFIRE - Fire Characteristics and Smoke Gas Analyses in Under-ventilated Large-scale Combustion Experiments: Theoretical Background and Calculations", SP REPORT 1996:49, ISBN 91-7848-654-8.