Avaliação de risco da explotação e beneficiamento de quartzito em Várzea - PB

Abstract

The present study seeks to identify and analyze the hazards in exploitation of ornamental stones. To reach the proposed objective, we conducted an investigation in the productive system (exploitation, beneficiation and marketing) in region of the Várzea city (PB), one of the main poles extractors and processors of quartzite of the state of Paraíba, Northeastern Brazil. The exploitation of quartzite is performed by several miners for more than 40 years and involves more than 900 workers, it’s the main source of employment and income of the city. The study allowed to describe the productive system (exploitation, beneficiation and marketing), subdividing it into stages, identify and analyze only on the exploitation, the main hazards involved in each of its stages. Thus opted for a search of hybrid character (quantitative and qualitative) with the application of two risk assessment techniques: FMEA (analysis mode and effect of failures) and the FTA (fault tree analysis). The FMEA generated as results the definition of the risks of exploitation, its classification as to the importance, as also identified its causes, consequences and proposed measures that should be adopted to mitigate them. The FTA was used to allow a clear view through a graphical representation of the possible causes of these risks, becoming a facilitator in managing the risks in mining activity. The weighting of the risks showed that dust containing high percentage of crystalline silica (44.3% -70.7% SiO2), the noise, the use of explosives, vibration, and the informality of mining activity were the risks that had the highest percentages, both for individual assessment of risks as for the characterization of the steps from exploitation. Finally, the fault trees were built, where possible qualitatively describe the main causes of fatal accidents involving workers. Since at this stage they were used dimensions suggested by completing the FMEA form and the literature review. The results obtained during the study are characterized as essential to draw up proposals, goals and strategies to manage the risks evaluated by the above methods.