RESUMO
In 1985 the Health and Safety Executive set a gravimetric Control Limit for airborne Man-Made Mineral Fibre and in 1987 a respirable fibre number Recommended Limit for Superfine MMMF. A limited investigation was carried out of the use of glass and ceramic fibre products used as protection against welding 'batter' and oxyacetylene welding flame. Airborne fibre levels are compared with the Occupational Exposure Limits.
Assuntos
Poluentes Ocupacionais do Ar/análise , Compostos de Cálcio , Poeira/análise , Silicatos , Ácido Silícico/análise , Dióxido de Silício/análise , Soldagem , Humanos , Concentração Máxima Permitida , Tamanho da PartículaRESUMO
Oxygen isotope analyses of planktonic foraminifera from the Red Sea and Gulf of Aden indicate that during periods of maximum continental and polar glaciation in the late Pleistocene, the Red Sea was subject to strong evaporation. Between glacial maximums the salinity of the Red Sea was equal to or below that of the open ocean. This suggests that high-latitude glacial periods corresponded in time to interpluvial stages in the present-day desert belt of northern Africa, whereas high-latitude interglacial periods coincided with pluvial stages.