A Concept of Air Quality Mitigation through the Planned Behavior of University Students Towards Sustainable Campuses

1.1 Impact of Air Quality at the Campus Level

At a college campus, air quality plays an outsized role in the physical health and cognitive performance of students or faculty. The deterioration of air quality, characterized by high-level aerosols in particulate matter (PM), nitrogen dioxide, and volatile organic compounds, gives rise to respiratory complaints as well as cardiovascular diseases, leading to other health disorders, such as organ failure, that are conceptually related to a poor indoor environment (Brugha & Grigg, 2014). Indoor air pollution can be a big deal for students, who spend much of their time inside classrooms and dorms. Exposure to indoor air pollutants can impair cognitive function, decrease attention spans, and harm schoolwork (Zhang et al., 2017). Poor air quality does more than just lead to health effects; it can also degrade the campus environment in other ways reducing comfort for all occupants, impacting potential students’ decisions concerning which colleges/universities to attend, and employees choose their employment locations (MacNaughton et al., 2017). As such, universities have a financial incentive to provide high air quality standards for the well-being and productivity of their community.

1.2 Campus Air Quality Guidelines

The NAAQS (National Ambient Air Quality Standards) sets limits on particulate matter, a major air pollutant in urban areas. Campuses should monitor and maintain PM levels within the following limits. PM 10 (annual range: 60 μg/m³, 24-hour average: 100 μg/m³), PM 2.5 (annual average: 40 μg/m³, 24-hour average: 60 μg/m³), and AQI (good 0--50, satisfactory 51--100). Regular monitoring of PM levels is essential, especially in areas with heavy vehicular traffic or ongoing construction (Central Pollution Control Board, 2009). With restricted vehicular access, the use of electric vehicles can help maintain standard and efficient air quality.

1.3 Objectives of the research

2.1 Attitudes toward the behavior

Attitude is the extent to which an individual expresses a favorable or unfavorable evaluation of behavior. Concerning air quality and its mitigation, attitude comprises beliefs about the necessity of taking measures against lower levels of pollution, expected advantages that result from carrying out those actions, or costs associated with execution. Increased knowledge of the effect of air quality on health and the environmental benefits of pollution reduction will likely lead to more inclined behavior toward participating in activities to reduce exposure environmentally (Bamberg & Schmidt, 2003; Steg & Vlek, 2009). For example, learning about how reducing vehicle use can reduce carbon emissions could increase attitudes toward public transport or cycling. Whether people believe that their actions will be effective in reducing air pollution is likely to influence which behaviors they choose (or are willing) to adopt to achieve better air quality. This is key in driving behaviors toward engaging in broader campus sustainability efforts or reducing electricity usage.

2.2 Subjective norms

These are the subjective feelings of social pressure to perform or not perform a behavior. These norms arise from the expectations of other parties, such as peers, family, or society at large, and profoundly affect individuals’ intentions to engage in air quality mitigation actions. At universities, the behavior, and the attitudes of peers can easily persuade an individual to act differently. This is done in part because when students believe that their peers respect and engage in pro-environmental behaviors, they are more likely to mimic those actions (Bamberg & Möser, 2007). In such cases, a culture of cycling or carpooling might develop among students. Universities that promote policies and campaigns focused on improving air quality contribute to developing a normative context for the sustainable promotion of behaviors. Examples include policies such as rewarding the use of public transport or car bans on campuses, which help strengthen the subjective norm that driving less is an important collective responsibility (Cotton et al., 2016).

