Volatile organic compounds emitted by humans indoors– A review on the measurement, test conditions, and analysis techniques

The impact of indoor air quality on human health is gaining importance as people spend 90% of their time indoors. It has been established that human occupancy is a significant contributor to indoor Volatile Organic Compound (VOC) concentrations and is of significant concern regarding occupant health, and yet human VOC emissions remain largely uncharacterised. In the current study, we review recent research that examines the contributions of humans to the indoor VOC profile in occupied spaces, with a focus on study characteristics. This investigation identified a hierarchy of factors contributing to inter-study variations in human biogenic VOC (HVOC) levels measured indoors. We found that the factors contributing to the variation in reported HVOC emissions are related to the sampling techniques used, the test conditions, occupant related factors sample analysis. Contrasting findings on issues such as the effect of nutrition and smoking are discussed. Conclusions were reached about the recent advancements and nature of results and the need to use larger datasets, and recommendations regarding global guidelines and future testing have been made. We advocate for a unified approach in future studies, promoting more coordinated data collection and reporting and fostering the development of impactful applications.