Generation and transport of smoke components

Smoke is a mixture of gases, vapors, and suspended particulate matter, or aerosols. The nature of the aerosol component of smoke can play a significant role in its deposition in the fire environment and in its lethal and sublethal effects on people. This paper presents the current state of knowledge about smoke aerosol phenomena that affects smoke toxicity: soot generation, fractal structure of soot, agglomerate transport via thermophoresis, sedimentation, and diffusion, agglomerate growth through coagulation and condensation, and the potential for the aerosols to transport adsorbed or absorbed toxic gases or vapors into the lungs. Tables are included for measured smoke yields and aerodynamic particle sizes, equations and references are provided for the smoke agglomerate transport properties and wall loss, and key literature references are provided for adsorption of irritant gases on soot particles and water droplets and the toxicity of nanosize particles.