Operational Safeguards Arrangements (OSAs): The Use of Safety Case Methodology and its Application to Safeguards

In order to safeguard large bulk handling facilities the safeguards approach inevitably involves the deployment of a significant array of safeguards equipment (both inspector owned and branched from operator systems). Additionally, the operator will embed safeguards activities into the plant operating regime, effectively influencing the way the plant is operated. This paper presents a methodology that is being investigated to increase the level of assurance to the operator that the safeguards arrangements or equipment in a plant or process area are not adversely affected as a result of modifications or changes to plant processes, equipment or operating regimes. This approach is based upon the development of “safeguards cases” by utilising some of the processes and techniques associated with the development of safety cases and applying them to safeguards. To avoid confusion these will be referred to as Operational Safeguards Arrangements (OSAs). Safety case process owners have been approached to support the development of OSAs and identify synergies from their safety case experience. The early results from a pilot study are presented which recommends how best to develop and implement the OSA process into plant procedures and practise.