SUMMARYIsocyanates, aminoisocyanates and amines were quantified from the combustion of 24 different materials or products typically found in buildings. Small-scale combustion experiments were conducted in the cone calorimeter, where generally well-ventilated combustion conditions are attained. Measurements were further made in two different full-scale experiments.Isocyanates and amino-compounds were sampled using an impinger-filter sampling system with a reagent solution of di-n-butylamine in toluene. Filter and impinger solution were analysed separately using LC-MS technique. Further the particulate distribution in the smoke gases was determined by impactor technique, and selected gaseous compounds quantified by FTIR.It was found in the small-scale that isocyanates were produced from the majority of the materials tested. The highest concentration was found for glass wool insulation, and further high concentrations were found for PUR products, particleboard, nitrile rubber and melamine. Lower concentrations were found for wood and cable-products. Amino-isocyanates and amines were generally found from PUR products only.The distribution of isocyanates between the particulate-and fluid phases varied for the different materials and a tendency to enrichment of particles was seen for some of the materials. Further, when comparing the potential health hazard between isocyanates and other major fire gases (based on NIOSH IDLH-values) it was found that isocyanates in several cases represented the greatest hazard.
SUMMARYSmall combustion generated particles are known to have a negative impact on human health and on the environment. In spite of the huge amount of particles generated locally in a fire accident, few investigations have been made on the particles from such fires. In this article, 24 different materials or products, typically found in buildings have been exposed to burning conditions in order to examine their particle generating capacity. In addition, a carbon fibre based composite material was tested in order to investigate if asbestosresembling particles could be generated in a fire situation.The majority of the experiments were performed in the small-scale cone calorimeter, and some further data were collected in intermediate scale (SBI) and full scale (room-corner) tests. Additional testing of the composite material was made in a small-scale tubular reactor.The amount of particles and particle size distributions were measured by the use of a low-pressure impactor and particle aerodynamic diameter sizes from 30 nm to 10 mm were measured.The results from the project show that the yield of particles generated varied significantly between materials but that the shape of mass and number size distributions were very similar for all the materials tested. The maximum amount of particles was obtained from materials that did not burn well (e.g. flame retarded materials). Well-burning materials, e.g. wood materials, tend to oxidize all available substances and thereby minimize the amount of particles in the smoke gas. It was found that asbestos-resembling particles could be produced from under-ventilated combustion of the composite material tested.
SUMMARYInhalable carbon fibres have been suspected to pose similar threats to human health as asbestos fibres. It is well-known that fibres having a diameter of less than 3 mm might be inhaled and transported deep into the human respiratory system. Some composite materials use carbon fibres as structural reinforcement. These fibres do not pose any risks as such as they are firmly connected to the laminate and surrounded by a polymer matrix. Also, these fibres typically have diameters >6 mm and thus, are not inhalable. However, if the material is exposed to a fire, the carbon material might be oxidized and fractionated and thereby, inhalable fibres might be generated into the fire smoke.The capability of carbon fibre-based composite material to produce dangerous inhalable fibres from different combustion scenarios has been investigated. It was found that the risk of fires generating inhalable carbon fibres is related to the surface temperature, the oxygen level and the airflow field close to the material surface. The temperatures necessary for oxidation of the carbon fibre is so high that it is possible that only a flashover situation will pose any real danger. Other possible danger scenarios are highly intense fires (e.g. a liquid fuel fire), or situations where structural damage is part of the fire scenario.
Reduced weight makes use of fiber reinforced polymer composite desirable in maritime construction applications. Exterior ship surfaces in combustible materials are although not covered by fire safety regulations and their fire protection is therefore a key issue. This paper reports how SP FIRE 105, a standardized test method for testing reaction to fire properties of façade systems, was adjusted and used to evaluate the potential for fire growth on external combustible ship surfaces; in particular fiber reinforced polymer composite surfaces protected with active or passive measures. The trials show that the test method is highly suitable but that some adjustments could be made to reduce uncertainties; in particular to use a gas burner instead of a heptane pool fire source and to add a strong criterion for when to activate active measures. Further efforts should also be made to develop suitable performance criteria, which were suggested to be based on the produced heat and the gas temperatures at the top of the panel.
SUMMARYA series of tests including seven different materials and products have been conducted using a controlled equivalence ratio tube furnace test method. The main objective of the tests was to determine yields of fire-generated products at defined combustion conditions.The tube furnace test method was set up and run in close agreement with that described in BS 7990:2003. At the time of experimental work the new tube furnace method was in the process of becoming an international standard. It was thus of interest to make an assessment of the capability of the method for determining production yields of important toxic fire products from different types of materials and products.The test series included solid wood, flexible polyurethane (PUR), fire-retarded rigid PUR, a polyvinyl chloride (PVC) carpet, a high-performance data cable with fluorine-containing polymer matrix, a PVCbased cable sheathing material and fire-retarded polyethylene cable insulation material. Duplicate tests were generally conducted at both well-ventilated and vitiated combustion conditions with these materials.The smoke gases produced from the combustion were quantified for inorganic gases by FTIR technique in all tests. A more detailed analysis of the smoke gases was conducted for some of the materials. This extended analysis contained a detailed assessment of organic compounds including, e.g. volatile organic compounds, isocyanates, aldehydes and polycyclic aromatic hydrocarbons. The analysis further included measurement of the size distribution of fire-generated particles for some of the materials.The quantification of toxic inorganic gases produced by combustion at both well-ventilated and vitiated conditions was successful regarding repeatability and stability. Typical yields for the two fire stages investigated were determined for a wide range of materials and products. The detailed analysis of organic * Correspondence to: Per Blomqvist,
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