2.3 Perceived behavioral control

This refers to the perceived ease or difficulty with which people believe they can perform a behavior and is assumed here to influence an individual’s confidence in their ability to successfully execute that behavior. It is strongly influenced by available resources, opportunities, and perceived barriers. The availability of public transportation services, recycling options, or energy-efficient appliances can lead to greater perceived control over behavior and facilitate engagement in air quality mitigation behaviors (Ajzen, 1991). By providing EV charging points and bike-sharing schemes at universities, students are encouraged to perform more work on their carbon footprint. Self-efficacy, or the perceived ability to perform an act, has a strong effect on perceived behavioral control. Specifically, behavior intention is affected by individuals’ self-efficacy beliefs for performing behaviors that help the environment (e.g., reducing energy use and planting trees). Identifying and addressing barriers to air quality mitigation behaviors, such as a lack of infrastructure, time constraints, or financial costs, is essential. Institutional support can help in overcoming these barriers and can increase the perceived behavioral control leading to a behavior change (Gifford, 2011).

3.1 Selection of databases and literature search

A thorough and objective search should support the SLR process by identifying pertinent research. It is necessary to find and use a database selection that guarantees thorough research coverage. In this sense, Scopus one of the most important platforms for article retrieval is used in this study along with the access of Google Scholar. This database provides comprehensive coverage of the literature and makes it possible to perform organized searches. First, prominent keywords associated with sustainable development, theory of planned behavior, and air quality were found. Next, several terms with relevant semantic meanings are combined. For this study, the final search string was as follows: [TITLE-ABS-KEY (“air quality” OR quality) AND TITLE-ABS-KEY (“theory of planned behavior” OR “pro-environmental”)]. A total of 42 articles from Scopus were identified via the search, and an additional 12 articles from Google Scholar were identified.

3.2 Screening of articles

The benchmark used in the SLR process to filter the article pool is provided by and comes from the screening of the articles. At this point, the articles were filtered based on the year, document type, source type, and language. [(LIMIT-TO (YEAR, “2010-present”) AND (LIMIT-TO (DOCTYPE, “ar”) AND (LIMIT-TO (SRCTYPE, “j”) AND (LIMIT-TO (LANGUAGE, “English”)) is the filtering operation that was used. The articles that were taken into consideration for this study could only be current ones (from 2010, in line with the theory of planned behavior and air quality). Only peer-reviewed articles were considered for the study in terms of document format and source type because they undergo a more thorough peer review procedure and offer more in-depth knowledge than other research articles, such as conference papers. Finally, items written in other languages were removed. During this phase, 41 articles from Scopus and Google Scholar were produced.

3.3 Eligibility and inclusion criteria of the articles

The articles from the previous phase were subjected to criteria such as abstract review, keyword analysis, appraisal of conclusions, and outcomes to determine which ones were eligible and appropriate for inclusion in this step. At this point, papers that focused on the theory of planned behavior at the city level and broad aspects of environmental concerns were eliminated. In the end, 24 articles a large quantity for critical content analysis were used in this study. Compared with other reviews of similar products, this sample size is favorable.

3.4 Meta-synthesis and critical content analysis of articles

After the quality check, 24 articles were selected for this review. These articles were reviewed and verified by the first and the second authors. Further, these articles were reviewed by the third author. Finally, the articles were analyzed and summarized. The first and the second author gathered information from the included studies. The data from the articles were extracted and evaluated by two authors independently. Further, it was reviewed by the third author.

In the SLR process, meta-synthesis is the analysis of the metadata included in the article pool. Extracting the metadata from each article enhances the SLR procedure and serves as a foundation for structuring the study’s framework. The metadata, which was organized tabularly, included details such as the name of the article, the year of publication, the research topic, and any restrictions. The phrase “idea thought matrix supplemented by components of analysis” accurately describes this extensive table. The articles were then further categorized into research themes, highlighting their similarities to create clusters out of the articles that were retrieved; this process is known as critical content analysis, and it helps to establish the current status quo and develop future trends in the field of study.

3.5 Results and findings

This research looked at 24 studies conducted by 103 authors in 24 countries. The average number of citations each article obtained was 18.33. There were 115 keywords. Table 1 presents that information in detail.

