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Sleep is essential for multiple aspects of a person’s well-being and can be affected by a person’s physical and mental state in addition to the environment they sleep in. To date, the majority of research analyzing the relationship between a person’s sleep quality and indoor environment has focused on environmental parameters such as temperature, relative humidity, light, and noise. However, in recent years, a few key studies have identified indoor air quality (IAQ) as a potential contributor to sleep quality.

The University of Colorado Boulder (CU Boulder) is in Boulder, Colorado USA at 5280 feet above sea level. The campus has approximately 12 million square feet of infrastructure spanning over 100 years of building infrastructure evolution. In response to the COVID-19 pandemic, the University employed a science-based approach with campus researchers including aerosol scientists and campus epidemiologist and industry standards to inform a layered risk management strategy for an on-campus learning experience during the pandemic.

Worldwide concern has been focused on the airborne disease of the COVID-19 pandemic. This study investigated the effect of the limited space air stability on the mechanism of SARS-CoV-2 spreading in the interpersonal breathing microenvironment using an unsteady computational fluid dynamics (CFD) method. A validated numerical model was employed to simulate the transient SARS-CoV-2 releasing process from normal breathing activity. The computational domain was divided into an interpersonal breathing microenvironment and the rest macroenvironment.

In the current era, sensors in buildings have become an essential requirement for wide applications such as monitoring indoor air quality (IAQ), thermal and environmental conditions, controlling building heating, ventilation, and air-conditioning systems (HVAC). To accurately control the IAQ for all areas in the indoor space, it is necessary to obtain considerable data from different locations in the space for more precision.

Indoor air quality (IAQ) is influenced by several parameters and the sources of indoor air pollutants are numerous (building materials, occupant behavior, HVAC systems, Outdoor air, etc.). Utilization of low-cost sensor devices for screening the indoor air pollution has notably drawn interest over the recent years. These systems are easy to access, portable, need low maintenance, and can provide real-time and continuous screening of target contaminants.

Many recent studies have been reported that the novel coronavirus (SARS-CoV-2) can spread through an airborne transmission route. Although ventilation is generally adopted to control viral infection through airborne transmission, a high ventilation rate will increase the energy consumption of air conditioning. Under such condition, the portable HEPA-filter air purifier might be an effective supplementary measure. However, past discussions on its efficacy in reducing indoor infection risks are limited.

Ultraviolet germicidal irradiation (UVGI) inactivates viral aerosols in indoor environments. Upper room UVGI systems use wall or ceiling mounted fixtures to create a disinfection zone above the occupied zone. The performance of upper room UVGI systems varies with indoor airflow induced by mechanical ventilation and thermal plumes from occupants, which carries contaminated air into the disinfection zone where viral aerosols are partially inactivated before circulating back into the breathing zone.

Powerhouse Telemark is a low carbon plus energy project in Porsgrunn, Norway. The building is currently in a commissioning phase, but with most of the building under normal operation. The heating and cooling of the building is primarily done by a low temperature radiant floor heating system which is reversed in summer and used for high temperature cooling. The low temperature heating is provided by a geothermal heat pump and the high temperature cooling is provided by free cooling from the energy wells.

Our planet is rapidly urbanizing, leading to significant biodiversity loss. In architecture and urban planning, public and private developers are beginning to integrate vegetation into built environments such as green roofs, urban farms, and bioremediation systems, in some cases designed as novel additions to mechanical systems. In indoor environments, investigations into active biofilters for improving Indoor Air Quality have been investigated for several decades.

Air leakage in a rotary heat recovery device in air handling unit (AHU) was studied by a laboratory experiment. The experiment tested a commercial AHU with rotary heat recovery and equipped with various leakage control techniques, e.g. Automatic Leakage Control (ALCTM), rotor speed control (RSC) and purge sector, etc. In the test, exhaust air transfer ratio (EATR ) of the AHU was measured by tracer gas method at two levels of airflow rates in both constant airflow and constant pressure operation modes of the test AHU.