PAWSA provides an assessment of risk in a defined waterway by means of a structured two‐day workshop. It is undertaken by carrying out a subjective assessment of the probable risk in that waterway based on the experience of teams of maritime experts and other stakeholders under the supervision of a Facilitator.
The theoretical concept underlying the PAWSA process is the proven systematic decision making ‘Delphi’ method of converting the opinions of experts with local knowledge into quantified results. The experts complete a series of tasks set out in MS Excel™‐based Workbooks. After each stage, the Facilitator provides a summary of the experts’ decisions from the previous stage as well as the reasons for these decisions. The experts are therefore encouraged to revise their earlier answers based on the replies of other members of their team. This will ideally reduce the range of the answers so the team will converge towards the ‘correct’ answer. The ‘Delphi’ method used in PAWSA is based on the principle that decisions from a structured group of individuals are more accurate than those from unstructured groups.