Intervention techniques, safety performance

Fault tolerance in field instmmentation is mainly concerned with redundancies that in case of a basic plant control system (BPCS) ensure continuance of operation. In the case of a safety instmmentation system (SIS), they additionally minimize nuisance or spurious interventions and alarms. Redundancy in BPCS also improves safety. With properly selected and installed transmitters, improved performance can be achieved by measuring the same variable with more than a single field device. When field devices are more than 2, voting circuits are necessary. In this way m measurements out of a total of n number of signals are made so that m > n/2, for example, m = 2, n = 3, 2oo3 is the selection by voting. There are standardization of redundancy and voting techniques. Some of these are presented next. These are applied for both BPCS and SIS. 

The results of this preliminary investigation accorded with historical perspectives and recent sport coaching interventions of the critical nature and immediacy of mental state changes on performance. The person focused approach must be seen to be timely given the magnitude and frequency of human error attributed to incidents. The economy and utility of an intervention that operates in a one-to-many relationship such as the recoveiy of SA process (one technique that addresses many types of situations), is an attractive prospect to that of the present many-to-many (a specific procedure to deal with each situation) approach in safety training. 

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