12. Understanding the Impact of Responder Management Strategies on Public Experiences and Behaviour During Mass Casualty Decontamination

Holly Carter¹, John Drury² and Richard Amlôt¹

(1)

Emergency Response Department Science and Technology, Public Health England, Salisbury, UK

(2)

School of Psychology, University of Sussex, Brighton, UK

Richard Amlôt

Email: Richard.Amlot@phe.gov.uk

Keywords

CBRNEffective managementDecontaminationVulnerable groupsShared identity

As demonstrated by the extensive research presented within this volume, there is now a wealth of evidence relating to best practices in terms of optimising physical and technical aspects of skin decontamination in response to chemical, biological, radiological, and nuclear (CBRN) incidents . There is another factor that must also be considered when ensuring that skin decontamination is as effective as possible: will those affected be prepared to undertake recommended decontamination actions? Traditionally, the answer to this question has relied on two (contradictory) assumptions. The first is that people will automatically take actions recommended to them in these situations; they will be frightened and will rely on emergency responders to help them [5, 8]. The second is that people will not take recommended decontamination actions; they will behave in an irrational and disorderly way, and emergency responders will need to control this disorderly and irrational behaviour [5, 12].

However, recent research has demonstrated that public behaviour is much more nuanced in these situations, and that the way in which members of the public behave will be determined in large part by the way in which the incident is managed. This is particularly the case during incidents involving mass decontamination, in which there will be a relatively small number of emergency responders compared to members of the public. When decontamination is required, people will respond both to the perceived threat (the possibility of being contaminated) and the way the threat is managed (actions taken by emergency responders). The way an incident is managed will therefore affect the way members of the public respond. Understanding how responder management strategies can affect public behaviour, and hence the efficacy of decontamination, is crucial to ensuring the success of the decontamination process.

Incidents involving mass decontamination involve intergroup encounters between a crowd and emergency responders, and it is therefore helpful to consider principles from crowd behaviour theories when examining public behaviour during mass decontamination. In particular, the social identity approach [48, 49] has been beneficial in facilitating an understanding of public behaviour in this context. The social identity approach suggests that people have both personal and social identities, and that social identities are based on group memberships. When people come to share a social identity, it affects the way in which they interact with members of their own social group, and also with members of other social groups. In particular, when people share a social identity , they are more likely to cooperate with other group members, and act in accordance with group norms. People come to share a social identity when they perceive themselves as similar to other group members at some level of comparison. Some of the factors that enhance the likelihood of categorising oneself as similar to others include proximity to others, a sense of shared fate with other group members, and the perception of a shared threat; these are all factors that are associated with incidents involving mass decontamination, and hence application of the social identity approach can facilitate an improved understanding of public behaviour in this context.

This chapter has three key aims. First, we will describe research into likely public behaviour during mass emergencies, and demonstrate how the way in which an incident is managed will affect the way in which members of the public respond. Second, we will highlight how an effective responder management strategy can promote positive public behaviours during mass decontamination. Third, to outline some specific recommendations for optimising the way in which incidents involving mass decontamination are managed.

Why It Is Important to Understand Public Behaviour

Incidents involving CBRN agents are likely to be very frightening for members of the public, because they are unfamiliar and ambiguous (e.g. [15, 18, 41]). People will also probably be unfamiliar with the decontamination process, and it is possible that decontamination could be more stressful for the people affected than the CBRN incident itself [34]. This is especially likely in incidents where decontamination is not managed effectively [5].

Until recently, planning for incidents involving mass decontamination has focused on technical aspects, such as developing and testing decontamination equipment, and there hasn’t been much consideration of likely public experiences and behaviour during the decontamination process (e.g. [5, 12]). Where likely public behaviour has been considered, there is often a reliance on common myths about disasters, such as public disorder or mass panic. However, over 50 years of research has shown that panic occurs very rarely (if at all) during mass emergencies and disasters, and that people are much more likely to behave in a helpful and cooperative way (e.g. [1, 2, 16, 17, 20–24, 35, 36, 40]).

The reliance on common myths about disasters can lead to a focus on the need to impose control on the actions of members of the public, with a perception that imposing such control will prevent people from ‘panicking’ and behaving in a disorderly way (e.g. [3, 25]). These types of control management strategies can involve withholding information from members of the public (e.g. [27, 30, 31]), and failure to respect the needs of the public (e.g. [5, 32]). This reliance on control management strategies is concerning, because research shows that these types of control management strategies may create public disorder, rather than preventing it (e.g. [26, 42, 44, 47]). The reason for this is that members of the public may see attempts to control or coerce them as illegitimate action on the part of emergency responders. This perception that responders are behaving in an illegitimate way may result in members of the public uniting to challenge the authority of emergency responders , thus creating the very disorder that emergency responders were hoping to prevent (e.g. [43, 45, 47]).

In addition to having the potential to create public disorder, withholding information from members of the public will make it difficult for them to undergo decontamination (even if they are willing to). As noted above, during incidents involving decontamination, there will likely be a relatively small number of responders, compared to members of the public. Because of this, members of the public will need to take action to help themselves: this will not be possible if they are not given information about the actions they need to take [9].

There is therefore a need to update planning and guidance for mass decontamination , to make sure that these are based on relevant theory and research about public behaviour, and not on outdated assumptions about mass panic. We have carried out extensive research to understand how members of the public are likely to experience mass decontamination, and how the way in which responders manage an incident involving mass decontamination will affect the way in which members of the public respond. Our research has been used to inform guidance and training for emergency responders and policy makers in planning for and managing mass decontamination, and the key findings are described below.

