Authors: N.M. Uddin, M.R. Nyden
Affilation: National Institute of Standards and Technology, United States
Pages: 523 - 526
Keywords: nanoparticle, release, environment char
Studies are being conducted to understand the potential hazards associated with burning materials containing carbon nanotubes (CNTs) and nanofibers (CNFs) either in the process of incineration or in accidental fires. Some of the important questions that need to be answered are: 1) are significant amounts of CNTs and CNFs released into the environment (in addition to soot, which is a ubiquitous byproduct of gas phase combustion) when nanocomposite materials are burned? 2) if so, under what circumstances are these nanoparticles emitted and 3) what are the size distributions, morphologies, and chemistries of the released nanoparticles? Initial measurements were conducted to determine whether CNFs are released into the environment when polyurethane foam (PUF) containing these nanoadditives are burned under well ventilated conditions. Microscopic analyses of particulates in the fire smoke indicated that the CNFs present in the foam were effectively destroyed in the flames. However, high levels of nanoparticles were detected when the residual char was disturbed by air currents or mechanical forces. Thus, it appears that the major hazard for CNF exposure during well-ventilated burning arises from agitation of the residual char, rather than from the fire smoke.