The final sample of this scoping review consisted of twenty-one articles. Table 1 is a summary of the articles (see Table 1). Ten were based in the United States, six in Australia, two in Canada, and one in Italy. Two more articles included multiple countries in the studies. The results below are grouped into four sections related to communications materials, dissemination strategies, behavior change, and communications for vulnerable audiences—with a focus on gaps and recommendations. Table 2 contains detailed information extracted from the articles (see Table 2).
Communications materials and messaging findings and recommendations
Fifteen articles examined communications materials and messaging, and they offered recommendations including discussion of messaging content and design (5 articles), approaches to communications (2), use of a mobile application (3), use of real-life video footage (1), use of mapping for information distribution (2), effectiveness of risk communications (6), and communication gaps (2).
General messaging content and design
Five articles recommended messaging that uses simple, direct, clear, current, accurate, and specific language [33, 35, 38, 44, 55]. Authors commented that it is important that the communications are well-recalled, understood, and followed. This messaging should include information about fire locations, timeframes, safety, where to get additional updates and actions that people can take [33, 35]. Messages should also be timely, practical, consistent, and provide details about short-term and long-term health effects [38, 55]. Marfori et al. also noted that participants remembered short messages and gained knowledge but expressed interest in having added messages that were about both the short-term and long-term health risks of wildfire smoke [38].
Two articles provided more guidance for risk communications [36, 56]. Damon et al. called for ‘new’ materials to maintain public risk awareness year after year [56]. Messaging must be non-alarming and scientifically grounded. The public must be convinced of their self-efficacy to take recommended protective actions and must be notified to take actions against wildfire smoke exposure in a timely manner. Sugerman et al. discussed messaging that contains both non-technical actions, such as staying inside and closing windows, as well as technical actions, including use of home filtration devices or N95 masks [36]. They found that people’s non-technical recall, understanding, and compliance is high, but that technical messaging about High Efficiency Particulate Air (HEPA) filters and N-95 respirators should be better explained to the public.
Use of various media for communications
Three articles addressed the benefits and barriers of using the Smoke Sense mobile application, and assessed the knowledge gains from using the app [34, 49, 51]. Smoke Sense is a smartphone application, originally developed by the US EPA, that provides wildfire-related health risk resources and engages affected participants (“citizen scientists”) on wildfire smoke issues. Smoke Sense also shares information about daily air quality, maps of fire locations, and satellite images of smoke plumes [51]. In two different papers, Hano and their EPA colleagues concluded that it was a valuable app to provide general information about smoke risk for individuals, organizations, and communities, but that it needed improvement to provide population-specific information [34, 51]. Authors found that the Smoke Sense app can support organizations that can disseminate information about wildfire smoke, as well as support community efforts to protect sensitive and vulnerable groups [34, 49, 51].
From these qualitative and quantitative studies, recommendations for messaging included increasing individuals’ knowledge about smoke risks to protect themselves or their families, building self-efficacy for reducing exposure and actions to take, linking exposures to symptoms and cost-benefit relationships as well as information related to individuals’ personal concerns, and emphasizing the impact that reducing exposure may have on what individuals care about, e.g., maintaining good health and fitness [34, 51]. Furthermore, related to behavioral outcomes, an unblinded randomized controlled trial found that Smoke Sense app use among a specific vulnerable group – young adult participants with provider-diagnosed asthma – resulted in better asthma management during poor air quality days [49]. Postma et al. discussed the use of different features (e.g., peer message boards, daily spirometry readings, and air quality updates), which were integrated by technology partner Urbanova, within Smoke Sense, to increase engagement from participants and knowledge about smoke exposure/its effects on those with asthma [49].
One qualitative study found that showing real-life, vivid video footage of past wildfires could be a useful communication approach because it led to an increase in some desired behaviors, such as seeking knowledge, reducing exposure, finding more information about risk to home/area, and speaking with household and community members—actions linked to reducing exposure to wildfires and smoke [54].
