When the Human Factor is at the Core of the Safety Barrier

There are situation in the industry where the human actions are the main safety barriers to abnormal or accidental conditions. In order to maximize the reliability of good human and organizational barriers we need to ensure that the action-plans generated are based on a valid risk assessment of the situation to be addressed and informed by a relevant human factor analysis. This implies that the process needs to be participatory in nature, thus involving end user all the way through. In this paper we present a study in which a critical scenario of vessel overpressure was analyzed using a bowtie. The Bowtie was based on the information provided by a company that supplies industrial gases and services to various industries. The case study is the human and organizational factors that may cause truck drivers to overfill storage tanks on customer premises; the goal is to list proposals for improvement. It became clear that the only safety barrier currently available to avoid the risk of overfilling and possible consequent vessel overpressure is represented by the driver performance on the task. For the example proposed we involved the end user in reviewing the risk assessment and in suggesting possible improvements. The one to be selected were rated on the basis of their impact (in terms of risk reduction) and the difficulty/cost of implementation, The benefit of the approach impacts not only on the quality of the background information provided for the risk assessment but more importantly the involvement of the main end users of the system in assessing their own work performance and being proactively called to identify way of improving the reliability and safety of i