IAQ

The Book of Proceedings of the 44^th AIVC - 12^th TightVent - 10^th venticool  Conference "Retrofitting the Building Stock: Challenges and Opportunities for Indoor Environmental Quality", held in Dublin, Ireland on 9-10 October 2024.

The Presentations the 44^th AIVC - 12^th TightVent - 10^th venticool  Conference "Retrofitting the Building Stock: Challenges and Opportunities for Indoor Environmental Quality", held in Dublin, Ireland on 9-10 October 2024.

Following the pandemic of Covid-19, the scientific interest in ventilation rate of buildings, and especially in spaces with high occupancy, has increased. The creation of a healthy and acceptable internal environment, especially at workplaces is considered necessary, both to deal with the sick building syndrome, or the spread of various diseases, as well as to improve the comfort of employees.

The Performance 2 project (2020-2024) is a French national research project that aims to evaluate the long-term performance and durability of Humidity-based Demand Controlled Ventilation (DCV) systems installed in two multi-family social housing buildings, located in Paris and Villeurbanne, France.

This paper presents a comprehensive evaluation of Relative Humidity-Controlled Mechanical Extract Ventilation (RH-MEV) systems installed in multi-family social housing buildings, focusing on the assessment of in-situ aging and the impact of maintenance on the performance of the system. Building upon the Performance 2 project conducted from 2020 to 2024, which evaluated the durability and performance of RH-MEV systems over a 15-year period, this study delves deeper into the longevity and maintenance aspects of these systems.

Increasing attention is being paid to radon concentrations in the assessment of indoor climatic comfort. Radon is a naturally occurring radioactive element that, under unfavourable circumstances, accumulates in excess in a building. Elevated concentrations of it can adversely affect the health of building occupants, resulting in increased interest in this element.

During the COVID-19 pandemic, besides sanitising, masking, and increasing social distancing, opening classroom windows was the NZ Ministry of Education's main requirement for reopening schools. However, a pre-COVID-19 survey showed that only a third of the NZ teachers opened windows during teaching time. Achieving a suitable ventilation level could not rely on humans to open windows. Heating, Ventilation, and Air Conditioning (HVAC) systems are not affordable for most NZ schools.

This study focuses on the impact of filtration efficiency level and airflow control, based on CO2, on indoor air quality described by particle concentration in an urban low energy consumption nursery school during an autumn and a winter period. Measurements of indoor and outdoor particle concentrations have been carried out by using three different filter efficiency configurations in the school equipped with a balanced ventilation system with heat recovery. The tested filters are respectively classed G4, M5 and F7 according to NF EN 779 (2012).