English

The means for keeping the indoor relative humidity (RH) and pollutant concentration below a threshold level of interests are necessary and essential to improving building performance in terms of indoor air quality (IAQ), energy performance and durability of building materials. In this paper, the similarity between the moisture and VOC (Volatile Organic Compounds) transport models is applied to study the effect of toluene (a typical VOC) and moisture buffering capacities of a hemp concrete wall on indoor toluene concentration and RH.

New types of low-cost sensors have the potential to replace existing sensor networks in buildings, which have high cost and low flexibility in terms of monitoring local indoor environmental quality (IEQ) close to the occupants. The objective of this study is to (i) investigate the reliability, accuracy, robustness, and communication capabilities of low-cost sensor networks and (ii) develop and implement an overall framework of monitoring and control of indoor environmental conditions, embedded in existing control infrastructures or using new system typologies.

The fan pressurization method that is widely used to measure the airtightness of buildings is known to have quite large measurement error. It is made up of random measurement error (precision) and systematic measurement error (bias).

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.