Survey of awareness of radiation disasters among firefighters in a Japanese prefecture without nuclear power plants.

Japanese firefighting organisations are essentially run as village, town, or city units. The Great Hanshin Earthquake of 1995 led to the establishment of emergency support teams to ensure rapid action in response to disasters beyond the capacities of local fire departments. The 2011 Great East Japan Earthquake involved both a tsunami and a radiation disaster caused by a nuclear reactor meltdown, underscoring the need for responses in complex disasters. This study aimed to assess Nagasaki Prefecture firefighters' preparedness for, awareness of, and anxiety regarding radiation disaster response with the aim of elucidating the factors affecting individuals' decisions to accept or reject assignment to a radiation disaster response team. A questionnaire survey was carried out with 1,122 firefighters in three firefighting departments in Nagasaki Prefecture, which does not have nuclear power plants. In total, 920 questionnaires were returned, and the 784 that were valid were analysed. Among the participants, 39% replied that they would have no difficulty accepting assignment to a radiation disaster response team; most of them were under 30 years old and unmarried. This group also included significantly higher percentages of participants who were confident about radiation disaster response or, if anxious, believed things would turn out fine, as well as those who replied that they were able to use the necessary equipment. Furthermore, this group had significantly higher percentages of participants who replied that they would definitely participate in seminars and those who replied that their level of preparedness for radiation disasters was sufficient. The willingness to be assigned to a radiation disaster response team was linked to confidence about radiation disaster response and about handling materials and/or equipment. Therefore, it is considered that measures to increase firefighters' confidence regarding response to radiation disasters will be linked to more proactive measures if and when such disasters occur.

Introduction

In Japan, the rationale for firefighter activities is stipulated in Clause 1 of the Fire Organization Law, as follows [1]:

Firefighting involves the use of facilities and personnel in order to protect the lives, physical health, and property of citizens against loss due to fires; prevent disasters due to fires, floods, earthquakes, and so on; reduce injuries and other harm caused by such disasters; and carry out appropriate activities for the transport of persons injured by disasters, and so on.

On the basis of this law, firefighters are expected to respond promptly to the various types of disasters that occur in Japan.

In Japan, earthquakes, typhoons, and cloudbursts are an annual occurrence, and in recent years, disasters have become especially complex and diverse. For example, disasters in the recent past include the avalanche in Nasu, Tochigi Prefecture, on 27 March 2017, in which eight people died and 40 injured, and the volcanic eruption of Mt. Ontake on 27 September 2014, in which 58 people died, 69 were injured, and five remain missing. There have also been disasters in built-up places, such as the warehouse fire in Miyoshi, Saitama Prefecture, on 16 February 2017, which took firefighters 13 days to extinguish. Then, there was the West Japan Railway Co.’s Fukuchiyama Line derailment, which happened in an urban area on 25 April 2005 and resulted in as many as 107 deaths and 549 injuries. Finally, a fire at Bridgestone’s Tochigi Plant, in Kuroiso, Tochigi Prefecture, on 26 September 2003, resulted in 5,032 people from 1,708 households in seven wards being evacuated for two days. Thus, disasters that are large-scale in terms of severity and the number of people affected occur quite frequently.

Climate change is leading to more severe natural disasters, and urban development is leading to increasingly complex and diverse disasters that necessitate a specialised approach to management. Firefighters are expected to respond to these promptly and therefore prepare for them on a daily basis.

In accordance with the relevant laws, firefighting organisations in Japan operate as city, town, and village units. In one of these laws, the role of municipalities is stated as follows:

To ensure such continual and steady improvement and strengthening of the fire service strength, municipalities must perform certain tasks while implementing the strict safety management of fire personnel. These tasks include (i) improvement and strengthening of the fire suppression system through the advancement of fire defence tactics and fire equipment so that various types of disasters can be dealt with in a precise manner, (ii) improvement and strengthening of the fire prevention system in response to the higher demand for and specialisation of fire prevention work which have resulting from the growing size and complexity of buildings, (iii) improvement and strengthening of the ambulance service system in response to the growing number of ambulance runs and demand for a higher quality ambulance service which have resulted from the progress of the ageing society, (iv) improvement and strengthening of the rescue system to conduct rescue operations in a precise manner at the time of disasters of which the complexity and diversity have been growing and (v) improvement and strengthening of the system to implement measures designed to protect the public in an armed attack and other situations. Moreover, consolidation of a wide area fire service system, including emergency fire response teams, is required to strengthen the preparedness against such large‐scale natural disasters as earthquakes, violent storms and floods. [2]

Firefighters work at all fire departments run by city, town, and village governments. After learning firefighting fundamentals (e.g., fire suppression, first aid, rescue, and prevention) at fire and disaster management colleges, which are mostly run by prefectural governments, firefighters are employed within organisations defined by each fire department in accordance with the relevant city, town, or village’s population, area, types of buildings, and the like. The fire department’s main categories of tasks are fire suppression, first aid, rescue, communication, and prevention. Concurrent performance of duties is permitted, depending on each department’s size and circumstances.

