The density, form, and dimensions of urban morphology are important for healthy living conditions in cities, especially if they are related to the climate and air pollution. Morphology and environmental conditions determine the relationship between open and built space, the width of street spaces, the aerodynamic characteristics of wind currents, albedo, and the retention of pollutants, as well as determining the radiative exchange with the atmosphere. Studies on the COVID-19 pandemic have focused on the assumption of a possible relationship between the spread of the SARS-CoV-2 virus and the presence and concentration of airborne particulate matter (PM₁₀ and PM_2.5). This paper focuses on the research of indoor air quality (IAQ) in two schools with naturally ventilated classrooms in Ljubljana, Slovenia. The presence of particulate matter (PM_2.5 and PM₁₀) and the concentration of CO₂ were studied, along with other microclimatic conditions, e.g., ambient temperature, relative humidity, air pressure, and wind conditions. These were compared and assessed via analysis of variance (ANOVA) and Duncan’s post hoc test. The main concern was to see how effective different ventilation strategies are, as well as how the openings in the classroom impact the concentrations of CO₂ relative to the concentrations of PM_2.5 and PM₁₀ particles as a side effect of these ventilation strategies. The inconsistent application of recommended COVID-19 ventilation strategies suggests that IAQ in naturally ventilated classrooms is highly determined by individual perceptions of indoor air quality. The results also suggest that the IAQ is significantly affected by the schools’ urban environment; however, this is not considered within the national COVID-19 ventilation recommendations. Future ventilation guidelines for pandemics should also include the urban environment as a risk factor for inadequate IAQ, instead of focusing solely on pathogen characteristics.

Parking in park-and-ride (P + R) facilities on the outskirts of a city reduces the traffic inside the cities and follows the principles of sustainable mobility. However, large paved (asphalt) surfaces create urban heat islands (UHI). This causes the temperature to rise in vehicles during full-day parking, which has a negative effect on comfort level and driving performance. This study was conceptualized as two-stage research. The first (preliminary) stage dealt with the measurement and analysis of temperature data at two nearby open parking lots in the city of Ljubljana, one of which was the main research spatial area, P + R Barje (L1), and Trnovo parking (L2), which was used for comparison in the first-stage research. In the preliminary research, we underlined the problem of long-term parking in parking areas exposed to heatwaves (HW). The second stage involved the studying of greening schemes in P + R facilities, which would allow for optimal shading during parking. Advanced 3D and 4D models using ENVI-met and LEONARDO software were developed, which assessed the parking surfaces and the areas of optimum outdoor comfort. Shading by greenery was adopted in this paper, as the strategy aimed at improving the conditions by modelling different variants of greening the parking lot L1.

Environmental modelling software can be useful for evaluating design interventions and formulating strategies to achieve a specific purpose, such as providing outdoor thermal comfort. It is less commonly used in predicting the dispersion of street pollutants. The aim of this research is to test selected morphological patterns with respect to their influence on wind conditions and the transport of traffic pollutants, and to verify the results against previous studies. The objective of the research is to evaluate relations between building typology in interactions with urban atmosphere. The method utilises a wind tunnel simulation with a static line source of emissions. Experiment results show that the exposed urban morphology models display an impact on flow conditions and consequently on the dispersion of traffic pollutants. At the same time, the results highlight the importance of urban aerodynamic perspective, particularly of urban spaces that can be expected to be subject to higher traffic pollutants in terms of urban air pollution.