Dynamic occupationalrisk model for of fshore operations in harsh environments

摘要

Offshoreoperations pose severe occupational hazards.Now as operations are expanding to remote and cold areas (i.e., Arctic), the occupational hazards are worsened due to harsh environments.This demands more attentions on occupational risk assessment and minimization.The risk profile is essential to determine effective prevention measures; risk assessment is an indispensable part of occupational accident prevention.However, the traditional assessment methods (e.g., QRA) cannot capture the change of risks with time and environments.This paper proposes a methodology to dynamically assess and manage the occupational risks on offshore rigs in harsh environments.The detailed steps are listed as follows: i) identifying the influential and frequent occupational accidents for offshore oil in harsh environments.ii) Analyzing the logic relations between risky factors, safety barriers and consequences for each selected occupational accident.In this step, Bow-tie Model is applied to represent the relations more clearly.iii) Establishing the dynamic risk model of occupational accidents for offshore operations.Bayesian Network Model is excellent to model dynamic process.With BN Model, the probabilities of given occupational accidents and consequences are calculated with prior information of risky factors and safety barriers.iv) Updating the risk profile.New observed data about selected accidents are collected and put into BN Model.Using the dynamic property of BN Model, probabilities of occupational accidents and severity are updated.v) Proposing occupational risk management measures.Depending on the latest risk profile, effective measures are proposed to prevent occupational accidents.An application of the proposed methodology will also be discussed in the paper.