Control systems, redundant, chemical plant design

Computer-controlled chemical plants are becoming the rule rather than the exception. As a result, it is possible to measure more variables and get more process information than ever, and chemical plants can be made inherently safer than ever before. However, it must be kept in mind that instruments and control components will fail. It is not a question of if they will fail, but when they will fail, and what the consequences will be. Therefore, the question of redundancy must be thoroughly considered. The system must be designed so that when failure occurs the plant is still safe. 

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