TRAGEDIES like the 1987 fire at Kingās Cross station on the London underground could be prevented if engineers thought more carefully about the language they used in safety documents, says a computing specialist. And the way to do this, he says, might be to borrow one of the techniques of literary criticism.
At the inquiry into the Kingās Cross disaster, which killed 31 people, managers were criticised for using the word āsmoulderingsā to refer to small, rubbish-fuelled fires like the one that led to the disaster. This is no isolated case, says Jim Armstrong, a computer scientist specialising in software reliability at the University of Newcastle upon Tyne: āItās a good example of a euphemism used to pass safety problems off as perfectly natural and ordinary ā not something to worry about.ā
Armstrong thinks that the theories of Jacques Derrida, the French philosopher behind the branch of literary criticism called deconstruction, could help uncover ambiguity, bias and self-deception in the safety systems of installations such as nuclear power stations and chemical plants.
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A major aim of the project is to find ambiguous terminology that regularly crops up and bring it out into the open. But the very nature of deconstruction means that a formal system for applying it to safety is unlikely to be developed. āIt cannot settle an argument, only āunsettleā it,ā Armstrong says.
However, he hopes his work will lead to a new discipline of āsafety philosophyā, in which the way people think about safety is properly discussed. He thinks the ārelentlessly scepticalā approach characteristic of deconstruction could help combat the kind of complacency that led to the Kingās Cross fire, or the Chernobyl disaster.
Though Armstrongās ideas have, unsurprisingly, had a mixed reception, some safety experts think the approach could be useful. āItās an unusual, even oddball approach, but itās certainly worth looking into,ā says Martyn Thomas, an expert in safety-critical software and chairman of a dependable systems research group in Britain.
Definitions of deconstruction theory often run to several pages, but one of the central ideas is that meaning should never go unquestioned. The authorās words are pulled apart to reveal all other possible meanings, to see if there are any unconscious assumptions at work that may skew things dangerously. āHe really looks into the limits that language imposes on thought,ā Armstrong says.
One concept that is viewed pretty much as holy writ among safety engineers, for example, is that the risks in any system should be reduced to a level that is āas low as reasonably practicableā, known as ALARP for short. But, applying Derridaās ideas, āreasonablyā simply means āin accordance with someone elseās preconceptionsā, says Armstrong.
And āpracticableā boils down to what youāre willing to pay for. It hides the fact that spending more money, for instance, might mean a safer system. āOne of the Derridian insights Iāve had in this project is that to modify a word by putting an āableā on the end of it makes it look specialist and technological, providing an unwarranted degree of comfort,ā he says.
Armstrong is in the middle of a two-year project, funded by Britainās Engineering and Physical Sciences Research Council, to demonstrate that this sort of approach could help improve safety. He is looking at case studies where things have gone wrong, and hopes to show that deconstruction analyses could have helped prevent them. For legal reasons, he was reluctant to discuss the details of specific cases with Āé¶¹“«Ć½.
So what has language got to do with the safety of nuclear plants? Anyone designing a safety-critical system to control such a plant has to supply a written āsafety caseā explaining its operation to the relevant regulator, such as Britainās Nuclear Installations Inspectorate . This document details circumstances in which the system will operate safely, when it will fail safely, and under what conditions it might risk catastrophe. āSafety cases are hard to prove correct,ā Thomas says.
And according to Armstrong, the so-called ādependability argumentsā that make up a safety case are utterly subjective ā informed by politics, economics, the writerās expertise and potentially limited data on the system itself ā and can contain dangerous linguistic anomalies. For instance, if an engineer states that a nuclear waste tank is safe as long as the level of the noxious liquor it contains never exceeds a certain level for more than an hour, what do they actually mean by āthe levelā? Do they mean the median level? The mean? The root mean square? Or maybe the minimum level? Such ambiguity could kill.
But the safety cases for nuclear plants are āvery, very, very technical documentsā, says an inspector from the Nuclear Installations Inspectorate, who did not wish to be named. He defies any expert in literary criticism to analyse them: āYouād need the right background in nuclear engineering to do it.ā