Effect of Exit Door Width on Flow Rate in Occupant-based Fire Evacuation Scenarios in Dormitories

Student dormitories are intensely used buildings that meet the resting, accommodation and living needs of students. It is necessary to ensure the safety of students and to eliminate possible risks in dormitories as intensive use areas. Fires pose a great risk in dormitories and may cause serious casualties and injuries. The reduction of casualties and injuries can be achieved by analyzing occupant behaviour during fires according to the building use scenarios. In this paper, a type of dormitory that provides two alternative exits is explored. The building use scenarios of the dormitory were investigated by making on-site observations. Students’ use of sleeping units, dining units and partial sleeping/dining units and fire exit routes were determined. Pathfinder computer program was used to analyze the fire evacuation performance. This program was defined in accordance with occupant behaviour and different fire evacuation times were suggested depending on the building use scenarios. At the end of the study, based on the evacuation times, the flow rate at the exit doors according to the location of the occupants was analyzed. In the fire escape routes, as the upper floors are reached from the lower floors, the occupant flow rate decreases at the exit doors and the flow rates continue to be stable as the number of occupants is saturated according to the door width. The decrease in the number of occupants in the dining unit decreases the flow rate at the exit doors. It is important that various assembly units in dormitories, such as the dining unit, are designed on floors that can directly provide evacuation to a safe area. The results obtained are suitable for all dormitories, residences, hotels and other similar buildings. Keywords: building use scenario, dormitory, evacuation, flow rate, exit widths

Effect of Climate Change and Occupant Behaviour on the Environmental Impact of the Heating and Cooling Systems of a Real Apartment. A Parametric Study through Life Cycle Assessment

Climate change has a strong influence on the energy consumption of buildings, affecting both the heating and cooling demand in the actual and future scenario. In this paper, a life cycle assessment (LCA) was performed to evaluate the influence of both the occupant behaviour and the climate change on the environmental impact of the heating and cooling systems of an apartment located in southern Italy. The analysis was conducted using IPCC GWP and ReCiPe indicators as well as the Ecoinvent database. The influence of occupant behaviour was included in the analysis considering different usage profiles during the operational phase, while the effect of climate change was considered by varying the weather file every thirty years. The adoption of the real usage profiles showed that the impact of the systems was highly influenced by the occupant behaviour. In particular, the environmental impact of the heating system appeared more influenced by the operation hours, while that of the cooling system was more affected by the natural ventilation schedules. Furthermore, the influence of climate change demonstrated that more attention has to be dedicated to the cooling demand that in the future years will play an ever-greater role in the energy consumption of buildings.

Optimizing occupant-centric building controls given stochastic occupant behaviour

Occupant-centric control (OCC) strategies represent a novel approach for indoor climate control in which occupancy patterns and occupant preferences are embedded within control sequences. They aim to improve both occupant comfort and energy efficiency by learning and predicting occupant behaviour, then optimizing building operations accordingly. Previous studies estimate that OCC can increase energy savings by up to 60% while improving occupant comfort. However, their performance is subjected to several factors, including uncertainty due to occupant behaviour, OCC configurational settings, as well as building design parameters. To this end, testing OCCs and adjusting their configurational settings are critical to ensure optimal performance. Furthermore, identifying building design alternatives that can optimize such performance given different occupant preferences is an important step that cannot be investigated during field implementations of OCC due to logistical constraints. This paper presents a framework to optimize OCC performance in a simulation environment, which entails coupling synthetic occupant behaviour models with OCCs that learn their preferences. The genetic algorithm for optimization is then used to identify the configurational settings and design parameters that minimize energy consumption under three different occupant scenarios. To demonstrate the proposed framework, three OCCs were implemented in the building simulation program, EnergyPlus, and executed through a Python package, EPPY to optimize OCC configurational settings and design parameters. Results revealed significant improvement of OCC performance under the identified optimal configurational settings and design parameters for each of the investigated occupant scenarios. This approach would improve OCC performance in actual buildings and avoid discomfort issues that arise during the initial implementation phases.

Virtual reality as a tool to investigate and predict occupant behaviour in the real world: the example of wayfinding

The use of virtual reality (VR) is expanding within the AEC sectors, commonly in design and pre-construction decision-making, including as a tool to test and predict the behaviours of building occupants. The implicit assumption is the experience of an immersive Virtual Reality Environment is representative of the Real Environment, and understanding this prior to construction reduces the likelihood and significance of design errors. However, there are very few studies that have validated this basic assumption, and even fewer that have made a direct comparison between Virtual and Real building use. One behaviour that influences design is wayfinding, and the acknowledged effect of familiarity with the layout of a building, which is the subject of this study. We produced an accurate immersive VR model of part of an existing University building and asked participating students to complete a wayfinding task in both the Real and VR buildings. The results show a quantitative improvement in the route and time taken to complete the task, but highlight differences in behaviours in each environment, including subtleties of head movement, a tendency to experiment and seek amusement, and a range of responses to the technology from enjoyment to suspicion. Further research is required to explore in more detail the effect of VR technologies on participants’ behaviour, and the limitations and potentials of VR as a decision-making tool beyond the example of wayfinding that we use. In conclusion, we need to adopt a cautious approach when designing by VR and recognise that the results of experiments such as ours should complement design decisions, rather than act as their sole justification.

The importance of understanding occupant behaviour in buildings: exploring the nexus of design, management, behaviour, and energy use in green, high-rise residential buildings

The quest to ‘green’ the built environment has been ongoing since the early 1970s and has intensified as the threat of exceeding 450 ppm of atmospheric carbon dioxide has become more real. As a result of this, many contemporary residential high-rise buildings are designed with hopes of achieving carbon emission reductions, while not sacrificing occupant satisfaction, or property value. Little is known about how the occupants of these buildings contribute to the energy and water consumed therein, nor the effects that these design aspirations have on occupant satisfaction. The present study relies on data collected in four recently built, Leadership in Energy and Environmental Design [LEED] certified, high-rise, residential buildings in Ontario, Canada. Using various sources of data (i.e., from energy and water submeters, questionnaire responses, interviews, and physical data relating to each suite) the extent to which physical, behavioural, and demographic variables explain suite-level energy and water consumption was explored. Energy use intensity differed by a factor of 7 between similar suites, electricity by a factor of 5, hot water by a factor of 13, cooling by a factor of 47, and heating by a factor of 67. Results show that physical building characteristics explain 43% of the heating variability, 16% of the cooling variability, and 40% of electricity variability, suggesting that the remainders could be a result of occupant behaviour and demographics. It was also discovered that 52% of respondents were not using their energy recovery ventilators [ERV] for the following reasons: acoustic dissatisfaction, difficulty with accessibility of filters, occupant knowledge and preferences, and a lack of engagement with training materials. Results suggest that abandoning mechanical ventilation in favour of passive ventilation could actually lead to greater satisfaction with indoor air quality and to decreased energy consumption. Using content analysis of questionnaire comments, the utility of contextual factors in understanding energy use and satisfaction in the study buildings, as well as their value in producing feedback for designers and managers, was explored. Combining quantitative and qualitative datasets was an effective approach to understanding energy use in this understudied building type.