This paper describes and uses the format required for submitting to ErgoIA 2006. The accepted submissions will be published in the ErgoIA 2006 proceedings This paper aims to introduce a barrier modelling technique to use through the design processes of industrial systems. In this model, the barriers are classified according to their effects on the elementary risk analysis entities. Risk indexes are calculated to allow the designer to evaluate the alternative design configurations. An importance index is introduced to evaluate the marginal effects of the barriers on the total risk index. Based on this model, a barrier analysis workbench is embedded in an industrial design application. This model provides a platform to share the risk analysis information with the other design system modules, which increases the facility and effectiveness of the risk prevention.