The plenary session started with a dialogue designed to share the personal experiences of key experts from past major accidents, discuss the nature of the lessons learned, and evaluate the impact on their life and career. The focus was on a fundamental question: how does the industry deal with human factors in comparison with technological factors during incident investigation and in its subsequent preventive actions. The session was moderated by M. Haage (IAEA).
V.N. Abramova, Head of Science Research Centre ‘Prognoz’;
B. Stoliarchuck, State Nuclear Regulatory Inspectorate Ukraine; and A. Kawano, Tokyo Electric Power Company (TEPCO), shared personal experiences from the Chernobyl and Fukushima Daiichi nuclear accidents, pointing out a number of common features in terms of the human side of the accidents. The shift personnel proved to be extremely courageous when responding to the accidents, and did not abandon the plant despite the dangerous conditions they were forced to deal with, including elevated levels of radiation, lack of supplies, missing or unreliable communication channels and insufficient information about their relatives. Difficult conditions continued beyond the initial accident, with fear of further explosions in the Chernobyl Unit 4 reactor and with 463 aftershocks occurring in the region of the Fukushima Daiichi plant in the first week after the accident.
The different roles of each witness to the accidents provided different personal stories. Stoliarchuck, who was lead engineer of reactor control at Chernobyl Unit 4, recalled thinking that it was not possible, when the control panel in the control room of Unit 4 showed that reactor 4 stopped existing.
Abramova investigated the feelings and behaviour of the personnel and attempted to understand what they were experiencing during the accident in order to indicate
both the causes of the Chernobyl accident and to study how society treated those people who sacrificed themselves for the sake of our welfare.
Kawano described the earthquake that triggered the tsunami which damaged the Fukushima Daiichi plant as a “very, very long horizontal movement when all employees were trying to hide under the tables”. Reiterating the alarming working conditions under which 700 employees were forced to work for several days, Kawano mentioned also very simple but unexpected human issues that needed to be dealt with such as the sanitary conditions; they only had two temporary bathrooms for several hundred people.
The discussion concluded by addressing Haage’s final question: if there is one thing you can do better in terms of the human side of safety, what would it be? It was argued that despite the fact that management devotes 90–95%
of its time to work with people and only 5–10% to work with equipment, educational institutions devote very little time on teaching how to perform this management task. The panellists agreed that lessons learned from disciplines such as ergonomics and psychology need to be reinforced in those institutions educating future engineers. Furthermore, experts asked for more efforts to be put into creating a working environment that would facilitate collaboration between people, both between corporate headquarters and the site, and between managers and workers. At the same time, safety awareness also needs to be enhanced, for example through workshops and seminars, as stressed by Kawano, who described TEPCO’s newly established Nuclear Safety Oversight Office, which has organized such training for senior management.
V.N. Abramova, Head of Science Research Centre ‘Prognoz’ questioned whether we have learned the lessons from the Chernobyl accident and identified what still needs to change. Abramova emphasized the fact that each aspect of safety culture has a psychological component and that this needs to be taken into consideration by everyone involved in the nuclear industry.
A precursor for actually addressing and learning from lessons is to ensure proper understanding of what a lesson really means. The most important is to acknowledge that the event happened, along with all the relevant circumstances.
It is necessary to look both at the individuals directly involved, and at society as a whole, in order to understand how the event is both perceived and reacted to.
Moreover, if a lesson is to be considered as learned, it is necessary to establish a psychological barrier that prevents people from repeating the mistake. It was stressed that only when a taboo is created can a lesson be regarded as properly learned.
Abramova referred to a summary developed by Stoliarchuck describing the Chernobyl accident from the psychological point of view. The conclusion, based on the Minnesota Multiphasic Personality Inventory test, was that the personnel who could have been the direct cause of some of the erroneous actions that led
to the accident were not different from the personnel of any other nuclear power plant. This implies that whoever is involved in decision making at any level of responsibility has to be fully appraised of the potential consequences of their errors: at the end of the day, it is still about people depending on each other and on their colleagues. That is why there is a need to develop relations with workers and to acquire and develop two types of human capital: professional personality formation and human resource management.
Concluding the talk, Abramova argued that the future approach to safety has to be systemic and carried out in two areas: first from a retrospective perspective;
looking at human factors and concentrating on finding what is needed to be done differently in order to avoid repeat events; second, from a prospective perspective by looking at the science of designing people’s behaviour and attitudes. In the latter, more attention needs to be paid to operator behaviour, to the ergonomics and design of the workplace, and to operator reliability and the quality of their attitudes towards nuclear safety and safety culture concepts.
A. Kawano, General Manager of the Nuclear Safety Management Department at TEPCO, presented a paper by T. Anegawa, Chief Nuclear Officer (CNO) of TEPCO. Kawano explained the story of Unit 1 of the Fukushima Daiichi nuclear power plant after a 15 m tsunami triggered by a 9.0 magnitude earthquake washed over the plant. Kawano focused on the operation of the isolation condenser (IC), which caused several misunderstandings. These prevented the personnel from performing the necessary actions in responding to the accident.
Kawano explained that after the earthquake, the IC was working well, but mainly due to poor communication, the shift supervisor understood from the senior supervisor that the IC was not in operation. This assumption was based on the status (i.e. presumed loss) of AC/DC power. An IC is in operation if steam is coming out from its ‘pig’s nose’ pipe so the shift supervisor asked the Emergency Response Centre (ERC) to observe if there was any steam coming out. The ERC reported back that there was a very small amount of steam. The shift supervisor, along with the ERC team, understood that the IC would be in operation only if there was a lot of steam, so he took the information received as confirming that the IC was not operational. In hindsight, the ERC team was not competent and knowledgeable enough to assess the state of the IC properly. The situation was made even worse by the absence of clarification between the shift supervisor and the deputy team leader of the ERC in the main control room about their understanding of the ERC.
Kawano explained that the lack of operational knowledge, miscommunication and a gap in understanding (and other human factors) not only caused the alarming situation of the plant to deteriorate, but also prevented operational measures which otherwise would have been taken to respond to
the accident. TEPCO has kept these human factors in mind when addressing the lessons to be learned. It has introduced several improvements, including an ICS (Incident Command System) designed to limit the number of subordinates and managers to 3–7 people for decision making during accident response. The strategic and planning group has been separated from the implementation group and communication tools have also been improved, introducing satellite phones or radio communication tools to enhance the quality of communication between control rooms and the ERC. A more comprehensive overview on progress made since 11 March 2011 was offered in a second presentation by Kawano (see Summary of Plenary Session in these Proceedings, “Future Perspectives”).