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An indoor office space should not only provide adequate illuminance on horizontal planes but also cater to the physiological and psychological requirements of the occupants. This paper aims to describe a lighting simulation-based work conducted in Kolkata, India which modeled an indoor office to investigate the effects of variation in room surface reflectance combinations on user perception, mean room surface exitance (MRSE), average horizontal illuminance and overall uniformity of horizontal illuminance.

A fluorescent illumination system–based office space was modeled and retrofitted with tubular LED lamps in DIALux. Simulations were conducted for 16 different room surface reflectance combinations and a five-point Likert scale-type survey questionnaire was formulated to conduct a survey with 32 test subjects to assess the subjective preferability of each resultant light scene.

Simulation results demonstrate that the relationship between average horizontal illuminance and MRSE as well as between average horizontal illuminance and overall uniformity of horizontal illuminance, was statistically significant (p < 0.001). In the conducted survey, the resultant light scene arising out of the reflectance combination of wall:ceiling:floor = 60%:90%:20% was the most well-received one with 187 convinced agreements (“agree” and “strongly agree” responses).

This work found strong linear correlation between average horizontal illuminance and MRSE and between average horizontal illuminance and overall uniformity. A five-point Likert scale-type survey questionnaire with seven questions was formulated and validated with 32 test subjects (Cronbach’s alpha > 0.9295), which showed that the wall:ceiling:floor reflectance combination of 60%:90%:20% was the most favored choice.

Good illumination creates an aesthetic environment that may positively influence patients’ well-being and provide comfort to the hospital staff. This study aims to focus on exploring the energy efficiency of lighting and subjective perception of the lit environment in a hospital ward to assess quality indicators of ambient lighting conditions.

The existing conventional tubular fluorescent lamp–based lighting system in the surveyed patients’ ward was retrofitted with light-emitting diode (LED) luminaires to explore illumination and energy parameters. Thereafter, a software lighting model was created, simulated and analyzed. A Web-based survey with five bipolar adjective pairs in a semantic differential scale was conducted with 48 participants to record and analyze their subjective responses pertaining to the variations in lamp types and surface reflectance combinations.

The findings imply that the LED tubular lamp–based illumination was deemed more adequate compared to other lamp types and the effects of variations in room surface reflectance combinations on the participants’ responses were statistically significant at α = 0.05 level. The simulated horizontal work plane average illuminance level varied from 131 to 171 lx, mean room surface exitance (MRSE) levels remained between 30 and 90 lm/m² and overall uniformity of illuminance remained between 0.5 and 0.7.

In a hospital ward illuminated by LED tubular lamps, variations in room surface reflectance combinations for a constant luminous flux package output from the lamps may affect the subjective perception of users and the correlation between horizontal work plane average illuminance and MRSE is found to be highly linear (coefficient of determination > 0.97).

This paper aims to raise awareness on how a simple action by the occupant can significantly influence building energy efficiency, cost and CO₂ emissions to the environment. Classrooms in schools are the primary energy consumers (45.4%) due to the use of artificial lighting, despite Malaysia's tropical climate being ideal for daylight exploitation. This paper focuses on assessing the workplane daylight distribution quality and quantity in baseline and existing conditions of a typical pre-school classroom in Kuala Lumpur as a model-based exploration strategy towards nearly Zero Energy Buildings.

The adopted method is based on the calculation of average daylight factor (DF), daylight illuminance level (IL) and uniformity ratio (UR) parameters affected by the internal fixed drapes through computational and in situ measurements according to the requirements of the law and respective standards comprising the MS1525:2019, GBI and BREEAM.

The results show how user behaviour can turn a well-daylit area (Net Lettable Area>90%) into a poor-daylit area (NLA<5%) by sacrificing natural daylight. All the parameters' values were significantly decreased from 10% (UR) up to 88% (ADF). Full dependency on artificial lighting has imposed a total of RM18858.90 and CO₂ emissions of 25,362 kg for all pre-schools' classrooms in the country per day.

The paper develops the occupants' awareness on their contribution to climate change and global warming through the information and transparency provided.

The evidence indicates that a simple action by the occupant can significantly influence visual comfort, EE, cost and CO₂ emissions to the environment.

The Purpose of this paper is to identify statistical relationships between visual environment and occupant productivity. Visual environment is one of the most important indoor environmental quality (IEQ) parameters, and it directly impacts occupant productivity in offices. The literature outlines the significance of the impact. Still, there is a lack of investigation, statistical analysis and inter-relationships between the independent variables (IEQ factors), especially in the hot and arid climate.

This study presents a research study investigating the effects and shows statistical relationships between IEQ on occupant comfort and productivity. The study was conducted in the Middle East, and data was collected for 12 months. It used the response surface analysis to perform analysis.

This study outlined seven unique relationships highlighting the recommended range, inter-dependencies. Results include that illumination has maximum effect on visual comfort and temperature, daylight having direct influence and relative humidity, wall type next to the seat and kind of workspace also impact visual comfort and productivity. These findings would help to improve occupant comfort and productivity in office buildings. It is recommended to include results and recommendations on design guidelines for office buildings.

This study presents the unique effects of non-visual IEQ parameters on visual comfort and productivity. This investigation also provides a unique method to develop the statistical relationship between various indoor environmental factors and productivity in different contexts and buildings.

Describes the rapid technical development that took place in the lighting industry in the 1980s, driven by energy cost pressures. Discusses product development, office lighting problems, legislation, changing working needs, new design approaches, HF fluorescent lighting, maintenance, and energy and lighting. Concludes that both economic pressures and users′ demand for better quality lighting are dictating a more professional approach to lighting scheme design.

