Impact of the indoor environmental quality on employee well-being in a LEED-certified office building

Abstract

This paper deals with the assessment of the indoor environmental quality (IEQ) in two selected offices of the newly built green administrative building, which has achieved the second highest level of evaluation within the international LEED certification. The assessment of the IEQ was performed through real measurements of IEQ factors and a questionnaire survey. In each office, the total measurement time was set at 24 hours. The data recorded during the 8-hour working time were evaluated separately. During working hours, five employees were present in the first office (larger in area) and two in the second. Measurements were performed under natural conditions. For comparison, 24-hour measurements were repeated in the second office but without the presence of occupants. The results of IEQ monitoring showed that the legislative and LEED limits were not exceeded in any of the offices (either within 24 hours or during working hours). Exceeding the recommended LEED limit for TVOC concentrations in the second office by 34% during 8-hour working hours was related to the presence of people in this office. The measured daylight intensities in both offices met the minimum legislative requirement. The subjective evaluation shows that the occupants of the building themselves perceive IEQ positively. Although more than 50% of respondents said they feel fatigue, lethargy and have a headache while working in the office, given previous IEQ perception results, these symptoms may be related to the type of work performed rather than IEQ. Based on the results obtained from real measurements and a questionnaire survey, it can be stated that the monitored office spaces of the selected green certified building provide a quality, healthy and comfortable indoor environment that does not significantly interfere with their work performance.