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Occupational exposure limit values for chemicals

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Abstract

A general comment on the concept of occupational exposure limit values for chemicals is made, and several topics related to these limit values are reviewed: the scientific basis for their establishment, the main lists of limit values, the limit values in the European Union and in Spain, the comparison of exposure with limit values and the exposure to several substances.

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... Steps for an effective risk assessment and management in tunnelling operations 1. Hazards Identification: Forecasting the presence of hazardous substances in the rock mass to be excavated; the prediction should be completed with the best estimate of its uncertainty 2. Risk Analysis: Correlating the result of the Hazard Identification with workers exposure models. The latter should be defined with the best possible detail, taking into account, however, that the diversification of tasks is often quite blurred in spite of the formal job descriptions (in a real case of use of TBM we found 11 official job descriptions, but identified only 3 typologies of actual job) 3. Risk Assessment: The results of the Risk Analysis are here used for decision making, through direct comparison with minimized risk targets (e.g., Occupational Exposure Limits (OELs) values if available (Skowroń, 2013), or relative ranking of effectiveness and cost of different risk reduction measures based on different techniques and technologies 4. Risk Management: Selection of both the most appropriate technologies and techniques for winning, mucking, ventilation, etc. and the management policies, procedures and practices, to grant along the time Occupational Safety and Health, neighboring areas environmental quality and economic effectiveness ...
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