Air quality monitoring in an office environment

Office on a quiet road

  • Two of the Siba IoT sensor boxes, namely the IAQ Indoors and the PM Particulate Matter sensor boxes were installed at two different office spaces at the Company Datamed S.A, in order to obtain real-time continuous monitoring of internal air quality, as part of their ISO 14000 accreditation procedure.
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  • The pollutants monitored were particulate matter, expressed as PM1.0, PM2.5 and PM10, carbon monoxide, carbon dioxide, ozone and volatile organic compounds (VOCs). The quality of the microclimate, temperature and humidity was also concurrently assessed.
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  • The first office space is used as an office where two people work, has air conditioning, two big windows and is situated at the back side of the building, overlooking a quiet small street.
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    • Internal air pollutant concentrations, i.e. carbon monoxide, ozone and VOCs remained at very low levels, much lower than ambient air standards, as it can be seen in figure 1. There was no impact from external air pollutants when a window was left open.
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  • Particulate matter concentrations on the other hand , and particularly PM10 were detected and ranged between 10 and 20 mg/m3, see figure 2. It was observed that PM10 increased sharply to levels above 40 mg/m3, which is the ambient air standard, when a vacuum cleaner was applied at the end of the working day, on both days. The origin of particulate matter is most probably dust accumulated in the carpet.
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Fig. 1 - Pollutant concentration fluctuation, in the first office space
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Fig. 2 - Particulate matter concentration fluctuation, in the first office space

Office on a busy road

  • The second office space is situated at the front side of the building, has three windows overlooking a very busy road. The space interconnects two separate parts of the office and people cross often from one part of the office to the other. During the experiment one person was present in the space and the air conditioning was on .
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  • Each time an employee passes through, a small peak in PM10 concentration is observed probably as a result of dust collected on the floor carpet, see figure 3 . Thus by measuring the number of peaks we can estimate the number of people who move between the two office parts.
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  • When a window is left opened there is a marked increase in CO concentration in internal air, as shown by the orange line in figure 4, caused probably by the exhaust gas of passing cars. However the concentration of this pollutant fell rapidly when the window was closed.
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Figs. 3 and 4 - Concentration of particulate matter and internal air pollutants in the second office space

Why is it important

Continuous monitoring of the concentration of air pollutants in the office environment is very important for the health and well-being of employees. For this reason air quality monitoring is becoming an obligatory requirement for establishing an environmental management policy according to ISO 14000 Environmental standards.