Cleveland TS23 4YS. Guiding principles for the proof testing of safety instrumented systems (SIS) in the chemical industry. have been developed through research into the practices of proof testing. The proof testing of SIS is an. integral component of the management of functional safety. Its purpose is to confirm the continued.
Psychology of obsession. The definition of obsession is: the inability of a person to stop thinking about a particular topic or feeling a certain emotion without a high amount of anxiety. When obsessed, an individual continues the obsession in order to avoid the consequent anxiety.
Common obsessions include: 1  Fear of dirt or contamination by germs. 2  Fear of causing harm to another. 3  Fear of making a mistake.  Fear of being embarrassed or behaving in a socially unacceptable 1  manner. Fear of thinking evil or sinful thoughts.  Need for order, symmetry, or 1  exactness. Excessive doubt and the need for constant reassurance.