University students spend a considerable amount of time in dorm rooms, where their environmental condition affects residents' health, well-being, sleep quality and the associated performance. Accordingly, this study aims to run an initial assessment of the environmental quality of two dormitory buildings in Tehran, using field studies and computational simulation, and then provide feasible optimized improvement strategies. The possible correlation between architectural elements and the environmental quality and the impact of proposed solutions on the annual energy use of these spaces are also discussed.

Field studies and computational simulation.

Results indicate that applied strategies, including shadings, reflectors, thermal and acoustic insulations, inlet vents and ceiling fans, can boost different aspects of the thermal condition, ventilation, acoustics and visual comfort by 21.77, 55.96, 20.69 and 50.37%, respectively. Accordingly, an acceptable comfort level can simply be achieved at a low cost by installing or replacing a few construction elements in dorm rooms. Nevertheless, a systematic architectural design can offer healthy spaces. For instance, south-facing rooms with large windows provide a higher level of thermal comfort and daylight quality.

This study shows that an acceptable level of IEQ can be achieved in dorm rooms by applying simple retrofit strategies. Moreover, energy consumption of dormitories can be significantly reduced using these solutions. However, the efficiency of the strategies in comparison to their economic aspects should be discussed, and results need to be further validated in real conditions. It is also recommended that a more extensive range of dormitory room typologies be studied in future studies. The results of this study are limited to the study context and so they can only be applied in case studies with similar use and climatic condition.

While many studies have explored the environmental quality of dormitories in different climatic conditions, no significant work has been found in Iran, Tehran investigating feasible optimized improvement strategies responding to all IEQ aspects of acoustics, thermal comfort, air and visual quality. Accordingly, this study makes an initial assessment of IEQ factors in a typical dormitory complex, and then develops practical retrofit strategies to bring the environmental condition of these spaces close to the suggested standards.

This paper aims to study employee mental health in relation to workplace design and indoor environmental quality (IEQ) when working from home, which has received little attention. The trend toward hybrid working urges for more knowledge.

Through a mixed data collection method, this study analyzed potential relationships (between mental health, workplace design and IEQ) from information obtained through a cross-sectional survey, repeated point-in-time surveys and desk-based IEQ sensors at home. Data were collected in April 2020 during a national COVID-19 lockdown in The Netherlands amongst 36 subjects. They all worked full time from home in this period and together completed 321 point-in-time surveys. The three data sets were combined and analyzed using bivariate and path analysis.

Outcomes indicate that subjective and objective IEQ conditions, workplace suitability and distraction affect employee mental health in the home workplace in a similar way as in the office. Being satisfied with the noise level increases concentration, self-reported well-being and engagement. High sound pressure levels (>58 dB) increased tension or nervous feelings.

To the best of the authors’ knowledge, this study is one of the first to explore employee mental health in relation to simultaneously assessed (perceived and measured) multiple IEQ parameters in the home workplace.

Examines lighting applications, both artificial and daylight, vis‐à‐vis the environmental aspect of buildings. Discusses lighting generally from the point of view of functional requirements, energy efficiency, and psychological and health effects. Concludes that light is an important factor in the wellbeing of building occupants and lack of it can have a deleterious effect on them. Therefore it is essential that light be made a prime consideration in building design.

The paper aims to investigate the comfort-related performances of an innovative solar shading solution based on a new composite patented material that consists of a cement-based matrix coupled with a stretchable three-dimensional textile. The paper’s aim is, through a performance-based generative design approach, to develop a high-performance static shading system able to guarantee adequate daylit spaces, a connection with the outdoors and a glare-free environment in the view of a holistic and occupant-centric daylight assessment.

The paper describes the design and simulation process of a complex static shading system for digital manufacturing purposes. Initially, the optical material properties were characterized to calibrate radiance-based simulations. The developed models were then implemented in a multi-objective genetic optimization algorithm to improve the shading geometries, and their performance was assessed and compared with traditional external louvres and overhangs.

The system developed demonstrates, for a reference office space located in Milan (Italy), the potential of increasing useful daylight illuminance by 35% with a reduced glare of up to 70%–80% while providing better uniformity and connection with the outdoors as a result of a topological optimization of the shape and position of the openings.

The paper presents the innovative nature of a new composite material that, coupled with the proposed performance-based optimization process, enables the fabrication of optimized shading/cladding surfaces with complex geometries whose formability does not require ad hoc formworks, making the process fast and economic.

The purpose of this study was to examine lighting systems at 77 laboratories located within one building to save energy and associated costs.

Field measurements of illumination were conducted and compared to lighting standards and industry recommendations.

For energy and cost saving, de-lamping all four-lamp luminaires down to two-lamp luminaires and installing occupancy sensors in all laboratories were recommended.

The research team’s project working hours and study period were limited. This study begins to fill the gap in the literature regarding lighting field studies.

By carefully considering light level recommendations, industry standards and installation budgets, existing facilities can install appropriate retrofits to save energy and money without sacrificing illumination levels. Recommended retrofits are anticipated to significantly curtail annual federal energy consumption practices at the labs.

The retrofits recommended in this study will reduce US federal government’s energy-related expenditures and greenhouse gas emissions in support of the 2010 Presidential Mandate. The proposed occupancy sensors are anticipated to compensate for humans’ failure to manually control lighting.

This field study adds value by documenting cost-effective methods to measure, record and manage laboratory lighting, and it calls for the implementation of social, economic and ecological interventions. The recommended retrofits will reduce US federal government’s energy-related expenditures and greenhouse gas emissions in support of the 2010 Presidential Mandate.