The Approach of Including TVOCs Concentration in the Indoor Environmental Quality Model (IEQ)—Case Studies of BREEAM Certified Office Buildings

Abstract

The article analyzes the impact of measured concentrations of Total Volatile Organic Compounds (TVOC) emissions determined for four BREEAM certified buildings on the Indoor Air Quality Index (IAQindex) and the overall Indoor Environment Quality index (IEQindex). The IEQindex indicates the percentage of building users who are satisfied from the indoor environment. In existing IEQ models, currently the concentration of CO2 is mostly used to evaluate the IAQindex sub-component. Authors point out that it is recommended to use TVOC instead CO2 at pre-occupant stage where building is mainly polluted by emission from finishing products. The research provides the approach where the component related to the emission of TVOCs is implemented to IEQ model. The first stage of assessment was a test of the volatile organic compounds concentrations in case study buildings. Secondly, the analysis results were assigned into the number of dissatisfied users (PD(IAQ)) from the theoretical function given by Jokl-Fanger resulting from the Weber-Fechner equation. Finally, the overall IEQindex was calculated. The IEQ approach proposed in this paper is mainly based on a consideration of EN 15251 and scientifically accepted models.