Use of mapping for information dissemination
Studies by Stieb et al. and Cao et al. found that maps were effective for sharing information as well as increasing people’s knowledge about wildfire smoke and other environmental emergencies [37, 50]. Steib et al. researched the use of mapping health risks from natural hazard exposures (floods, wildfires, and contamination of air and water) as a risk communication technique and found that maps were better understood and interpreted than text [37]. The authors concluded that app and map developers should engage in an iterative process to design maps. Inclusion of visual cognitive science features (e.g., color, position, patterns, motion) and actionable information was important to adapt maps for effective risk communications. Cao et al. recommended a hybrid approach that combines maps with selected text message information [50]. Appropriately designed maps also better communicated wildfire and wildfire smoke warning information, improved comprehension, elevated risk perceptions, and increased appeal to the public. These maps were best complemented by textual descriptions of safe shelters, such as landmarks, names, and addresses.
Effectiveness of risk communications: Overall, as described above, eight articles [34, 36,37,38, 49,50,51, 54] in this category included assessments of effectiveness of risk communications for improving knowledge, behavior change, and health outcomes. Two articles noted that people effectively understood and recalled information from general messaging content and design [36, 38]. Six articles found that the use of various media, such as Smoke Sense app, video with real-life footage, and maps (especially maps that include text linked to spatial features), helped to improve knowledge, behavior change, and health outcomes [34, 37, 49,50,51, 54].
Gaps in communications
Two papers examined gaps in communications [60, 62]. Van Deventer et al. found wide variation in message content [62]. The most common personal interventions included reducing activity and staying inside during wildfire smoke events. However, regarding information specific to vulnerable populations, less than half of 85 government sources (47 social media-based messages, 38 digital articles from website) and 188 media messages (all digital articles from news sources’ websites) examined contained information about wildfire smoke. Approximately half contained a reference to a trusted source of information, but high-efficiency particulate air (HEPA) filtration was not mentioned at all. They concluded that government and news media would benefit from improved coordination of information about health risks of smoke exposure, approaches to reduce exposure, input from vulnerable populations, and risk communication tools, templates, and resources. Riden et al. discussed limitations in safety precautions for farmworkers during wildfire smoke, including the need for protective masks or respirators, air quality monitors, and changes to work schedules during events, and suggested that better resources are needed to assist employers and supervisors in complying with wildfire smoke safety regulations [60]. Agricultural employers varied in their knowledge and experience relative to responding to poor air quality caused by wildfire smoke.
Communication delivery strategies: dissemination methods, pathways, and recommendations
Eight articles discussed communication delivery strategies, including traditional and digital communication strategies (7 articles), and allocation of resources within agencies specifically designated for communication and outreach measures (1 article).
Traditional and digital communications
Eight articles outlined common communication channels [33, 35, 36, 38, 44, 52, 55, 56]; three of these articles were literature reviews [35, 44, 55].
Authors recommended communicating through a combination of channels: radio, television, internet, social media, social networks, hotlines, mass media, local papers, and phone to effectively deliver knowledge and encourage behavior change [33, 35, 36, 44, 55, 59]. Burns et al. found that respondents older than 40 years of age tended to receive risk communications through emergency services and city councils, radio and local papers, and from members of local organizations or government [33]. However, in 2009 and 2010, respondents under 40 years of age most commonly used television, local papers, friends, family, and neighbors. More recently in 2020, Keegan et al. stated that traditional sources like television have been the preferred method of communication delivery but that a preference for online and smartphone-based communication has emerged among younger, female, and urban populations [55]. Additionally, authors recommended locations for communications, such as post offices, road signs, schools, retirement facilities, childcare areas, presentations at public events, and billboards [33, 44, 59]. They commented that communication from healthcare workers, texts, and social networks may be effective, but require further research.
Authors provided recommendations on timing for communications delivery. The review by Keegan et al. concluded that messages should be delivered as early as possible to give people time to plan and act in the case of a smoke event [55]. Damon et al. discussed disseminating information in a timely and effective manner and using “message blanketing” at all local media outlets, in addition to statements from local opinion leaders and organizations [56].
