INRAT-H study guide
INRAT-H · Work through your exam, one topic at a time.
INRAT-H, also described as the Human Factors paper within the International Nuclear Reactor Operator License Examination family, is a professional knowledge assessment focused on how people actually perform inside a nuclear control room. It is aimed at licensed operators, senior reactor operators, shift supervisors, simulator instructors, human factors practitioners, and regulator or utility staff who review operating events and crew performance. The INRAT-H study guide has 8 sections and about 2,251 words.
01Human Performance Fundamentals and Error Mechanisms
Human performance in a control room is best understood as the product of capability, context, and constraint. Candidates must distinguish skill-based, rule-based, and knowledge-based performance (Rasmussen) and match error types to them: slips and lapses dominate skill-based work, rule-based work produces misapplied or wrong rules, and knowledge-based work yields biases and faulty mental models.
361 words, about 2 min02Cognitive Processes: Attention, Perception, Memory, and Decision Making
Operators work within bounded cognition. Understand selective and divided attention , vigilance decrement (performance falls in prolonged low-event monitoring), inattentional blindness and change blindness (failures to notice unexpected or altered indications), and expectancy effects (seeing what is expected).
316 words, about 2 min03Human-System Interface and Control Room Design
Interface design should fit human perception and action. Know affordances and mapping (controls arranged to match process layout), compatibility (movement and display direction consistent with expectation), population stereotypes , and stimulus-response compatibility .
290 words, about 1 min04Procedures, Human Factors Engineering, and Task Analysis
Procedures translate intent into reliable action. Know the difference between normal, abnormal, emergency, and surveillance procedures, and the value of action steps versus check-off steps and place-keeping .
293 words, about 1 min05Fatigue, Stress, Workload, and Shift Work
Fatigue degrades vigilance, reaction time, and judgement, and increases variability. Know circadian rhythm effects, the post-lunch dip , and the circadian low in early morning hours, when error risk peaks.
281 words, about 1 min06Teamwork, Communication, and Crew Resource Management
Crew resource management (CRM) covers communication, leadership, followership, and coordination. Know closed-loop communication (sender, receiver readback, confirmation), standard phraseology , and the hazards of ambiguous or implied communication .
228 words, about 1 min07Safety Culture, Human Reliability, and Event Investigation
Safety culture includes reporting, just, flexible, learning, and informed cultures. Distinguish person-centred (blame) from system-centred views; a just culture separates honest error from reckless behaviour.
247 words, about 1 min08Training, Competence, and Licensing of Control Room Personnel
Competence combines knowledge, skills, and behaviours. Know initial training , refresher training , on-the-job training , and simulator-based training .
235 words, about 1 min