Training methodology for Chashma3 August 2002
The Pakistan Nuclear Regulatory Authority (PNRA) has awarded 12 shift supervisor and 30 shift engineer licenses to Chashma plant operating staff to date. By Amer Manzoor, Mahmood Shah, and Zahid Salman
CHASNUPP Centre of Nuclear Training (ChasCeNT) is the on-site training department of the Chashma nuclear power plant, a two-loop 325MWe PWR in Pakistan.
In order to maintain the expected high standards of plant operation that are required, ChasCeNT is responsible for ensuring the competence of the operating personnel by conducting comprehensive examination programmes and to ensure that the licensee candidates have kept up the required knowledge and skill level.
The centre has been fully equipped with plant-specific full-scope training simulator, engineering laboratories, physical models house, library, auditorium and classrooms. It provides in-class and simulator-based routine training to the operators pertaining to all areas of the plant, and in addition to this, it provides the non-plant-specific training about subjects such as scientific fundamentals, radiation protection and industrial safety.
The training programme has two parts: new operators training and re-training.
New operators training
This training programme is spread over a period of 43 working days each of them consisting of 8 working hours. Each day has 4 hours of classroom lectures followed by 4 hours of simulator session.
The lecture series includes the full spectrum of plant systems describing the basic system design, technical specifications, detailed system description, applied instrumentation, control and interlocks, and general/abnormal/ emergency operating procedures of the system.
The simulator training is a hands-on experience session to impart a matching level of plant operating skill to the trainees. The training follows the following format:
Day 1 - Familiarisation
This consists of the introduction to new entrants, introduction to ChasCeNT, the distribution of the course plan and training material, the formation of groups and panel walkthrough.
Day 2-16 - Training in general operating procedures
In-class training contains a detailed study of the procedures to operate the plant under different conditions - plant warm-up and cool down, start-up and shutdown, boron concentration control, reactor criticality and nuclear power control, turbine roll up/down, steam line warm-up, connection/disconnection of the main generator with the grid and power range operations.
The simulator training is to perform the operating procedures practically, taking different systems into and out of service and observing plant responses.
Day 17-31 - Training of abnormal operating procedures
The class session includes study of plant procedures related to malfunction/failure of particular instruments, equipment, channels, control systems and different process systems at nuclear and conventional islands.
The procedural acquaintance of the trainees with abnormal conditions inclusive of coolant leakage, turbine trip, reactor trip, and electrical equipment at various conditions of the plant is given.
After the trainees have gained a complete and full understanding of the possible malfunctions and plant responses, the simulator training sessions begin to cover the full operational envelope of the pre-studied transients.
Day 32-37 - Training of emergency operating procedures
Study and practice of the recommended procedures to cope with the plant under accident situations like loss of coolant accident, safety injection, main steam/feed water line breaks, steam generator tube rupture and station blackout.
Day 38-43 - Revision and examination
One day of the course is reserved for the review and discussion of the exercises done during the course, followed by a detailed examination to look closely at the trainee's knowledge and proficiency.
Examination and grading
The examination carries a total of 200 marks. In order to compile an accurate assessment profile of the candidates, two types of test are performed: written and simulator-based.
This examination of 6 hours duration carries 100 marks from the following six major areas:
• Reactor operation physics.
• Design basis of plant systems and equipment.
• Systems operating characteristics.
• Instrumentation and control.
• Safety and emergency control systems.
• Operating procedures.
The assessment of the candidates is conducted in two separate parts - individual evaluation and team/ group evaluation.
The individual examination carries 25 marks for the simulator exercise and 25 marks for an oral examination.
The criteria for the evaluation of individuals, based on one-hour duration at each operating position in the control room during the simulator test, is compliance and correct usage of the procedures, process understanding, panel attentiveness and the correct use of the relevant plant process computer displays.
The group examination, which is conducted on the simulator, carries 30 marks for each trainee. Each individual is examined at a selected operating position for a duration of one hour. Teamwork evaluation is based on monitoring, fault diagnosis, procedures usage and compliance, crew communication skill, supervision of local area, conflict resolution and evolution management.
Twenty marks are assigned over the training course to an individual's performance both in the class and at the simulator.
ChasCeNT awards certificates to those candidates scoring at least 75% overall, provided that no critical mistakes were made that could jeopardise plant or personnel safety.
The successful candidates perform their duties as electrical operators (EO), turbine operators (TO) or field operators in the plant. Those who fail the course will perform duties as local operators in the field until management decides that they can retake the course.
SE and SS licences
An operator will first take on the role of an EO in the control room at Chashma. They will then move to being a TO, then a reactor operator, and finally a shift supervisor. An operator can apply for a shift engineer licence after three years duty at the plant. Similarly, a shift engineer can apply for the shift supervisor licence, the highest award available, after three years duty at the plant as a reactor operator and shift engineer licence holder.
The plant management conducts written tests and internal interviews of candidates applying for the shift engineer and shift supervisor licences with the support of the Pakistan Nuclear Regulatory Authority (PNRA), the body that oversees all matters relating to nuclear safety and radiation protection. The PNRA's examination team with one expert from each area regarding plant, safety and health physics examines the candidates against pre-designed simulator scenarios followed by the final oral examination. It issues licences to successful operators, and cancels them if the operators are not following the regulations.
Over time, people's knowledge and skill reduce and fade away when there is no repetition and practice.
To learn the best response to emergencies, PNRA requires refresher simulator training for the operators after every six months of operational duty at the plant. A new crew of 8-9 engineers from the plant arrives at the training centre each month. The instructor, in co-operation with the shift supervisor, designs the training scenarios, with an adequate level of challenge, representing the possible malfunctions and accidents at the real plant.
The shift supervisor holds a fixed position, but all the other crew members are shifted to each operating position on the simulator. The training exercises are recorded in writing in the logbooks. At the end of the re-training month, special training in special scenarios is given to those recommended by the shift supervisor.
• Displaying video films to training crews depicting international plant operation practices. On some occasions, science fiction movies are shown to relax the operators.
• The arrangement of plant-specific and engineering or scientific seminars and workshops in collaboration with internal and IAEA experts.
• Providing training to newly employed maintenance staff about engineering fundamentals, plant familiarisation, industrial safety, health physics, management and administrative affairs.
• Arranging visits to other power plants and engineering industrial facilities.
All simulator instructors at ChasCeNT are licence holders. As a result of this, the centre has received a good practice award from a pre-OSART mission.
Power plant safety and long-term commercial operation demands skilled and well-trained operators to diagnose the frequent fault symptoms efficiently. Simulator training increases the operator comprehension and response to infrequent incidents with a high degree of realism. It has a positive effect, and strengthens the operators' performance and leads to improved plant safety. It enables assessment of skills like monitoring, decision-making and crew communication that are extremely difficult to estimate with written tests. The simulator is an ideal tool to assess the competency of operators in all aspects of plant operation.
ChasCeNT is the first simulator training facility for a nuclear power plant in Pakistan, and is still passing through its nascency, but it is intended to make every effort to bring it to world-class standards in improving course structure and training effectiveness. To increase the problem solving skill of operators, new simulator-based exercises with multiple failures are being constantly developed.