Managing air quality in buildings

We spend 90% of our time indoors, Regional Director and Head of Sustainability Annabel Thorne says we often take for granted that the air we breathe indoors is of good quality when it is not.

Over the years, headaches, fatigue, breathing problems, coughs and other such ailments can become part of our day-to-day existence, without consideration that the air we breathe could be contributing to an exacerbation of such symptoms. We spend more than 90% of our time indoors, so even low concentrations of indoor air quality (IAQ) pollutants can cause a negative effect on our health. 

IAQ risks  

We often use our sense of smell to guide us in detecting anything unusual in the air, but sometimes there are pollutants lurking around that are below our olfactory sense threshold that our nose cannot detect. These range from organic pollutants, such as formaldehyde and volatile organic compounds (VOCs) to inorganic pollutants, such as ozone, nitrogen oxides and particulate matter (PMs), which come from many sources. These include products used to construct, refurbish, or clean buildings, to associated fixtures, fittings, and furnishings, as well as human activities. 

Benefits of good IAQ 

Although COVID-19 was based on a virus, the recent pandemic reminded us of the importance of the quality of the air we breathe. However, the importance of a good IAQ, largely free of organic and inorganic pollutants, should not be underestimated. 

Several studies have shown how good IAQ in hospitals have reduced the recuperation time of patients, increased attention span and learning ability of students, lower absenteeism, ‘presenteeism’ and higher productivity for office employees and so on. 

Improving air quality  

These pollutants can cause certain adverse health issues so they should be treated. IAQ sensing equipment can be used to pick up most pollutants that we encounter, although IAQ monitors vary in their mode and method of operation, these days hand-held IAQ monitors are sensitive enough to detect pollutants at very low levels. A good standard of IAQ is best assured at the design stage of a building. 

Tackling poor IAQ in buildings 

Normally a new building or refurbishment would try to limit the utilization of low VOC materials for construction by specifying the use of low VOC construction materials. However, planning to ‘off-gas’ the building by forced ventilation between practical completion (PC) and occupation, would also be useful. 

However, useful checks of the IAQ between PC and occupation would provide a reassurance of good air quality. In existing buildings where the IAQ is suspected to cause the occupant health effects, a ‘sweep’ of several rooms within the building/s would be taken to form a high-level review of the IAQ using hand-held ‘active’ IAQ monitors. This would then be followed by detailed measurements taken in the ‘problem-rooms’ using passive sampling IAQ equipment, which would measure the levels of various pollutants over longer time periods, such as 1 week to 1 month, and using passive samplers, which would be analyzed in the laboratory. 

Equipment that can detect and log IAQ pollutants at regular time periods over several days could also be employed to follow the course of levels of certain pollutants over a specific period to show fluctuations, which can often help in relating levels to potential activities and sources. 

Air Quality Guidelines 

The World Health Organization (WHO) has put air quality ‘guidelines’ in place, but there is no legislation in place to ensure compliance. ‘Green’ building certification schemes, which often promote the creation of good IAQ environments, remain the best way to ensure a ‘healthy’ indoor environment for occupants. BREEAM (the Building Research Environmental Assessment Methodology) and the WELL Standard are two examples where IAQ is the focal point of a healthy building, by ensuring the specification of low VOC materials and good ventilation, but also measurement-based validation of good air quality. 

Pushing the green agenda 

When buildings are being developed, the specification of low pollutant materials and the frequent testing of IAQ should be high on the agenda. 

The impact of the indoor environment on health has been reinforced by the COVID 19 pandemic. By being aware of the importance of the IAQ we can both optimize our performance and guard against certain risks by taking steps to mitigate poor air quality, both for new buildings and existing buildings. Good air quality is not a luxury, but a necessity.