A process for measuring the usability of plant procedures

In a survey of 21 nuclear power plants, maintenance managers identified 19 major categories of procedure-related problems that cost an average plant up to ε annually in lost power generation and equipment. The seriousness and extent of procedure problems was further substantiated by an NRC study which found procedures to be a contributing factor in more than 65% of the 1995 Licensee Event Reports. Forty percent of LERs involved inadequate procedures, with another 26% due to workers not following the procedure. A US Department of Education-sponsored survey of industry revealed that literacy related problems are costly, leading to serious errors on the job. The complexity, level of detail, and amount of information contained in many plant procedures is at odds with the prevailing functional literacy in the general population, despite high nominal education and reading levels. Presently, a method to measure the effective use of procedures is not available, making it difficult to evaluate procedure usability. This paper describes the results of an EPRI-sponsored project whose objective was to develop a systematic process for measuring how well plant workers can use task-based procedures. The Procedure Usability Measurement Process (PUMP) was designed to generate empirical data on procedure usability that could quantify procedure problems, diagnose specific procedure weaknesses, and guide remedial actions in the areas of procedure-writing and training. The PUMP process was pilot tested at Zion Station (Zion, IL) during 1996