Figure 2 shows the country-wise article publications and how countries are interdependent in terms of citations. Since the larger nodes in the figure denote the number of occurrences, China has the highest number of publications. As some nodes in the figure are unclear in size to examine second and third places in publications, we created Table 2 via VOS viewer. It summarizes and ranks the countries with their articles. Accordingly, China, Taiwan, and Australia ranked first, second, and third, respectively, indicating that they are famous for their Theory of Planned Behavior concerning air quality.

Figure 2. Country-wise article publication.

3.6 Results of the studies

As shown in Table 3, the highest number of keyword occurrences was observed for the Theory of Planned Behavior. A larger green node is shown in Figure 3 to demonstrate it further. The empirical research was based only on the theory of planned behavior towards air pollution rather than expanding it to air quality, sustainable development, and mitigation structures.

Figure 3. Keyword co-occurrence network visualization.

The keyword co-occurrence network visualization in Figure 3 shows the connections of keywords shown in nodes. The connection represents the relationship between each keyword. Specifically, the strength of a relationship is characterized by the thickness of the line. Therefore, Figure 3 shows that the theory of planned behavior and humans are linked by a thicker line, indicating that the theory of planned behavior is directly related to humans and their perspective. Moreover, the links between air pollution and attitudes and between surveys and questionnaires indicate their relationships with the theory of planned behavior. The nodes in Figure 3 are in three clusters: red, green, and blue. Those clusters have keywords that are denoted in Table 4. As shown in Figure 3, the different clusters indicate that the theory of planned behavior varies across different areas of investigation.

3.7 Human health impact and behavioral response

This cluster focuses on the interactions between air pollution and human health, especially in susceptible groups such as children, and how these interactions influence behaviors linked to health. Using human trials, surveys, and questionnaires, among other methods, the cluster conducts empirical research to examine the presence and effects of air pollutants, especially particulate matter, on human health. To safeguard vulnerable populations, such as children, from the negative consequences of poor air quality, the cluster also explores how knowledge and awareness of these health implications affect behavior and decision-making. This cluster provides an approach to understanding the impact of air pollution and its quality on human health and behavior.

3.8 Perception and theory of planned behavior

This cluster delves into the interplay between air quality, environmental protection, and human behavior, guided by the theory of planned behavior (TPB). This study explores how perceptions of air quality influence environmental protection efforts and how the TPB can be applied to understand and predict behaviors aimed at mitigating air pollution. The cluster provides a comprehensive view of how individual behaviors, shaped by perceptions and theoretical frameworks, impact air quality and environmental protection efforts. By linking these concepts, the cluster aims to offer insights into the design of effective strategies to foster environmental stewardship and improve air quality through behavioral change.

3.9 Attitudinal influences on sustainable development

This cluster investigates air pollution, attitude, and sustainable development goals. The focus is on how the attitude towards air pollution can affect behavior and impact sustainable development. It also investigates policies that may affect sustainable development. By integrating insights from psychology, environmental science, and policy studies, it seeks to offer actionable strategies for improving air quality and advancing sustainability objectives.

3.10 Areas where empirical research is lacking - VOS viewer

This section covers the study’s second objective. The theories of planned behavior and air pollutants were the most used keywords in studies, as shown in Table 3, indicating that they have been extensively researched. The density visualization map created by the VOS viewer shows it in the node with a dark yellow background ( Figure 4). According to the VOS viewer manual, a node with a dark yellow background indicates sufficient research for establishing knowledge. However, keyword nodes with a green background indicate that there has been less research on those keywords. Thus, all other keywords in Figure 4 are in the green background, indicating insufficient research. Thus, there is a lack of research on air quality and sustainable development at the university level.

Figure 4. Keyword density visualization map.