Articles included findings regarding the knowledge gain and recall of communications about wildfire smoke. Mott et al. discussed people’s recall of several interventions including public service announcements (PSAs) after a wildfire event and commented that participants more frequently recalled PSAs distributed via radio and by physician/clinical personnel [52]. In a qualitative study done by Marfori et al., participants recalled delivery strategies including media releases, digital information and social media posts from public health and emergency services, and word of mouth [38]. Participants reported that social media was a source that provided more information about smoke than the information on wildfires that dominated the other news platforms. Participants also shared that it was difficult to know which sources to rely on and that they trusted official communications from governments more than those shared on social media from non-government sources. Social media was found to allow real-time dialogue between authorities and the public, and amplified messages.
Resource allocation for wildfire smoke communications
Olsen et al. suggested prioritizing fire and smoke-related communications within agencies by allocating agency resources specifically for staff training in communication and outreach endeavors, and for coordinating messages across and within agencies [59]. Authors found that taking advantage of existing resources including informal social networks among the public, and building long-term relationships both between agencies as well as with the public were viewed as effective in distributing communications to audiences [44, 55, 59]. Olsen et al. warned against inconsistent messaging from different agencies and inadequate reach of messages [59]. Their recommendations included aligning internal priorities when communicating and building relationships with the public, as well as evaluating communications delivery to the intended number of people.
Effectiveness of risk communications
Overall, five articles in this category included assessments of effectiveness of risk communications for improving knowledge gains, behavior change, and health outcomes. These articles discussed traditional and digital communications that were effective for successful and timely dissemination of risk communications [33, 44, 52, 55, 59].
Motivating behavior change: knowledge acquisition and trust building
Eleven articles discussed behavior change, including motivating public behavior change through community-level interventions (5 articles), increasing knowledge about wildfire smoke risk exposure among practitioners serving the public (3 articles), and examining public trust (3 articles). All eleven articles assessed behavior and behavior change (but not behavior intention) in the context of reducing wildfire smoke exposure.
Community-engaged interventions
Five articles described in-person intervention approaches associated with behavior change [34, 49, 52, 54, 57].
Authors of two articles discussed community-level interventions for Indigenous populations. In their qualitative study, Dodd et al. interviewed members of three Tribal Nations in Canada [57]. They found that community-based initiatives could reduce the impact of smoke exposure on physical, mental, and emotional well-being. These initiatives included removing flammable materials from around houses, joining community social support time at the community hall, and improving food security and connection to land-based activities (e.g., berry harvesting, fishing). Mott et al. conducted a retrospective study of Hoopa Tribe members affected by the 1999 wildfire in Humboldt County, California (USA) [52]. The study focused on recall of multiple community-focused interventions: effectiveness of free masks, free hotel services to shelter from the smoke area, high-efficiency particulate air (HEPA) air cleaners (distributed to individuals with pre-existing conditions), and PSAs [52]. PSAs were the most effective intervention. Mask use was associated with increased time outdoors and therefore increased exposure, but evacuation to hotels was not conducive to continuing employment as many residents worked in fire camps to fight forest fires. As a result of PSAs, the most common action taken was to stay indoors, rather than leave the area, use a mask, or use an air cleaner. Participants had highest recall of PSAs distributed via radio compared to all other sources, some of which included physicians, social networks, television, newspaper, and the Tribal Council. Additionally, those who recalled any of the PSAs were less likely to report worsening respiratory symptoms.
Hano et al., Hano et al., and Postma et al. indicated that the Smoke Sense application may support behavior change at multiple societal levels [34, 49, 51]. At the individual level, to protect health and increase awareness out of concern for health of self and family. At the organizational level, to advance organizational efforts in the area by using the app to distribute new tools and resources regarding smoke. At the community level, to increase awareness of connections between wildland fire, smoke, air quality, and health [34, 49].
