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.
Submitted by Maria.Kapsalaki on Wed, 03/06/2024 - 14:58
Maintaining a good indoor air quality level has received growing attention in the past years. Especially the smaller particles like PM2.5 (particles of aerodynamic diameter less than 2.5 μm) and UFP (ultrafine particles, aerodynamic diameter less than 100 nm) might lead to higher health risks. Vehicle cabin is one challenging environment due to the elevated particle concentrations from the surroundings.
Submitted by Maria.Kapsalaki on Tue, 03/05/2024 - 14:56
We performed residential indoor fine particle (PM2.5) measurement from 26 homes and three outdoor monitoring locations. Six PM2.5-bound phthalate easters (PAEs) — including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DnOP) — were measured using a thermal desorption-gas chromatography/mass spectrometer method. Average concentrations of summation of six PAEs (Σ6PAEs) in residential indoors (646.9 ng/m3) were slightly lower than the outdoor levels.
Submitted by Maria.Kapsalaki on Tue, 03/05/2024 - 14:55
The world is seeing a rapid increase of cooling of buildings1. This is driven by multiple factors, such as urbanization and densification, climate change and elevated comfort expectations together with economic growth in hot and densely populated regions of the world. Additionally, disruptive events, such as extreme heat and heat waves are occurring more often and are expected to become a common phenomenon by mid-century. The trend towards cooling seems inexorable. It is therefore mandatory to steer this development towards sustainable solutions.