335 Safety, Reliability and Risk Analysis: Beyond the Horizon – Steenbergen et al. (Eds) © 2014 Taylor & Francis Group, London, ISBN 978-1-138-00123-7 Modeling contractor and company employee behavior in high hazard operation Pei-Hui Lin, Daniela Hanea, Ben J.M. Ale Safety Science, Technical University Delft, Delft, The Netherlands ABSTRACT: The recent blow-out and subsequent environmental disaster in the Gulf of Mexico have highlighted a number of serious problems in scientific thinking about safety. Risk models have generally concentrated on technical failures, which are easier to model and for which there are more concrete data. However, many primary cause of the disasters, such as BP’s Texas City and Deepwater Horizon, are rooted in management decisions and organizational. Therefore, there is a strong need to develop a risk management support tool for chemical process industries which incorporates human and organizational factors into quantified risk models. In this paper, we model two human performance model for oil and gas company Royal Dutch Shell. Interviews were conducted to obtain important human factors. As the quality and operation of the management actions have important influences on human factors (e.g. safety attitude, training), we have linked a safety management model with the human factors model and quantify the risk implications of different management changes to prevent accidents. The methodology of integrat- ing organisational factors into a Bayesian Belief Networks (BBNs) model is discussed in Lin et al. (2012). In this paper the development and quantification of human and management factors for an international oil company is given. own personnel and the personnel hired through contractors are built. The structure of the human models and their development are described in more detail in section 3. The influences of manage- ment on human model are shown in section 4. This section also discusses the influence of management which follows with the conclusions. 2 LINKING HUMAN FACTORS IN SAFETY BARRIERS IN THE CAUSAL PATHWAY Figure 1 shows a BBN for a vessel or vessel-like equipment. All the barriers indicated have the pur- pose of preventing a loss of containment. Barrier failures occur when at least one out of three generic barrier functions are broken. These functions are 1 INTRODUCTION It is now widely acknowledged that human failure and organizational factors are the fundamental causes of many major accidents and incidents, e.g. Texas City, Piper Alpha, Chernobyl. However, introducing human factors and organizational fac- tors into risk models is a big challenge in the cur- rent worldwide research, mainly due to poor data availability and the difficulty of capturing soft variables in an appropriate and quantifiable way (Lin, 2011). To make the human factors amena- ble for quantification, the human factors have to be translated into proxy quantities. How to model the human factors and the management factors by the proxy variables without losing their actual influences is one of the main challenges in risk modelling for human factors. The objective of this paper is to incorporate human factors into the risk assessment model of oil and gas operations within the technical risk model for Royal Dutch Shell. In this paper we illustrate the quantification steps and the questions designed for reducing the current quantification limitations for human factors in oil industry. Section 2 provides a brief overview of the quantification method for human factors. Human models for two types of people: the companies Figure 1. One layer protection system.