Because of the Great Hanshin Earthquake on 17 January 1995, emergency firefighting support teams, along with an organisation for mutual support between firefighting bodies throughout Japan, were established in June 1995. These teams were legally established in April 2004 by an amendment to the Fire Organization Law and have since been able to respond to a wide variety of disasters [3]. When a fire disaster occurs, the governor of the prefecture where the disaster is located submits a mobilisation request to the commissioner of the Fire and Disaster Management Agency, who then submits dispatch requests to the governors of prefectures and/or mayors of cities, towns, and villages other than where the disaster has occurred. The fire departments that receive these requests then marshal and mobilise emergency firefighting support teams, as prefecture-based units, and thus actively respond to the disaster at the site where it has occurred. Therefore, each fire department, based on instructions from the relevant prefectural government, records the teams and personnel that can be dispatched in the event of a request and prepares for such a request. In terms of selection of teams to dispatch, individuals and teams are designated in accordance with conditions in each fire department such as the department size.

Among the disasters to which the emergency firefighting support teams have responded, the Great East Japan Earthquake on 11 March 2011, was one such as had not previously occurred in Japan. In addition to the earthquake and tsunami, there was a radiation disaster caused by an incident at Tokyo Electric Power Co.’s Fukushima Daiichi Nuclear Power Plant (hereafter ‘Fukushima Daiichi Disaster’). Firefighting organisations throughout Japan mobilised as many as 31,166 emergency support teams consisting of 109,919 personnel, and activities at the disaster site continued for 88 days [4]. In addition, with respect to the Fukushima Daiichi Disaster, as well as the firefighters at the fire department responsible for that location, nine other fire departments dispatched a total of 136 emergency support teams, for a total of 664 personnel. Tokyo Electric Power Co. also hired 12 firefighting pump engines from eight fire departments [5].

After the establishment of the emergency firefighting support teams, from June 1995 to September 2017, they went into action 34 times, and there have been multiple mobilisations a year since 2014. It is expected that situations in which firefighters are active at disaster sites performing duties outside their usual ones, as in the case of the Great East Japan Earthquake, will continue to increase in frequency. The Fukushima Daiichi Disaster was the first large-scale radiation disaster in Japan. There had been no previous incidents that involved a risk of major release of radioactive substances, and it constituted a major turning point for firefighters in terms of the appropriate activities in the event of a radiation disaster. The 2018 White Paper on Fire Service [6], released after the Fukushima Daiichi Disaster, mentions future measures to be taken based on the disaster, referencing how certain health interventions, for example tests using whole-body counters, were given to firefighters on the emergency firefighting support teams involved in responding to the disaster to help reassure them. In addition, health management support was provided, including ensuring opportunities for periodic supplementary tests and long-term monitoring of health conditions among firefighters. Thus, the importance of providing continuing support was recognised. In addition, the paper stated that, in the event of accidents involving release of radiation or radioactive materials that occur either (i) at nuclear energy facilities or facilities where radioisotopes and similar materials are handled or (ii) when transporting radioactive materials, it is essential for the relevant firefighting organisations to respond promptly and appropriately. Thus, it is also essential to continue to improve the firefighting skills of these organisations in relation to accidents involving the release of radioactive materials [6].

From the point of view of firefighters, who must confront various types of disasters, elucidation of the current situation regarding firefighting related to radiation emergencies and the factors affecting timely responses to radiation disasters could inform how to improve preparation for radiation disasters. Previous studies reported the effectiveness of education and training for disaster preparedness or planning [7-10]. Furthermore, Ben Natan et al. examined variables affecting nurse willingness to work at an earthquake site and reported that ‘perceived self-efficacy, level of knowledge, experience and the support of a multidisciplinary staff affect nurse willingness to report to work in the event of an earthquake’ [11]. Radiation disasters are very rare but require specialization. A report about the special disaster, that is, the chemical, biological, radiological and nuclear (CBRN) events reported that “CBRN events are probably more of a means of disorganization and major terror than of mass destruction. During crisis situations, decision-making is most effective when the simplest and most effective ideas are used” [12]. However, there has been no research on disaster preparedness or willingness to work in disasters among firefighters. By eliminating the anxiety of firefighters, cooperation with related parties will be smooth, and firefighters can engage efficiently with peace of mind while ensuring safety. In this context, a survey was carried out with firefighters in Nagasaki Prefecture, which does not have nuclear power plants. The aim was to assess the preparation for, awareness of, and anxiety regarding responses to radiation disasters, with the aim of determining the factors influencing individuals’ decisions to accept or refuse assignment to a radiation disaster response team when this possibility is proposed.

