Both international functional safety standards, IEC 61508 and ISA84.01-2004 (IEC 61511 MOD.) have clauses describing Prior Use requirements. One should also refer to TR84.00.04 for additional information on Prior Use.
This paper will discuss some of the particular roadblocks found at the plant site in trying to meet Prior Use guidelines in the ISA84.01-2004 (IEC 61511 MOD.) standard. This paper will not discuss the process for assessing the equipment.