a dempster-shafer evidence theory for environmental risk assessment in failure modes and effects analysis of oil and gas exploitation plant

The oil, gas, and petrochemical industries, as one of the largest sources of environmental pollutants, have different types and levels of pollution depending on the type of input materials, process steps, and output products. various stages of exploration, extraction and processing of oil and gas have many environmental effects, such as those on soil, air, water, creatures, plants, and even humans. in this paper, a failure mode and effects analysis (fmea) is employed to identify failures and environmental risks in an oil and gas exploitation plant. dempster–shafer (ds) theory of evidence is then proposed for environmental risk assessment due to its effectiveness in dealing with uncertain and subjective information. the assesments of experts and their confidence levels of their responses are employed to construct the basic probability assignments (bpa) in ds theory of evidence. furthermore, a new weighting method is proposed to obtain the discounted bpa which reduces the uncertainty in the information sources and improves the quality of information before combining different sources of information. finally, the proposed method is applied to an oil and gas exploitation plant to assess environmental risks.