Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:14
Monitoring and regulating the air quality inside critical infrastructure is essential for protecting occupants from external and internal airborne threats, such as pollutants, toxic chemicals, and pathogens. The outdoor air can be contaminated with agents such as diesel and car exhaust or with more toxic agents like Toxic Industrial Chemicals (TICs). In case of a pandemic, there is a threat of viruses and bacteria which can spread in the building. These airborne agents can penetrate and disperse inside the building via windows and doors or via the ventilation system.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:08
Most current building materials are industrially processed, resulting in increased carbon emissions. Global annual carbon emissions due to construction materials reached its peak in 2013, 9.5 gigatons of CO2 were produced. Upcoming circular economies can have a positive impact on the environment since reusing materials can lower carbon emissions. This economy encourages the use of more innovative materials (e.g., textile insulation, cellulose insulation, hemp, and cork) and recycling old materials.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:07
The quality of indoor air in buildings depends on many factors. Some of these factors have internal sources, and some have external sources. The internal loads of the room include those generated by people: CO2 and moisture emissions from breathing, heat emissions from room equipment: volitale organic compaunds VOC. External sources are, for example, particulate matter present in the air, which is the result of emissions from cars and the burning of fossil fuels. The scientific literature states that car traffic can contribute a large share.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:06
Nowadays, people spend most of their time indoors. Homes, offices, leisure and workplaces must meet people’s needs and provide safe, healthy and productive environments. The supply of fresh air plays an important role in achieving these goals. Not only by providing the right temperature and humidity but even more with the purity of the air inside the rooms. A recent study of the World Health Organization showed a significant correlation between yesterday’s particulate matters concentration in outdoor air and today’s death rate counting 7 million deaths in 2022 caused by air pollution.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:05
Open offices, where more than one person works, have been used frequently in recent years. However, there are many studies on the efficiency of the indoor air quality of the employees in these offices. It has also been shown that the risk of cross-contamination is higher in such offices during the COVID period, but this risk can be reduced by increasing the amount of fresh air.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:04
The main task of every ventilation system is to dilute and extract pollutants from indoor air, most importantly in occupied space. This is usually achieved by exchanging polluted indoor air with less polluted outdoor air. In the case of a mechanical ventilation system, this process requires a fan power to be provided which is approximately proportional to the power of three to the resulting airflow. Because of this, reducing the necessary airflow to be provided by the ventilation unit e.g., by 10% would lead to a reduced power supply of about 27%.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:03
Outdoor PM2.5 has a continuous and significant effect on the indoor environment, and lobby floors, in particular, can be exposed to high concentrations due to entrance doors and greater airflow rates than other floors. In this study, the PM2.5 indoor-to-outdoor (I/O) ratio for lobby floors was evaluated according to the operation type and configuration of entrance doors. Airflow analysis was conducted for an office building with multi-zone network simulation, and the I/O ratio was evaluated for different entrance strategies according to the occupant traffic schedule.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:02
Sleep is essential for overall health and well-being. The quality and efficiency of sleep are strongly influenced by the sleep environment, including indoor air quality. This study investigates the influence of mechanical ventilation on bedroom air quality during sleep and its impact on sleep efficiency and quality. Objective and subjective measurements were conducted to assess the effects of operating a mechanical ventilation system.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 15:01
The predicted and measured carbon dioxide (CO2) emitted by human respiration into an occupied space has been used as an indicator for controlling buildings' ventilation rates. However, this application assumes a constant emission rate for the entire population. Conversely, new knowledge has shown that this variable depends on the number of people in the room and their sex, diet, height, and above all, body mass and metabolic rate.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 14:59
The risen awareness of improved indoor air quality has resulted in an increased energy demand for HVAC systems due to higher air exchange rates and the additional operation of air purifiers. Therefore, the need for energy-efficient methods to improve indoor air quality has grown. In this experimental study, we develop an innovative wet scrubber concept to remove solid particles from the airflow. In contrast to conventional wet scrubbers, this concept uses a perforated plate and the hydrostatic pressure to feed water droplets into the air stream.