[en] This report presents the results of the second phase of a two-phase project undertaken to develop a more detailed understanding of the manner in which control room crews perform assigned tasks when mitigating plant malfunctions. Phase II had these objectives: (1) apply the task analysis (TA) methodology developed in Phase I for assessing pressurized water reactor (PWR) crews to create a data base for boiling water reactor (BWR) crews; (2) show how objective data collected during high-fidelity simulation runs can be used to augment TA data collected concurrently; (3) examine additional objective measures of operator performance; and (4) begin to apply the TA data to the development of predictive models of operator/system performance. Ten plant malfunctions were presented to two-man crews on a Boiling Water Reactor training simulator. Videotaped records of all simulation runs, written operating procedures, interviews, and talk-throughs were data sources for the entry of task analysis information into a computer-searchable data base