Indoor Air Quality
To show that benchmark boundaries are not set inappropriately at the expense of Indoor Air Quality, IAQ measurements were undertaken in 64 sample buildings across Europe.
To achieve this at a reasonable cost during the project’s period, a compact Indoor Air Quality system was developed and placed in buildings across Europe with HVAC systems larger than 12kW, in order to investigate whether a relationship exists between IAQ and energy consumption. The study was also to provide confidence that the benchmark energy consumption boundaries used in iSERVcmb were not being obtained at the expense of IAQ.
- The indoor air quality of the majority of buildings tested was satisfactory.
- CO2 concentrations were at low values in the majority of buildings tested, indicating a good air quality and adequate ventilation with minor exceptions.
- Overall, VOC concentrations showed no major problems, also indicating that ventilation is adequate.
- Indoor Air Quality shows some correlation with the age and the maintenance of the HVAC system.
- There is no obvious correlation between IAQ and energy consumption
- A portable standalone IAQ system can measure IAQ successfully.
- Turning HVAC systems off at night does not lead to a decreased IAQ except in specific circumstances where Volatile Organic Compounds remain at higher levels during the non – operation of the buildings due to emission of materials in super market stores or due to the presence of people e.g. clean-ers, after normal operational hours.
- One portable IAQ system can successfully represent a building which has similar activities throughout. For example, in Super Market stores the IAQ does not appear to vary significantly across a store, except for where there are detergents, in which VOC values differ significantly.
To check comparability within buildings, cities and Member States, a large number of initial measurements were taken firstly from one Greek building (which served as a pilot building) and then from a number of Greek Offices and Supermarket stores. Finally the IAQ kits were sent to several European Cities to explore the variation of IAQ across Europe in Offices and Supermarkets.
The sensors employed were able to continuously monitor temperature, relative humidity, CO2 as well as VOC (Volatile Organic Compounds) levels, while existing energy monitoring systems were used to provide information regarding the building and HVAC system energy profiles.
The buildings were classified as Offices, Supermarket or Electronics Stores. Greek Offices are shown separately to facilitate comparison with the findings in Offices in the rest of Europe. Air quality levels were distinguished into 3 categories corresponding to ‘Good’, ‘Acceptable’ and ‘Poor’ for CO2. ‘Comfort’, ‘Decreasing comfort’ and ‘Discomfort’ were the descriptions used for VOCs, due to exposure to multiple factors.
- To read the iSERVcmb Overview report, download a copy from the “Overview Report” report at www.iservcmb.info/results.