1. SUMMARY 1.1 Identity, physical and chemical properties Carbon/graphite fibres are filamentary forms of carbon produced by high-temperature processing of one of three precursor materials: rayon (regenerated cellulose), pitch (coal tar or petroleum residue) or polyacrylonitrile (PAN). Nominal diameters of carbon fibres range between 5 and 15 µm. Carbon fibres are flexible and electrically and thermally conductive, and in high performance varieties have high Young's modulus (cooefficient of elasticity measuring the softness or stiffness of …showed first 75 words of 1957 total…

…showed last 75 words of 1957 total…category until data indicating a lesser degree of hazard become available. 4. Populations potentially exposed to respirable organic fibres should have their exposure monitored in order to evaluate exposure levels and the possible need for additional control measures. 5. Populations identified as being those most exposed to respirable organic fibres should be enrolled in preventive medicine programmes that focus on the respiratory system. These data should be reviewed periodically for any early signs of adverse health effects.