3.11 Areas where empirical research is lacking – SLR

This analysis was conducted with a total of 24 articles. These articles were systematically reviewed and tabulated based on various criteria, including the title, keywords employed in the research paper, factors and sources contributing to the effects and causes, the methodology employed to achieve the desired outcomes, the results obtained, and the limitations of the study, which also outlined potential future research directions and questions. Among the 24 articles, at the university level, 11 articles were conducted within which China emerged as the main country with a focus research area on air pollution (An & Yu, 2018; Ramírez et al., 2023). The analysis helped in identifying a lack of research on the theory of planned behavior among students as well as in the Indian context (Sahu & Gurjar, 2020; Sundar et al., 2020).

The keywords within the papers focused on air pollution covering the aspects of fine particulate matter (PM 2.5), indoor and outdoor air quality, temperature, and emissions (Burdova et al., 2016; Can et al., 2015). Studies have examined indoor air quality in university environments, highlighting the presence of particulate matter and microbiological contaminants that impact students’ health and cognitive functions (Erlandson et al., 2019; Hayleeyesus & Manaye, 2014). The theory of planned behavior consists of health behavior, intentions, attitudes, behavior changes pro-environmental behavior, and other environmental concerns (De Groot & Steg, 2007; Greaves et al., 2013).

Sources and factors of air pollution and behavior changes were taken into consideration as they provide an area for further exploration and study about air quality because of its direct and indirect impacts (Bhat et al., 2022; Pereira et al., 2019). Sustainability was the least researched topic that can provide a platform for future focus areas (Sundar et al., 2020). University-level research was the main area for concern and needs to be more focused on due to the rapid and spontaneous behavioral changes of students and youth towards environmental concerns such as air quality which helps in designing and implementing sustainable practices and air quality mitigation strategies (Mateer et al., 2022; Niankara & Zoungrana, 2018). Previous studies have shown that students’ environmental awareness and optimism are shaped by their interest in the biosphere, indicating that educational interventions could significantly impact their behavioral intentions toward air quality improvement (Niankara & Zoungrana, 2018).

The methodology used in the studies helped the researchers in identifying the research gap, considering the sample size, and the technique of cluster and stratified random sampling was implemented and emphasized (Woo et al., 2022; Xu et al., 2021). Few research papers have developed questionnaires for assessing the intentions, attitudes, subjective norms, and perceived control behavior of the selected population regarding environmental concerns and air quality (Yang et al., 2020). The analysis of the methodology of the papers was important in the development of a conceptual framework, providing empirical data collection methods and analysis techniques for efficient results (Yuriev et al., 2020). Research has also explored how media exposure influences pro-environmental behavioral intentions, suggesting that communication strategies could enhance students’ engagement in air quality mitigation efforts (Yang et al., 2020).

The limitations of this study include common areas of concern, such as the longevity of the research, the application of the TPB framework at the university level for sustainable development, and the interrelationship between indoor and outdoor air quality and pollution (McCright & Dunlap, 2013; Steg & Vlek, 2009). Studies have demonstrated that environmental behavior is influenced by general beliefs and perceived barriers, which must be addressed to promote sustainable actions (Kollmuss & Agyeman, 2002). The literature review of the identified articles, conducted in a systematic literature review meta-synthesis format, aided in understanding and identifying research gaps or areas of least research content, including universities, sustainability, air quality, and its mitigation, as well as the importance of the Theory of Planned Behavior (Gifford, 2011; Cotton et al., 2016). Furthermore, governmental policies and building regulations have been examined for their role in improving indoor air quality and environmental sustainability within educational institutions (Ministry of Environment, Forest and Climate Change, 2016).

4.1 Attitudes toward the behavior

An individual’s attitudes toward the behavior are made by perceptions of how to engage in a specific action and its consequences. For example, the use of public transport may decrease the carbon footprint, and biking on college campuses can increase health. These beliefs, in turn, impact the valuations of outcomes and the degree to which an individual perceives these outcomes as advantageous or disadvantageous. The higher the value one places on outcomes such as the benefits of reduced pollution or better health, the more favorably one should see these behaviors. Therefore, a person will decide whether to use public transport or bike as an important solution in their choices based on the extent of weight they attribute to environmental sustainability and personal well-being attitudes as part of his/her decision balance.