How Effective Management Can Promote Improved Decontamination Outcomes

In terms of promoting positive public behaviours in mass casualty decontamination, an effective management strategy will achieve five key things: (1) it will get people to agree to undergo decontamination; (2) it will help people to undergo decontamination quickly and efficiently; (3) it will encourage people to cooperate with each other during decontamination; (4) it will make people feel less anxious; and (5) it will ensure that those with greater functional needs are able to undergo decontamination. In order to understand how effective management can improve decontamination outcomes, a number of research studies have been carried out. These include a review of real-life small-scale incidents involving decontamination [5], a review of the literature relating to decontamination of members of vulnerable groups [12], focus groups with members of the public [13, 14], analysis of data from mass decontamination field exercises [6, 7], and mass decontamination online and field experiments [9, 10]. Each of these outcomes is described in further detail below, alongside relevant research.

Getting People to Agree to Undergo Decontamination

Getting people to agree to undergo decontamination will be crucial to the success of the decontamination process. For decontamination to be successful, people will need to agree to undertake any actions recommended by emergency responders. These actions may include disrobing, undergoing improvised and/or interim decontamination, and undergoing a decontamination shower in a specialist mass decontamination unit.

As mentioned above, decontamination may be frightening and embarrassing for members of the public, and this may make them reluctant to agree to undergo decontamination (e.g. [32, 50, 51]). A review of small-scale decontamination incidents showed that refusal to undergo decontamination was common [5]. This was especially the case during incidents in which people felt that they had not received sufficient information from emergency responders about the decontamination process, and when they felt that their needs for privacy and modesty had not been respected. Any reluctance of people to undergo decontamination will delay decontamination, and could potentially cost lives (e.g. [28]). It is therefore essential that people agree to undergo decontamination, and that they do so in a quick and efficient way.

Emergency responders can encourage people to agree to undergo decontamination by doing two key things. First, emergency responders should explain to members of the public why it is necessary for them to undergo decontamination. If people don’t understand why decontamination is important they are unlikely to agree to do it. Explanations should be health-focused where possible, should explain how undergoing decontamination will reduce the risk of further harm from the contaminant and will also potentially prevent secondary contamination of other people and places [9, 11]. Second, by showing respect for public needs for privacy. If people don’t feel that their needs for privacy and modesty have been met, they are unlikely to agree to undergo decontamination. While it may not always be possible to provide people with the level of privacy they would like, it is important to communicate why this is the case, and therefore demonstrate an understanding of and respect for public needs [11].

Doing these two things will demonstrate that responders are managing the incident in a legitimate way and will promote trust in emergency responders and the information that they provide. A key finding from our research into public behaviour during mass decontamination is that a perception that responders are managing an incident in a legitimate way is crucial for getting people to agree to undergo decontamination. When people feel that they have received effective communication, and that their needs for privacy have been met, this results in increased perceived legitimacy of emergency responders and the actions that they are taking. This is crucial, because this perception of responder legitimacy facilitates the formation of shared identity between members of the public and emergency responders which, as noted above, enhances cooperation with other group members and encourages people to act in accordance with group norms (e.g. the norm of undergoing decontamination). Shared identity between members of the public and emergency responders therefore encourages people to agree to undergo decontamination [11].

Helping People to Undergo Decontamination Quickly and Efficiently

As the section above demonstrates, getting people to agree to undergo decontamination is a crucial first step in ensuring that decontamination is successful. The next step is to make sure that people know what they need to do, to help them to undergo decontamination quickly and efficiently. The key to quick and efficient decontamination is to provide people with sufficient practical information about the actions that they need to take. Findings from decontamination field exercises show that people consistently report that they have not received practical information about what to do during the decontamination process, and consequently, that they are confused and don’t know what actions to take [6, 7].

To understand more about the effect of different levels of information on public behaviour during mass decontamination, we carried out a mass decontamination field experiment. During this experiment, three different groups of participants were provided with different levels of information before they underwent decontamination. Information included explanations about the importance of decontamination, updates about actions responders were taking, and practical information about the actions that participants needed to take during the decontamination process [9]. Participants were timed going through decontamination to enable a comparison of decontamination efficiency between groups. The optimum time for participants to complete the entire decontamination process was 9 minutes and 30 seconds. Findings showed that those who were provided with the most detailed information went through the decontamination process more quickly and efficiently than those who were provided with less detailed information, and in closest to the optimum time. In fact, of those who received the less detailed information, the slowest participants took 19 minutes and 48 seconds to undergo the full decontamination process; this is almost twice as long as the process should have taken.

This therefore illustrates how important it is for emergency responders to provide people with detailed information about the actions people need to take during decontamination, and not to assume that people will know what actions they need to take. It has sometimes been suggested by emergency responders and policy makers that during decontamination there will not be time to provide people with information, and that doing so will delay the decontamination process. The findings presented here show that the opposite is true: the more information that people can be provided with about what to do during decontamination , the more quick and efficient the process is likely to be.

Encouraging People to Cooperate with Each Other During Decontamination

As well as being willing and able to undergo decontamination quickly and efficiently, those involved will also need to cooperate with each other to make sure that the decontamination process runs smoothly. Cooperating with each other in the context of decontamination involves two different aspects: