Page 36 - U4SSC Simple ways to be smart

Air quality has traditionally been measured using sophisticated monitoring stations, each costing
hundreds of thousands of Euros. These are very accurate, but they are not numerous and, in many
places, they do not exist. This means that many places are unaware of the types of air quality
problems they face, or the extent. Larger cities have been able to establish good monitoring
programs with sophisticated websites that present the data, and programs to improve the quality
of air, but this has been beyond the reach of most cities.

The solution

Low-cost sensors (LCSs) for air monitoring, combined with the IoT could be a cost-effective solution
to assess the air quality in a city, in both outdoor and indoor environments. There are hundreds
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of commercially available LCSs with costs ranging from hundreds to several thousand Euros. Prices
depend on the quality and the extent to which collected data are post-corrected (processed to
improve data quality using machine learning or algorithms).

The sensor modules can be powered by solar panels since they have a very low power consumption
and the data is collected in .csv files that take up very little storage space. Planning is involved to
decide where the sensors must be placed, how they will be looked after, if data will be collected
in real-time (over a network) or whether memory cards will need to be read, and how frequently
the data will be collected. The sensors, and possibly other infrastructure, will need to be purchased
and installed. Depending on the city processes, this could take 6 months to a year to implement.

The results need to be communicated, usually through a website or mobile app. There are clear
standards on air quality for the different pollutants that the sensors measure. So, it would be simple
to compare the data recorded with the standards, making it easy for everyone to understand the
meaning of the results.

The use of low-cost sensors for air quality monitoring has generally been approached through
citizen science and educational activities, engaging residents and students in the measurement

and analysis.A growing global network of home enthusiasts is using kits to build their own sensors
and collect data which is shared on websites.
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The number of sensors used can be scaled to suit the budget. Where there is currently no monitoring,
even one sensor would give useful data. However, sensors installed where air quality is expected
to be poor (near highways, industrial or construction areas, fire areas) and where one would like
air quality to be good (schools, libraries, hospitals, parks) will be the most useful for the city.

Results

With some support, it is possible for a city to collect data about air quality from multiple locations,
relatively cheaply. Such data can be used to visualize air quality and to connect it with the
consequences for health, the economy, and quality of life. Such data would supplement official
country data, increasing the spatial coverage, and would fill the data vacuum where no monitoring
is currently undertaken.

24 U4SSC: Simple ways to be smart