Rating: 
Summary: Cool water for hot-headed analysts of complex systems
Review: I'm dismayed to discover that 'Normal Accidents' is so difficult to find. Like all voters, I'm sometimes asked to make choices about the use of potentially devastating technology, despite having no training in engineering and only a sketchy idea of statistical risk analysis. 'Normal Accidents' doesn't reduce my reliance on experts, but it does provide a common language for us to discuss the issues. Perrow's accident descriptions are masterly, and should disturb anyone who lightly dismisses accidents in complex systems as "simple human error", or assumes that all systems can be made safe by a technological fix. I've used Perrow's complexity / coupling matrix as a tool for thinking about and discussing the risks involved in decisions about many systems in addition to those Perrow actually discusses, not least software systems. I think this book still has a lot to offer anyone interested in public debate about complex technological issues, and I hope it will be reprinted. A new edition would be even better.
Rating: 
Summary: Where are all the catastrophes he talks about?
Review: It's a good and interesting theory motivated by a desire to do away with nuclear power. Fine and dandy, but the problem is that while we can tick off a few major disasters: Chernobyl, Bhopal, possibly the intelligence failure leading up to September 11th, the truth is, all his doomsday prophecies have yet to come true. Maybe Perrow is a Cassandra, unlistened to and unappreciated until his prophecies come true. There are a variety of managers who have taken up the task of managing their complex, tightly coupled systems for reliability. Perrow addresses some of them in the afterword to the 2000 edition, but he gives them short shrift. No doubt Perrow touched off a flurry of new research on organizations and this book has, thus, become a classic. But some classics have to be update4d, rethought, and evaluated once again with the searching spotlight of new knowledge. The fact is, at a major weapons lab in the southwest there will be on the order of 1000 fatalities in 1000 years from traffic accidents and only 5 in 1000 years from nuclear related disaster. While traffic movement is complex and tightly coupled, it is probably not a system as he defines it. My suggestion is to read Perrow with Sagan, grasp the underlying theory behind Normal Accident Theory and then read the work of the Berkeley High Reliability Organizations group (Rochlin, LaPorte, Roberts, Weick--at Michigan) etc. THis will give a more well-rounded picture.
Rating:
Summary: Where are all the catastrophes he talks about?
Review: It's a good and interesting theory motivated by a desire to do away with nuclear power. Fine and dandy, but the problem is that while we can tick off a few major disasters: Chernobyl, Bhopal, possibly the intelligence failure leading up to September 11th, the truth is, all his doomsday prophecies have yet to come true. Maybe Perrow is a Cassandra, unlistened to and unappreciated until his prophecies come true. There are a variety of managers who have taken up the task of managing their complex, tightly coupled systems for reliability. Perrow addresses some of them in the afterword to the 2000 edition, but he gives them short shrift. No doubt Perrow touched off a flurry of new research on organizations and this book has, thus, become a classic. But some classics have to be update4d, rethought, and evaluated once again with the searching spotlight of new knowledge. The fact is, at a major weapons lab in the southwest there will be on the order of 1000 fatalities in 1000 years from traffic accidents and only 5 in 1000 years from nuclear related disaster. While traffic movement is complex and tightly coupled, it is probably not a system as he defines it. My suggestion is to read Perrow with Sagan, grasp the underlying theory behind Normal Accident Theory and then read the work of the Berkeley High Reliability Organizations group (Rochlin, LaPorte, Roberts, Weick--at Michigan) etc. THis will give a more well-rounded picture.
Rating: 
Summary: Insightful perspective on serious industrial accidents.
Review: Normal Accidents is the best summary of major industrial accidents in the USA that I have encountered. It is written in a factual and technically complete style that is particularly attractive to anyone with a technical background or interest. I was able to read a borrowed copy from a colleague a few years ago when I was appointed as chairman of the safety committee at a manufacturing facility where workers had potential for exposure to toxic gasses, high voltage, x-radiation, and other more everyday industrial hazards. The author's insight is right on target for achieving a workable understanding of the cause and prevention of disaster events. I wanted to buy copies for all our engineering managers and safety committee members, but the book is out of print. It is my fond hope that the author will write an updated version with analysis of more recent events as well as the well-chosen accidents in the previous edition. For any safety related product or process de! ! signer, this book is a must read! For any technically cognizant reader, this book is a delight to read, even if it is a little scary in its implications. For everyone else, it has some really interesting historical stories.
Rating:
Summary: Outstanding
Review: Perrow is one of these few authors whose name in a cover means that you are going to find something interesting inside. However, he does not manage buzzwords of the systemic field, his point of view is fully systemic. This book, where he explains why accidents happen from the point of view of organizational complexity is interesting not only for people devoted to safety but for any people interested about organizations. A final clue: Many people can be asking themselves if Quality, ISO9000 and so on is going to be enough to guarantee the success. The answer can be found in this book and, more important: You can find too why not.