Materials and methods

This survey was carried out from November to December 2016 with 1,122 firefighters at three fire departments in Nagasaki Prefecture and covered all personnel in each fire department. These personnel engage in five tasks: fire suppression; first aid; rescue; communication; and prevention, and sometimes they have overlapping duties. These departments included full-time and specialist rescue teams, as well as full-time staff in command roles, so that few personnel had overlapping duties. Although the three fire departments do not have a specialised section for unique disasters such as those involving nuclear materials, chemicals, or biohazards, they do have personnel engaged in communication and prevention who may be called on to work in these kinds of disasters.

We conducted a questionnaire survey with all participants. We delivered the explanatory documents about the survey and the answer sheets to the fire departments in the same envelopes, and then distributed them to all respondents. Respondents placed the completed answer sheets in the same envelopes used for distribution. The fire departments collected these, which were received by the researchers. We understood returning a completed questionnaire as providing consent to participate in the study. Participants were allowed to leave questions blank if they did not wish to provide an answer; completely blank questionnaires were discarded. Partially completed questionnaires were also accepted and included in this study.

The principal contents of the questionnaire were respondents’ attributes, awareness about the effects of nuclear incidents, and awareness about radiation disasters. To explain the above in more detail, on the basis of their attributes, participants were categorised by age, marital status, duration of service, details of duties, experience, and number of mobilisations to large-scale and radiation disasters.

The items relating to awareness about the effects of nuclear incidents were as follows: interest in events at the time of nuclear incidents, awareness of the effects of nuclear incidents on participants’ own health, awareness of the effects of nuclear incidents on the health of adults and children, and awareness of genetic effects.

The items relating to awareness about radiation disasters were as follows: potential for a nuclear disaster in the area where one is stationed, level of confidence in responding to radiation disaster, understanding of the details of firefighting teams’ activities at the time of the Fukushima Daiichi Disaster, experience of attending lectures about radiation disasters and/or emergency exposure situations, participants’ own competence at using the materials and/or equipment for radiation disasters, understanding of the manual, wish to participate in future seminars about radiation disasters, participants’ response if voluntary transfer to a team that is mobilised preferentially for radiation disasters is proposed, views about voluntarily working in an area where the air radiation dose rate has been measured to be 100 mSv/year, if this is proposed, and participants’ own preparedness for future radiation disasters (see Supplementary Materials of S1 Data for specific details of questions and responses).

Of the 1,122 firefighters who responded, it was confirmed from their names that 14 were women. However, as this number was small and there were concerns about identifying individuals from the contents of the replies, a question concerning gender was not included.

In relation to the replies to the questions about attributes, awareness about the effects of nuclear incidents, and awareness about radiation disasters, the factors affecting the willingness to be assigned to a radiation disaster response team were analysed using the χ2 test and ordinal logistic regression analysis. The software used for statistical analysis was SPSS (version 24; IBM). The significance level was set at p<0.05.

In accordance with the Ethical Guidelines for Medical and Health Research Involving Human Subjects published jointly by the Japanese Ministry of Education, Culture, Sports, Science, and Technology and the Ministry of Health, Labour, and Welfare, this study was approved by the Ethics Committee at Nagasaki University Graduate School of Biomedical Sciences (approval no.: 16092399).

Results

Of the 1,122 questionnaires distributed, 920 were returned (response rate: 81.9%). The number of blank and incomplete questionnaires was 15 (1%) and 121 (10%), respectively. After excluding these, 784 valid questionnaires (valid response rate: 70%) were analysed.

The distribution of participants by age group was as follows: under 30: 31%; 30–39: 21%; 40–49: 19%; 50–59: 21%; and 60 and over: 8%. Married and unmarried participants corresponded to 76% and 24%, respectively. The distribution of different durations of service was as follows: less than six years: 21%; 6–10 years: 19%; 11–20 years: 16%; 21–30 years: 16%; 31–40 years: 21%; and over 40 years: 7%. The percentages of different duties were as follows: mainly fire suppression duties: 50%; first-aid duties: 21%; routine administrative duties: 13%; rescue duties: 12%; and command duties: 4% (Fig 1). Participants with and without experience of mobilisation to large-scale disasters corresponded to 27% and 73%, respectively. Of those with experience, the percentages of mobilisations were as follows: once: 77%; twice: 10%; thrice: 2%; and four times or more: 11%. Only one participant reported having been mobilised for a nuclear incident or radiation disaster.

Fig 1

Attributes of participants.

(a) Age (years), (b) Marital status, (c) Duration of service (years), (d) Details of activities.