4.2. Subjective norms

Normative beliefs are the second determinant of behavior in the Theory of Planned Behavior and are related to whether other people important to you tend to approve or disapprove of your performance of a particular act. These pressures are usually from significant social groups such as peers, family, or the culture on campus. For example, a student may report that they believe that their friends expect them to cut back while driving to reduce campus emissions. Through having this sense of pressure, individuals are motivated to comply (how much an individual is willing to conform to others). Motivation is typically fuelled here by a need to fit in and maintain their status among peers. Accordingly, by affecting behavioral intentions through social expectation pressures, normative beliefs are important determinants.

4.3 Perceived behavioral control

According to the theory of planned behavior, perceived behavioral control (PBC) refers to individuals’ belief in their ability to control petty actions facilitated or impeded by a given set of factors. Perceived control beliefs are standards based on what a person thinks about the difficulty or ease of carrying out definite actions. Insights are also affected by outside circumstances that cause an individual to feel simple to perform, such as facile driving accessibility because there is a free shuttle service. Perceived power refers to your confidence that you can overcome obstacles, such as biking in the rain because you have all the necessary gear for doing so. Control beliefs, as well as perceived power, and thus the extent to which one believes her or himself able, are two significant determinants of an individual’s capability belief leading to behavioral intentions influencing action.

4.4 Environmental and contextual factors

These are external influences on behavior, either enabling or preventing it. Facilities such as bike lanes, electric vehicle charging stations, and public transportation networks are available. Providing access to information about air quality levels and pollution reduction strategies. The rules or incentives provided by the campus administration, such as free bus passes for students, carpooling incentives, or penalties for excessive car usage, should be followed. Implementation of design strategies such as pedestrian-friendly zones, green spaces access to public transport, and installation of real-time air quality monitoring and reporting station and display. Effective implementation of environmental frameworks such as clean air initiatives, tree plantations, and guidelines can increase awareness and influence behavior.

4.5 Behavioural intentions

The intentions of an individual depend upon the three factors of TPB i.e. attitudes, subjective norms, and perceived behavioral control. Assessment of an individual action is referred to as attitude. Influence by peers or others, or social pressure and engagement affecting behavioral change is a subjective norm. The capacity of an individual to perform the act is referred to as perceived behavior control. The intention strength degree depends on the assessment of these factors that need to be well defined with great intent for behavior change and execution.

4.6 Actual behavior

To address air quality problems and environmental effects through performing various activities is termed as actual behavior. The decision or act such as walking, biking, and use of public transportation instead of driving alone to reduce vehicular emission. Implementing energy-saving practices such as turning off lights when not in use. By performing these activities, one can reduce their carbon footprint and mitigate air pollution. One can achieve sustainability and air quality improvement with these activities. Understanding and support to perform these activities can develop and promote efficient environmental policies.

4.7 Feedback loops

Feedback changes future behavior by changing the idea and perception of performing one activity. Behavioral and social feedback are two main categories of feedback. The result of how the activities affect the air quality and then changing the behavior to improve or reduce the second result is behavioral feedback. For example, one may decide to drive less in the future if they observe that it may lead to cleaner air. Social feedback is imitating the social or peer behavior. Social standards and peer pressure may encourage one to implement eco-friendly behaviors.

4.8 Outcomes

Air quality mitigation behaviors have short-term and long-term impacts. The short-term impact is a decrease in the emissions which improves air quality. This may immediately improve the quality of life of an individual and a community. Long-term effects are more consistent and impactful. Improved air quality leads to major health benefits, reducing cardiovascular and respiratory problems. Implementation of eco-friendly practices promotes sustainability. The worldwide effort to reduce climate change and promote a healthier planet for future generations this change is required for greater influence.