Indoor Air Quality Monitoring In Dwellings: Case Studies In Madrid, Spain

The quality of the indoor environment has evolved into a vital parameter for dwellings due to the increasing number of home-based jobs, with more people spending most of their time at home. Generally, the design and evaluation of indoor air quality in buildings depend on guidelines and recommendations from national and international standards. In a building stock in which mechanical ventilation is not mainstream, it is necessary to evaluate the natural ventilation habits and their impact on indoor air quality. This article describes a methodology to assess indoor air quality using four case studies in which habits and occupancy are representative samples of dwellings in Madrid, Spain. Temperature, relative humidity, formaldehyde, particle matter (PM), and carbon dioxide (CO2) concentrations have been measured over several months. The analysis of these values leads to conclusions that each pollutant has a different source. For example, Formaldehyde concentration depends mostly on indoor finishes and materials; indoor activities impact PM concentrations. The results showed high formaldehyde concentrations in the case study decorated with oil paintings, whereas bedrooms with insufficient ventilation showed consistently high CO2 concentrations. Finally, well-ventilated rooms showed high PM concentrations due to the smoking habits and pets that live with the family.