In their case study, Chapple et al. found that study participants exhibited more protective behaviors and concerns for wildfire smoke after watching a video with real-life footage, compared to those who did not watch the video [54].
Knowledge among practitioners
Authors found that professionals with past experiences in wildfire-related work had significantly higher knowledge of wildfires/smoke exposure [53], had improved ability to make informed decisions in the face of an emergency [61], and better understood the current situation [61]. Spano et al. discussed that those with direct experience had, and also asked for, more information about these topics, indicating that practitioners/those experienced with wildfires can be an especially valuable source of knowledge for others [53]. Thomas et al. interviewed emergency risk communication professionals, who shared that working with the same group of people and stakeholders over long periods of time was helpful to the professionals to make informed, tailored decisions during smoke event emergencies [61]. Additionally, Errett et al. found that governmental agencies and academic organizations, participants at a state-wide wildfire smoke exposure symposium, proposed key research areas to increase the public’s knowledge of wildfire smoke risks [58]. They encouraged researchers and practitioners to study the following areas: smoke exposure, health risk, risk communications, behavior change and interventions, and legal and policy issues.
Public trust
Burns et al., Olsen et al., and Fish et al. all highlighted the necessity of trusted sources of information, the role of local agencies and governments, and the importance of communication sources [33, 44, 59]. Authors found that sources within the same social network influenced the value of fire and smoke messaging, and that neighbors and local residents were trusted sources of wildfire smoke communications [44, 59]. In three articles, authors discussed building public trust and improving message effectiveness through credible information sources [33], communication channels [44], and re-tweets or re-shares of social media posts between official accounts [35]. Examples of sources trusted by the public include authoritative local sources, the local police, as well as the Red Cross and State Departments of Health Services.
Effectiveness of risk communications
Overall, ten articles in this category included assessments of effectiveness of risk communications for improving knowledge, behavior change, and health outcomes. Five articles discussed community-engaged interventions that were associated with behavior change [34, 49, 52, 54, 57]. Two articles assessed ways to increase knowledge among practitioners and the public [53, 58]. Three articles suggested that effective communications included building public trust and using credible information sources [33, 44, 59].
Communications for vulnerable populations
Literature regarding risk communications for vulnerable populations to reduce wildfire smoke exposure was limited – only six articles were found. In general, authors found that communication resources for vulnerable populations were limited. For example, in Keegan et al., of twenty-six health protection messaging communications included in their study, only nine were relevant to vulnerable populations [55]. Specific resources relevant to pediatric populations were also found to be lacking [35].
Culturally and linguistically diverse groups, those with hearing, vision, and mobility-related disabilities, those living in high smoke-risk geographic locations, those with pre-existing chronic illnesses, those who are children or older adults, and those who are pregnant may benefit from targeted health recommendations about wildfire smoke exposure and resources on prevention/mitigation strategies [35]. Authors recommended prioritizing communications for communities that have greater exposure to smoke events [55], including actions to reduce wildfire smoke exposure instead of only updates about wildfire smoke situations [35], and providing communications to at-risk groups before the general population [44]. Mott et al. and Dodd et al. emphasized the importance of community-level initiatives for Indigenous populations in northwest Canada and in Hoopa Valley, California, to increase awareness and behavioral change [52, 57].
Postma et al. found that among young adults ages 18–26 with asthma diagnosed by healthcare providers, the Smoke Sense mobile application use was effective in increasing air quality awareness knowledge and improving asthma management [49]. Specifically, young adult participants thought that the version of Smoke Sense with Urbanova’s integrated features for mapping smoke areas, air quality advisories, spirometry graphs, weekly reminders, and peer message boards, was easy to use.
Effectiveness of risk communications: Postma et al. noted that use of the Smoke Sense mobile application and its integrated features was effective to increase knowledge about air quality and wildfire smoke and positive behaviors to manage asthma [49]. Other articles in this category did not assess effectiveness of risk communications for vulnerable populations.