Multiple point IAQ measurements in office buildings over time indicated that while IAQ might vary due to different behaviours of people, or different use, the CO2 levels showed insignificant variation. In contrast, VOC levels exhibited slightly higher variations, due to the existence of differing types of VOC sources.
In Supermarket stores more than one IAQ kit is not necessary in the way these stores are currently operated, except from the aisles with detergents, animal food etc., where VOC levels could significantly differ.
In some office buildings, IAQ measurements recorded lower levels of CO2 during operating hours in contrast with the higher levels that occurred during non – operation hours, due to the presence of people in the area, suggesting that the ventilation system works properly during normal working hours and not during the rest of the day which is necessary for the specific building. Moreover, the VOCs levels in most buildings were higher during non-operation hours, because of the emission of materials and the reduced operation of the ventilation system.
The results also showed that in most buildings regardless of the type, CO2 concentrations are higher during the winter season, due possibly to reduced ventilation rates to conserve energy or to more intense mobility of people at this period compared to the summer. In Supermarket stores a more stable trend of CO2 was observed, during the summer season, in contrast to the winter season where more fluctuations occurred. Furthermore, regarding VOCs, no relationship was observed between the pollutant and the corresponding periods in any type of building.
According to the physical inspections undertaken by MacWhirter Ltd, in most Greek buildings the operation of the A/C equipment, considering its type and age, would be deemed as satisfactory. Using the information gathered from the inspections, in some cases, the HVAC systems could be only radically improved by investing in the latest equipment, which might not be economically sensible. Results obtained so far from simultaneous measurements of HVAC parameters and IAQ indicated that a link between them depends on the use of the building, the maintenance of the HVAC system, and the age of the HVAC system. There was no clear link with energy consumption.
In conclusion, IAQ appears satisfactory in most buildings tested and there are no obvious links with energy consumption in the systems tested to date.