Rating: 
Summary: Good Sociologists Should Not Dabble in Engineering
Review: Perrow regurgitated too many facts. Give us enlightenment. Give us a view of system safety we have not seen before. Give us substantial information by which we can make decisions. Present us with critical analysis about what engineering and operational safety processes work and what do not work. Don't regurgitate history to us. We can get it elsewhere. It is a good summary for historians on accidents, but its not good for those in positions who can make systems safer. If you want to know about accident prevention go to the System Safety Society.
Rating:
Summary: Good Sociologists Should Not Dabble in Engineering
Review: Perrow regurgitated too many facts. Give us enlightenment. Give us a view of system safety we have not seen before. Give us substantial information by which we can make decisions. Present us with critical analysis about what engineering and operational safety processes work and what do not work. Don't regurgitate history to us. We can get it elsewhere. It is a good summary for historians on accidents, but its not good for those in positions who can make systems safer. If you want to know about accident prevention go to the System Safety Society.
Rating:
Summary: This book will be reprinted in 1999
Review: Prof. Perrow indicates that a reprint with an epilogue (including comments on Y2K) should be published in 1999 by Princeton University Press.
Rating:
Summary: Engineering Nightmares Discussed
Review: There are plenty of books that discuss the engineer disasters that make our headlines. Perrow, however, looks deeper into the source of the problem and attempts something that few authors dare try--find a solution. This is definitely not leisure reading and is poorly edited. However, the subject matter is excellent. If you are studying the topic of technologial failure, read this book.
Rating:
Summary: Not the last word, but provocative and well argued
Review: This book's impact, for me, consists of the insight that people are part of the systems they build and operate. Because "to err is human", everyone from designers to operators makes mistakes from time to time. In complex systems, such mistakes can be expected to result in a steady stream of component failures, malfunctions, and accidents - hence the book's provocative and memorable title.
After a very readable introduction, the author examines six important areas of technology (nuclear power, petrochemical plants, aircraft and airways, marine accidents, dams and mines, and "exotics" - space exploration, weapons of mass destruction, and recombinant DNA research). He plots these on two dimensions - complexity and coupling - and comes to the unsurprising conclusion that complex, tightly-coupled systems are bad news. Complexity means that unexpected accidents will happen, and tight coupling means that when they do happen, they will touch off further problems too quickly for human intervention.
First published in 1984, the book shows its age in some ways, and the author has updated it somewhat with an Afterword and a Postscript on the Y2K problem.
It would be hard to read even the first chapter without feeling dismay at the apparent gaping weakneses of the systems described. It looks as if the greatest source of trouble in nuclear power systems, for example, is the routine failure of valves controlling the flow of water through pipes! True, the water may be at hundreds of degrees Centigrade, loaded with chemical contaminants, and even radioactive - but surely this is 19th century (or, at worst, early 20th century) technology?
Then there is the ubiquitous evidence of human inadequacy. Imagine trying to monitor the working of a nuclear power plant whose control panel has 1600 separate switches and lights! (Especially when some of these have failed, and those awaiting repair are marked out by ordinary labels that hang down in fron of other, essential warning lights, preventing them from being seen). According to Perrow, one type of highly critical valve used to prevent a reactor melt-down was rated by its own manufacturer as likely to fail at least once every ten times it was activated! And it is hard to get excited when a fault light comes on, if it is known to have a habit of "playing up".
It is the people failures, though, that are most disturbing. One of the most vital parts of a nuclear power station is the concrete containment structure, which makes sure that whatever accidents may occur, the external environment is not affected. So it is scary to hear about construction crews who did not seem very good at pouring concrete, to the extent that holes up to 180 cubic feet in size were found inside the walls they had built!
Perrow relates many other interesting stories, perhaps the best being the one about the oil company that was drilling through a lake bed in the vicinity of a huge salt mine... resulting in the disappearance of lake, salt mine, oil rig, several boats, and part of a hotel. All because it was no one's particular job to make quite sure that the drill missed the mine...
It seems clear that, as Perrow suggests, people should be assessed and evaluated as a system component. Just as steel or concrete comes in various grades at corresponding prices, people tend to have a characteristic "defect level" which is not altogether uninfluenced by their cost. When companies, perhaps because of hard times, skimp or ignore maintenance, cut out training, and fire the most experienced (and highest paid) workers, accidents are likely to become more frequent.
In fact, we would have far more catastrophes but for a fact that Perrow also emphasizes - it is quite hard to cause a disaster. Everything has to be just right. In some industries, such as marine transport, this means that owners can continue to get by with minimum levels of investment. Sometimes, they are entirely insulated from the consequences of accidents.
I feel that the book has opened my eyes in a number of ways, but I still suspend judgement. For one thing, Charles Perrow is a professor of sociology, not an expert in engineering or systems theory. Nothing wrong with that - it gives him a usefully "skewed" point of view - but he is probably not entirely qualified to understand engineering systems. Moreover, I feel he is at his best when relating case studies and drawing specific conclusions with his sociologist's hat on. His attempts to start a new discipline called "Normal Accident Theory" (NAT) do not look very convincing to me.
Nevertheless, this is a fascinating book filled with interesting (and sometimes frightening) facts and interpretations. I feel sure that its core message - that human beings are part of the system, and should not be challenged beyond their reasonable limits - will be learned and taken into account by enlightened system designers.
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