Root Cause Determination

DOE-STD-1045-93

and factors affecting human performance are compared. An evaluation to

identify any detrimental effects on plant equipment should be included.

The event should be compared with previous investigations of similar

events or transients. If the event was a reactor trip, the acceptability of

restart is determined.

Root Cause Determination

The root causes of the event should be determined whenever possible.

Root causes are those fundamental causes that would have prevented the

event from occurring and, if corrected, prevent recurrence. Typically

correctable without additional research or analysis, root causes explain

why direct causes existed.

Corrective Action Determination

Each event investigation results in corrective action being established, and

specific personnel are assigned responsibilities for such action. Corrective

action can be procedure changes, training, design modifications, and

administrative controls changes; and may include better supervisory

involvement and oversight of work activities and increased worker

accountability. Interim compensatory actions may be used while longer-

term corrective actions are being developed. Cognizant managers should

agree to each corrective action before it is performed, and the facility

manager approves it.

4.2.4

Investigative Report

An essential part of the investigation is informing others, so recurrence of the

event can be prevented. A report of the investigation, including discussion and

explanation of the results of the analysis and identification of the corrective

actions, should be prepared in accordance with facility guidelines. The

investigation report should be reviewed by appropriate managers, supervisors,

and the safety review committee to ensure that lessons learned from the event

are identified and incorporated into applicable facility programs as discussed in

section 4.2.5. The final report should be reviewed and approved by the facility

manager.

Those occurrences requiring formal notification, in accordance with DOE

Order 232.1A, also require a formal occurrence report. Instructions for