The percentage of participants who replied that they would accept assignment to a team that would be mobilised preferentially in the event of a radiation disaster without hesitation was 39% (Fig 2A). We analysed factors associated with willingness to accept assignment without hesitation using the χ2 test. Significant correlations were found with age, marital status, awareness of the health and/or genetic effects of nuclear incidents, confidence about response to radiation disasters, competence in using materials and/or equipment for radiation disasters, future willingness to participate in seminars, and whether the participant’s preparedness for a radiation disaster was sufficient (Tables 1 and 2). More participants aged under 30/in their 30s (p<0.001) or unmarried (p = 0.004) replied that they would accept assignment to a team that would be mobilised preferentially in the event of a radiation disaster without hesitation than other participants, and this result was significant. Regarding awareness about the effects of nuclear incidents, more participants who considered that nuclear incidents do not affect health (p<0.001) or genetics (p<0.001) replied that they would accept assignment without hesitation, which was also significant. In the analysis of awareness of radiation disasters, a significantly high percentage of participants who would unhesitatingly accept assignment answered that they thought the potential for a nuclear disaster in the area where one is stationed was possible (p = 0.011), and they had confidence, even if they had anxiety, in responding to radiation disasters (p<0.001). Furthermore, regarding participants’ own competence at using materials and/or equipment for radiation disasters, there was a significant relationship between participants who answered ‘I can use them’ and those who were willing to accept assignment without hesitation (p = 0.016). For education and preparation, there was a significant relationship between participants who would definitely participate in future seminars about radiation disasters (p<0.001) and those who were sufficiently prepared for future radiation disasters (p<0.001) and accepting assignment without hesitation.

Fig 2

Opinion about radiation disasters.

(a) Whether I would accept an assignment with a radiation disaster response team. (b) Conditions under which I would accept assignment. (c) Reasons for refusing assignment.

Table 1

Factors correlated with opinion about assignment to radiation disaster response team: Attributes and awareness about the effects of nuclear incidents.

Variable	Accept without hesitation N = 309 (%)	Accept with conditions N = 304 (%)	Refuse N = 171 (%)	P-value
Age (<30/30s/40s/50s/ ≥60)	115/77/50/60/7 (37/25/16/19/2)	88/64/69/66/17 (29/21/23/22/17)	40/26/25/41/39 (23/15/15/24/23)	<0.001
Married/unmarried	215/94 (70/30)	236/68 (78/22)	141/30 (82/18)	0.004
Nuclear incidents have health effects* (yes/no)	264/45 (85/15)	293/11 (96/4)	162/9 (95/5)	<0.001
Nuclear incidents have genetic effects* (yes/no)	241/68 (78/22)	273/31 (90/10)	150/21 (88/12)	<0.001

*Yes: ‘I think there are effects’ or ‘If I have to choose, I think there are effects’; No: ‘If I have to choose, I think there are no effects’ or ‘I think there are no effects’.

Table 2

Factors correlated with opinion about assignment to radiation disaster response team: Awareness about radiation disasters.

Variable	Accept without difficulty N = 309 (%)	Accept with conditions N = 304 (%)	Refuse N = 171 (%)	P-value
Possibility of radiation disaster at station (yes/no)	201/108 (65/35)	214/90 (70/30)	97/74 (57/43)	0.011
Confidence about response to radiation disaster (confident/anxious/not confident)	133/176 (43/57)	79/225 (26/74)	26/145 (15/85)	<0.001
Activities of firefighting team at time of nuclear incident (aware/unaware)	243/66 (79/21)	244/60 (80/20)	124/47 (72/28)	0.138
Attend lectures about radiation disasters, etc. (yes/no)	151/158 (49/51)	157/147 (52/48)	69/102 (40/60)	0.058
Using materials and/or equipment for radiation disasters* (can use/not confident/cannot use)	78/161/70 (25/52/23)	55/179/70 (18/59/23)	22/77/72 (13/45/42)	<0.001
Manual for Firefighting Activities at Nuclear Power Facilities** (familiar or comprehensible/incomprehensible)	98/211 (32/68)	98/206 (32/68)	39/132 (23/77)	0.068
Participation in seminars about radiation disasters*** (will participate/will consider/will not participate)	73/202/34 (24/65/11)	65/201/38 (21/66/13)	13/91/67 (7/53/40)	<0.001
Preparedness for radiation disasters (fully prepared/partly prepared/unprepared)	9/183/117 (3/59/38)	1/148/155 (0/49/51)	2/59/110 (1/35/64)	<0.001

*Can use: able to use the materials and/or equipment; not confident: understand their details and location; cannot use: not able to use them.

**Familiar: fully comprehensible; understood: largely comprehensible.

***Will participate: will definitely participate; will consider: participation would be acceptable; will not participate: will probably not participate, or will not participate.

Ordinal logistic regression analysis of factors with independent relationships with acceptance of assignment to radiation disaster response teams revealed that participants who answered as follows were significantly more likely than those who gave other answers to accept assignment without hesitation: (i) ‘I am confident about dealing with radiation disasters’ (p<0.001), (ii) ‘I can use the relevant materials and/or equipment’ (p = 0.016), and (iii) ‘I will definitely participate in future seminars’ (p = 0.001) (Table 3).

Table 3

Independent factors correlated with opinion about assignment to radiation disaster response teams.

	B	95% confidence interval
		Lower limit	Upper limit	Significance level
Nuclear incidents have health effects (yes/no)	-0.902	-1.942	0.139	0.089
Confidence about response to radiation disasters (confident/anxious/not confident)	0.829	0.477	1.180	<0.001
Using materials and/or equipment for radiation disasters (can use/not confident/cannot use)	0.291	0.055	0.528	0.016
Participation in seminars about radiation disasters (will participate/will consider/will not participate)	0.688	0.285	1.091	0.001
Preparedness for radiation disasters (fully prepared/partly prepared/unprepared)	0.255	-0.042	0.553	0.092

Regarding participants who replied that they would accept assignment to a radiation disaster response team under certain conditions, the results were as follows: sufficient education and training before assignment: 30%; satisfactory personal equipment and health checks: 30%; continued education and training: 23%; and good pay: 16%. Reasons for refusal of assignment to a radiation disaster response team were the following: anxiety owing to family: 42%; danger associated with radiation disasters: 34%; the belief that people must willingly work under such circumstances: 12%; and aversion to being subjected to more education and training: 2% (Fig 2B and 2C).

With respect to the willingness to work where the radiation dose rate in the air has been measured to be 100 mSv/year, 54% of participants replied that they would agree if proposed. The different reasons for this willingness were as follows: being a firefighter: 82%; that 100 mSv/year has no effect on health: 7%; and inability to refuse: 8%. The different reasons for refusing to work in such an area were as follows: 100 mSv/year would harm health: 16%; desire to avoid radiation exposure out of concern for the family: 35%; and anxiety owing to lack of experience with radiation disasters: 38% (Fig 3).

Fig 3

Opinion about radiation disasters.

(a) Voluntarily engaging in activities in areas with radiation dose of 100 mSv/year, (b) Reasons for engaging in activities in areas with radiation dose of 100 mSv/year, (c) Reasons for refusing to engaging in activities in areas with radiation dose of 100 mSv/year.

With respect to the wish to participate in future seminars about radiation disasters, 80% of participants replied that they would definitely participate or be willing to participate, which was much greater than the 17% who replied that they would probably participate and the 3% who replied that they would not participate. The different reasons for not wanting to participate in seminars were as follows: infrequency of radiation disasters: 31%; being busy with other things: 29%; scepticism about the benefits of participation: 27%; and already having undergone education and training: 4% (Fig 4).

Fig 4

Participation in seminars about radiation disasters.

(a) Wish to participate in seminars, (b) Reasons for not participating in seminars.

Discussion

In this study, we found that 39% of firefighters in Nagasaki Prefecture would have no problem being assigned to a team that would be preferentially mobilised to respond to radiation disasters. Study participants who were confident about dealing with radiation disasters, able to use the relevant materials and/or equipment, and would participate in relevant seminars were significantly more likely than others to report a lack of hesitation regarding being assigned to such a team.

The Ministry of Internal Affairs and Communications has released several documents providing guidelines for firefighters responding to radiation disasters in Japan, including the Manual for Firefighting Activities at Nuclear Power Facilities, Etc. [13] and Start! RI119: Basic Knowledge for Responses to Radiation Disasters by Firefighters [14], and various fire departments have prepared their own manuals for responding to radiation disasters based on these. Fire academies in each prefecture have also planned educational programmes relating to radiation disasters, depending on the situation in each area, and currently invite specialists to hold lectures and provide practical training. In addition, in recent years, numerous books and other documents have been published about responding to various types of radiation disasters, and the opportunities for firefighters to become acquainted with these have increased. Furthermore, so that the materials and/or equipment they have can be used effectively, training based on the manuals is provided routinely, and the materials and/or equipment are upgraded as necessary. In our study, 42.8% of participants were familiar with or said that the Manual for Firefighting Activities at Nuclear Power Facilities was comprehensible. Ahayalimudin N et al. [15] reported almost all (93%) emergency medical workers agreed on the importance of reading and understanding their institution’s disaster management plan, and the majority were willing to be involved in disaster management, but half felt they did not have the responsibility to assist disaster victims with their basic needs. In our data, there was no association between the frequency of participants who were familiar with the manual and their opinion about assignment to a radiation disaster response team, meaning that it is important to not only prepare and maintain a manual but also to conduct useful training with the manual. Globally, although there are differences in systems between countries in terms of governmental jurisdiction, actual tasks, and so on, firefighters respond to similar types of disasters, including radiation disasters, in each country and region [16-21]. For example, in the case of Norway, in addition to the existence of an emergency preparation protocol, training within the organisation is particularly important [22].

The results of the present study show that firefighters’ activities when radiation disasters occur are affected by their level of confidence in their capacity to respond appropriately to the disaster. This confidence involves their pre-disaster experience as well as their skill at disaster response and handling the relevant materials and/or equipment. Regarding response to radiation disasters, participants who were confident or anxious but believed that things would turn out fine were significantly more likely to have no difficulty with assignment to a radiation disaster response team than others. However, 70% of participants replied that they were not confident; therefore, although firefighters who have to confront radiation disasters are provided with books and educational programmes, and training is carried out when materials and/or equipment are upgraded, it is possible that these measures are not put into practice and do not lead to increased confidence.

Of all participants, 78% replied that they would either accept without hesitation or accept under certain conditions assignment to a radiation disaster response team if proposed. In addition, 54% of participants replied that they would accept if the possibility of voluntarily engaging in activities in areas with air radiation dose rates of 100 mSv/year were proposed.

A previous study [23] about the willingness of civil defence and firefighting programme students to work in disasters after graduation reported only 42% of students were willing to work in nuclear accidents. The study also reported 46.3% of the students ‘wanted to work in disasters because they wanted to help people’, and only 22.4% thought that difficult and uncomfortable conditions would reduce their willingness to work [23]. Therefore, even student firefighters have a sense of mission to save lives or help people. Considering that 82% of participants in our study gave ‘being a firefighter’ as the reason why they would accept assignment to a disaster response team, this willingness can be attributed to the fact that firefighters are habituated to confronting disasters and exemplifies the strength of their perception of their mission as requiring them to respond even to radiation disasters.

According to a radiation risk awareness survey [24] performed with firefighters in Aomori Prefecture, which does have nuclear energy facilities, the firefighters had few uncertainties or anxieties about radiation. However, it should be noted that personnel at fire departments in prefectures with nuclear energy facilities have raised concerns about the safety of disaster responses and facilities as well as insufficient knowledge and understanding of radiation by personnel at fire departments in prefectures without nuclear energy facilities. It is thus necessary to prepare a curriculum for specialists in radiation disasters, to improve the skills of individual personnel by means of lectures and seminars, and to increase knowledge and understanding so as to enable team-based disaster responses [24]. Another study [25] on factors affecting emergency medical workers’ disaster response competency reported participation in disaster education or training two or more times annually was significantly associated with competency. It also reported disaster risk perception, self-efficacy for disaster, and personal disaster preparedness predicted disaster response competency. A systematic review of disaster preparedness among nurses found that previous disaster response experience and disaster-related training increase disaster response preparedness [26]. In fact, provision of high quality and carefully structured education and training courses and proactive participation in the seminars may be the most important factor for improving individual attitudes. In the present study, continuing education and training was put forward as a condition for accepting assignment to a radiation disaster response team, but some participants replied that they had doubts about the value of participating in seminars. However, irrespective of the willingness to accept a nuclear disaster assignment, the level of interest in participating in seminars about radiation disasters was high, and the importance of training for radiation disasters was recognised. This suggests that when seminars and continued training are provided, measures and approaches that enable individuals to raise their confidence about the appropriate responses and handling the relevant materials and/or equipment before a radiation disaster has occurred should be included.

Measures such as the above have already been attempted by Kobe Municipal Fire Dept. In October 2007, the agreement “Memorandum on Cooperation in Times of Specialized Disaster” [27] was signed by the Kobe Municipal Fire Dept. and Kobe Gakuin University; later, other parties also signed the memorandum, these being Kobe Pharmaceutical University in August 2008 [28] and Kobe University in March 2012 [29]. The memorandum’s contents include (i) support and cooperation in relation to radiation and other specialised disasters; (ii) provision of education and training courses to firefighters, collaborative research, holding public seminars, and so on, from before such disasters occur; and (iii) education of students about preventing fires and other disasters, with firefighters as lecturers [29-31]. Based on this memorandum, the education, training, and so on necessitated by either party’s circumstances are to be provided. However, considerable work remains to be done to verify its effectiveness.

This study involved a questionnaire survey with firefighters in Nagasaki Prefecture, which does not have nuclear power plants. However, Nagasaki suffered from fallout from the atomic bomb in 1945. In 1943, during World War II, the national government established a policy of expanding the government-run firefighting organisations in all important Japanese cities. As a result, one fire station was opened in Nagasaki and one nearby in Sasebo; established within the national police organisation, these two fire stations were the first specialised, government-run firefighting organisations in Japan. However, as that was during the war, unlike the current situation, the firefighting activities focused on fires due to aerial bombardment. It was during that time that the atomic bomb was dropped on Nagasaki, at 11:02 on 9 August 1945, causing 73,884 deaths and 74,909 serious injuries, with 12 deaths and 26 injuries among firefighters. Of the 145 firefighters in Nagasaki at that time, 98 were left after deaths and retirements from injury. After the war, the Fire Service Law was put into effect on 7 March 1948, and city, town, and village fire departments were set up, independently of the police, leading to the current system [32]. With respect to firefighting organisations’ records, records of injuries at the time of the atomic bombardment have been kept, but there are no records of the response to the radiation disaster or of relevant education and training from that time to the present day. However, education and training about radiation disasters are currently being provided as an aspect of the training for nuclear-biological-chemical (NBC) disasters.

