air cleaning

On June 24, 2023, ASHRAE approved the publication of Standard 241-2023 Control of Infectious Aerosols. The purpose of Standard 241 is “to establish minimum requirements for control of infectious aerosols to reduce risk of disease transmission in the occupiable space” of buildings by defining “the amount of equivalent clean airflow necessary to substantially reduce the risk of disease transmission during infection risk management mode”.

The scientific community has been aware of the importance of indoor air quality (IAQ) for many decades, but the COVID-19 pandemic has brought a significantly higher level of attention from the general public and governmental entities to this theme. However, IAQ comprises hundreds of other parameters besides infectious pathogens, many of which can equally impact the health, comfort and well-being of occupants.

A Canadian provincial government has initiated a collaboration with the Indoor Air Quality (IAQ) team of the National Research Council of Canada (NRC) to conduct a controlled intervention study to determine the effectiveness of portable air cleaners (PACs) in reducing indoor air contaminants in 2 schools.

Indoor air pollution is a significant concern due to its adverse effects on human health and productivity. With people spending most of their time indoors, exposure to indoor air contaminants can lead to various health issues, including respiratory problems, cardiovascular diseases, and even an increased risk of lung cancer and premature mortality. Additionally, poor indoor air quality can result in short-term symptoms like headaches, eye and throat irritation, fatigue, and asthma, impacting workplace productivity and absenteeism.

International Energy Agency (IEA) Annex 78 was launched in 2018.

As part of the mandated standards for estimating the energy performance of buildings CEN 16798-1 and -2 was developed to provide input for the indoor environment (thermal comfort, air quality/ventilation, lighting, acoustic) to energy calculations and design of buildings with its heating, cooling, ventilation, and lighting systems. A revision of this standard has now been started.

This paper presents the initial reflections in the frame of Subtask 1 – Setting the Metrics of the IEA EBC Annex 68 – Indoor Air Quality Design and Control in Low Energy Residential Buildings. The first step of IEA Annex 68 aims at summarizing the current knowledge on target pollutants for residential buildings and at evaluating indoor air quality (IAQ), i.e. how to define indices that provide useful information allowing to achieve low risks for health in indoor spaces, and how to enable the comparison of solutions for achieving high IAQ taking into account energy efficiency.