Understanding the interaction between public policy, managerial decision-making and the engineering of critical infrastructures

Failures in national and international infrastructures have causes that stretch well beyond the specific events that trigger an accident or incident. The following pages argue that these latent causes can be traced back through the decisions of local management teams to higher-levels of public policy. For example, the 2003 blackout of areas in Canada and the USA was triggered by ‘flash overs’ that occurred when distribution lines sagged too close to the surrounding vegetation. The causes of this failure can also be traced back to longer term problems in regulating competitive and reliable energy markets. Traders could market electricity without supporting the transmission infrastructure, for example by meeting the costs of vegetation management across thousands of miles of power lines. Similarly the Linate runway incursion was caused when Air Traffic Control Officers (ATCOs) failed to detect that a Cessna had strayed from its authorized taxiways. However, these ‘mistakes’ were strongly influenced by their technical infrastructure. The lack of effective Ground Movement Radar systems can, in part, be traced back to managerial and regulatory decisions. These, in turn, were influenced by public policy including the joint responsibility for Air Traffic infrastructures within the the Ministero delle Infrastutture e dei Transporti and the Ministero dell’Economia e delle Finanze. Public policy, therefore, creates the context in which infrastructure failures are likely to occur. It is, however, very difficult for engineers to predict the many different ways in which higher level decisions will influence the long-term reliability of critical infrastructures. The following pages, therefore, use an accident investigation technique to provide a detailed graphical overview of the interaction between public policy, local managerial decision making and operator actions. The intention is to alert engineers to the importance of public policy in creating the context in which their systems will be used. We also aim to show politicians and regulators the consequence that their decisions have upon the engineering of safety-critical systems. This paper was motivated by observations of a recent workshop on Safeguarding National Infrastructures held in Glasgow, Scotland. It builds on the analysis presented by the other papers in a special edition of Elsevier’s Reliability Engineering and Systems Safety journal. These other papers are indicated by references that are not accompanied by a numeric index.