indoor air quality

The overall objective of the IEA EBC Annex 68” Project, “Indoor Air Quality Design and Control in Low Energy Residential Buildings”, has been to develop the fundamental basis for optimal design and control strategies for good Indoor Air Quality (IAQ) in highly energy efficient residential buildings, and to disseminate this information for use in practice. The project was defined in 2015, the working phase lasted for the years 2016-19, and the project was concluded with publications on 2020.

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.

Urbanization has led to systemic environmental factors that degrade air quality and microbial diversity, negatively impacting human health and wellbeing. Conventional building Heating, Ventilation and Air Conditioning (HVAC) units that filter airborne pollutants and support Indoor Air Quality (IAQ), are often energy intensive, decrease indoor microbial diversity, and are still unable to address specific pollutants or seasonal psychrometric profiles.

A longitudinal study was conducted to establish metrics on perception, concentration and characterization of indoor air quality (IAQ) at a university library building. A questionnaire was applied to library staff in 2016 and 2017 to measure perceived indoor air quality (PIAQ) and perceived respiratory health impacts (PRHI). Measurements of PM2.5-10 and PM2.5 concentration levels were made in 2017 and 2019, respectively.

In the UK, people spend over 90% of a day indoors. On weekdays, when outdoor air pollution concentrations peak in the morning and in the late afternoon, people are usually either in non-domestic premises or on their way to/from non-domestic premises. Therefore, establishing the distributions of indoor air pollutant concentrations in non-domestic environments is essential to model human exposure to hazardous air pollution, especially for vulnerable populations, such as schoolchildren or patients in hospitals.

This paper reports preliminary analysis from a large field study of 100 university classrooms in Central Texas. Lecture classrooms and auditoriums were sampled for three consecutive weekdays in the 2019 – 2020 academic year. Carbon dioxide (CO2) concentrations, used as a marker for both ventilation and exposure, and temperature were measured in the general room area and when able, the supply airstream. HVAC control data that relates to ventilation was also saved for comparison.

Climate change is driving the construction sector to use of more environmentally friendly and sustainable materials. Hemp concrete has been recently adopted as an innovative solution by the building industry to reduce emissions, as this material stores more CO2 than the emitted during its production. Part of this storage occurs during its service life leading to a reduction of indoor CO2 levels. CO2 has been widely used as a proxy for evaluating indoor air quality (IAQ).