ABSTRACT
This chapter describes some accidents which were the result of maintenance errors. Sometimes the maintenance workers were inadequately trained, sometimes they took short cuts, sometimes they made a slip or had a moment's lapse of attention. Sometimes it is difficult to distinguish between these causes, or more than one was at work. As with construction errors, it is often difficult or impossible to avoid them by a change in design and we are mainly dependent on training and inspection. However, designs which can be assembled incorrectly should be avoided, as should equipment such as bellows, which are intolerant of poor quality maintenance. Technically it is certainly feasible. In the nuclear industry, where maintenance is difficult or impossible, equipment is designed to operate without attention for long periods or even throughout its life. In the oil and chemical industries it is usually considered that the high reliability necessary is too expensive.
