An introduction to the indoor air quality monitoring guide and why indoor air quality is important.
The Covid-19 pandemic has increased awareness of the immediate
need to improve indoor air quality inside buildings. Doing so
effectively, without compromising the comfort of occupants, demands
dedicated monitoring of carbon dioxide, temperature and humidity in
the indoor environment.
Indoor air quality and public health
The state of indoor air quality in the UK - and
its effects on our health - has come under new scrutiny due to the
airborne spread of coronavirus in poorly ventilated indoor
However, many institutions, including the Chartered
Institution of Building Services Engineers (CIBSE, UK),
the Scientific Pandemic Insights Group on
Behaviours (SPI-B, UK) and the Building
Engineering Services Association (BESA, UK), are anxious
that management of indoor air quality should continue beyond the
pandemic. This is due to the significant impact of indoor
air quality on our overall health.
Poor indoor air quality, aside from encouraging the spread of
contagious diseases, has been linked to respiratory illnesses (such
as asthma and cancers), Alzheimer's disease, heart disease and
inflammatory conditions. Considering that people in the UK
spend up to 90% of their time indoors, it is undeniable
that indoor air quality is affecting our health.
Monitoring the indoor environment effectively provides the first
step to improving indoor air quality and promoting long-term public
Where to begin with monitoring indoor air quality:
Indoor air pollutants include particulate matter, carbon
monoxide, carbon dioxide, radon, volatile organic compounds (VOCs),
mould and humidity.
Monitoring for many of these pollutants can be costly and
impractical; however, cost-effective and accessible monitoring
options are available for measuring CO2.
Carbon dioxide, while naturally present in the air, also
builds up in occupied spaces due to occupant
respiration. If levels of CO2 are consistently high in
an occupied space, it suggests that there is an inadequate supply
of fresh air and that indoor air quality is poor. An understanding
of CO2 levels in an indoor space can therefore inform
strategies to improve air quality (e.g. increasing ventilation
Methods for improving air quality, however, such as ventilating
through natural or mechanical means, can adversely affect
indoor temperature and humidity levels, both of which are
important for indoor comfort. Unexpectedly low levels of
temperature and humidity can also reveal instances of energy loss
resulting from increased ventilation rates. Any attempts to improve
indoor air quality must therefore consider and balance the
implications for occupant comfort and energy costs.
Monitoring CO2, followed by temperature and
humidity, is a simple, cost-effective way to begin building an
adaptable indoor air quality strategy that also prioritises and
improves occupant comfort and saves energy.
CO2 Data Loggers: Visualising Air Quality
Go back to:
How to Monitor Air Quality Effectively
References and further reading