Of course, not all firefighters in this study are from Nagasaki Prefecture, but they may have some knowledge of atomic bomb and radiation exposure after working in this area. Nevertheless, some participants replied that they had doubts about the value of participating in seminars while firefighters’ activities when radiation disasters occur are affected by their level of confidence. On the other hand, Ahayalimudin et al. [15] reported that emergency medical personnel’s education level and disaster training attendance was significantly associated with increased knowledge and practice scores and with higher practice scores, respectively. These results suggest it is important to provide a special education programme that focuses on radiation disasters only for firefighters even if they already have some knowledge about radiation exposure.

This study has several limitations. First, among the participants, only one replied that only one indicated having experience in responding to a radiation disaster. It was, therefore, not possible to investigate whether experience with a radiation disaster had any effect on confidence about response to radiation disasters or about handling the relevant materials and/or equipment. Second, the fire departments covered by this study were in Nagasaki Prefecture, and, as there were only three of them, questions about age, gender, and station site were omitted to avoid identifying individuals. If future studies include more firefighters who have experience with radiation disasters and those stationed at fire departments in prefectures that have nuclear power plants, and/or make comparisons between fire departments of approximately equal size in different prefectures, they can be expected to provide additional information that will be useful for making satisfactory preparations for radiation disasters.

The present study found that willingness to accept assignment to a radiation disaster response team was correlated with individual confidence about response to radiation disasters and about handling relevant materials and/or equipment. For this reason, it is considered useful to have continuing educational programmes that combine basic knowledge and practical competence. In the future, the aim is to take measures that reduce anxiety and increase confidence among firefighters regarding response to radiation disasters, including liaison between fire departments and institutions with specialised knowledge, such as medical centres for people with severe radiation exposure; establishment of seminar programmes specifically for firefighters; and establishment of face-to-face relationships, starting before disasters occur, between firefighting bodies that respond promptly to disasters and other organisations involved with disasters. It is hoped that these measures will facilitate vigorous and proactive activities when disasters strike.

(DOCX)

Click here for additional data file.

23 Apr 2020

PONE-D-19-32209

Survey of awareness about radiation disasters among firefighters in a Japanese prefecture without nuclear power plants

PLOS ONE

Dear Dr. Hayashida,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that carefully and systematically addresses all the points raised by Reviewers 1 and 2 during the review process (see below).

We would appreciate receiving your revised manuscript by Jun 07 2020 11:59PM. When you are ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter.

To enhance the reproducibility of your results, we recommend that if applicable you deposit your laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

Please include the following items when submitting your revised manuscript:

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). This letter should be uploaded as separate file and labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. This file should be uploaded as separate file and labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. This file should be uploaded as separate file and labeled 'Manuscript'.

Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.

We look forward to receiving your revised manuscript.

Kind regards,

Emmanuel Manalo, PhD

Academic Editor

PLOS ONE

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

1. We note that you have indicated that data from this study are available upon request. PLOS only allows data to be available upon request if there are legal or ethical restrictions on sharing data publicly. For information on unacceptable data access restrictions, please see http://journals.plos.org/plosone/s/data-availability#loc-unacceptable-data-access-restrictions.

In your revised cover letter, please address the following prompts:

a) If there are ethical or legal restrictions on sharing a de-identified data set, please explain them in detail (e.g., data contain potentially identifying or sensitive patient information) and who has imposed them (e.g., an ethics committee). Please also provide contact information for a data access committee, ethics committee, or other institutional body to which data requests may be sent.

b) If there are no restrictions, please upload the minimal anonymized data set necessary to replicate your study findings as either Supporting Information files or to a stable, public repository and provide us with the relevant URLs, DOIs, or accession numbers. Please see http://www.bmj.com/content/340/bmj.c181.long for guidelines on how to de-identify and prepare clinical data for publication. For a list of acceptable repositories, please see http://journals.plos.org/plosone/s/data-availability#loc-recommended-repositories.

We will update your Data Availability statement on your behalf to reflect the information you provide.

