Toxicity of Nanoparticles


Polymer-nanocomposite materials show excellent potential in real-scale fires, but perform poorly or fail small scale standard flammability tests. This occurs because real scale fires are difficult to replicate on a small-scale, though it is these fires (large-underventilated) which account for the majority of fatalities in fire, with high toxic gas. In standard ignitability and flammability tests, nanocomposites often perfom poorly or fail, although they perform well in real-scale tests. For example, the increase in viscosity of molten nanocomposites, such as nylon or polypropylene prevents the material from flowing away from a flame, giving the nanocomposite a higher ignitability index in certain tests.

 

Many nanocomposites show an initial surface flame before they form a ceramicised protective layer, and many show higher yields of carbon monoxide, the major toxic gas in fires, under well-ventilated conditions.


The lack of knowledge about how such low levels of nanocomposite additive can have such large effects on flammability has exacerbated the difficulties in quantifying this improved burning behaviour.


Related Projects


  • Fire Toxicity Assessment

    Death in fire may be caused either by gases which are directly toxic or which cause such irritation that they impair vision and breathing, preventing escape, or by smoke which not only impairs escape ability by visual obscuration, but also contains particulate matter which is sufficiently small to pose a respiratory hazard. Combustion toxicity is highly dependent on fire conditions. It depends on material, ventilation condition, oxygen depletion, and fuel geometry.


  • Toxicity of Nanoparticles


  • Characterisation of Size Distribution



Back

Researchers