Additional Editor Comments (if provided):

Both reviewers note the merits of this paper, but they also point out some very important and necessary modification you need to make before this paper can be considered suitable for publication. So please go through their comments carefully and implement the changes they suggest systematically. I want to emphasize in particular Reviewer 1's comments about the need for a more comprehensive literature review: I myself think that your contextualization of this research within the existing pertinent research literature is very inadequate.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: No

Reviewer #2: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: 1, The authors conducted an important research to facilitate the understanding of the factors affecting individual’s attitudes/decisions towards radiation disaster response. I believe the study has broad impacts, and the results could help develop better disaster preparedness and response. However, the discussion about the intellectual merit of the paper is not enough. How the study would contribute to the existing knowledge of the factors affecting individual’s attitudes/decisions towards disaster preparedness and response is not fully discussed in the paper. I would urge the authors conduct a comprehensive literature review and elaborate the intellectual merits of the paper in both Introduction and Discussion sections.

2. From the lines 145 to 210, the authors explain the survey in detail, and I feel difficult to follow here. The content is helpful for readers to understand the research but also makes the paper tedious. Maybe the authors could find a good way to put it together. For example, the authors could stress some important points in the paper and put more detailed information in the supplemental document.

3. For the chi-square and ordinal logistic regression tests, I would urge the authors either inform the null hypothesis and the alternative hypothesis in the context of study or elaborate what do the results of tests interpret.

4. The discussion related to the results is not sufficient. Also, there are no clear conclusions relevant to the emerging literature. I would urge the authors to revisit some of the literature regarding individual’s attitudes/preferences towards policies of disaster planning and response and discuss how the results could contribute to the existing literature.

5, I suggest that the authors ask for a professional copy editing service. The paper could be greatly improved in terms of the language such as the use of voice, tense, article and the word choice. Also, a common problem is that some sentences are really long and become difficult to follow. The authors could break the long sentences down into several short sentences. I listed some examples that could be improved.

Page 1, line 31-36, line 36-37

Page 2, line 44-49

Page 3-4, line 63-67, line 69 ‘put it out’, line 73-74

Page 5, line 86-90

Page 6, line 97-99

Page 7, line 119-120 and line 121-122 are repetitive.

Page 7, line 121-128 I would suggest that the authors use an active voice instead of a passive voice here.

Reviewer #2: Authors describe a survey of awareness of firefighters for radiation disasters. Results of this survey are important and suggestive for dealing with radiation disasters. However some considerations and improvements in the manuscript will be required.

1. Profile of participants

In this paper, firefighters are classified into 5 categories. Are they engaged in general affairs? I think firefighting department may have the section responsible for special disaster for such as nuclear materials, chemical, biohazards. In this survey, descriptions about firefighters engaged in such works are needed.

2. Significance of survey in Nagasaki “without nuclear plants”

Authors describe Nagasaki as prefecture without nuclear plants. However Nagasaki severely suffered from atomic bomb in 1945. Many people in Nagasaki get intensive education from primary schools. In this point, Nagasaki is different from other prefectures in Japan. Some discussions about this point may be needed.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files to be viewed.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email us at figures@plos.org. Please note that Supporting Information files do not need this step.

6 Jun 2020

We appreciate the time and effort you and each of the reviewers have dedicated to providing insightful feedback on ways to strengthen our paper. We have incorporated changes that reflect the detailed suggestions you have graciously provided. To facilitate your review of our revisions, we replied a point-by-point response to the questions and comments in attached word file named 'response to reviewer'. Could you confirm the attached file? Thank you again.

Submitted filename: Response to reviewers.doc

Click here for additional data file.

13 Jul 2020

Survey of awareness of radiation disasters among firefighters in a Japanese prefecture without nuclear power plants

PONE-D-19-32209R1

Dear Dr. Hayashida,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Emmanuel Manalo, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors addressed the comments and greatly improved the paper. The research is important because there are few studies regarding firefighters' preparedness for and awareness of regarding radiation disaster response. The paper has great potential and still has large room to be improved in terms of language. One suggestion for author's future writing is to use active voice instead of passive voice in scientific writing. For example, 'A questionnaire survey was carried out with 1,122 firefighters in three firefighting departments in Nagasaki Prefecture, which does not have nuclear power plants. In total, 920 questionnaires were returned, and the 784 that were valid were analysed (page 2, line 25-28)' could be improved as 'We conducted a questionnaire survey with 1,122 firefighters participated in three firefighting departments in Nagasaki Prefecture, where does not have nuclear power plants. In total, we received 920 questionnaires and analysed 784 questionnaires that were valid.' Another suggestion is to avoid very long sentences. For example, 'The 2018 White Paper on Fire Service [6], released after the Fukushima Daiichi Disaster, mentions future measures to be taken based on the disaster, referencing how certain health interventions, for example tests using whole-body counters, were given to firefighters on the emergency firefighting support teams involved in responding to the disaster to help reassure them. (page 7, line 138-142)' I would recommend to accept the manuscript.

Reviewer #2: (No Response)

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

15 Jul 2020

PONE-D-19-32209R1

Survey of awareness of radiation disasters among firefighters in a Japanese prefecture without nuclear power plants

Dear Dr. Hayashida:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Professor Emmanuel Manalo

Academic Editor

PLOS ONE