Comprehensive assessment brings out shortcomings in almost every school building

Consideration of the big picture is needed when evaluating aspects of the building with relevance for reporting of poor indoor air quality or symptoms. Even the most accurate longitudinal measurements do not remove the need for expertise and broad understanding of the different possible sources and causes of indoor air exposures. Finnish Institute for Health and Welfare (THL), in collaboration with Tampere University (TAU), studies the association between school buildings of Helsinki and pupil reported health symptoms. The present paper focuses on introducing the methods and classifications as well as presenting the results about the condition of the buildings. Characteristics of 53 school buildings have been assessed by visiting the buildings and by going through the previous building investigation reports. Visits relied mainly on visual inspections with an extensive checklist and some none intrusive momentary measurements about the dampness, pressure difference, and indoor air quality (IAQ). The major strength of the study is that all the possible school buildings in certain areas were inspected and assessed using the same methods, irrespective if the building had a long history of indoor air problems or not. That makes it possible to evaluate the general prevalence of the problems in school buildings, which has been highlighted as an open question by the National Indoor Air and Health Program 2018-2028, coordinated by THL. The first results indicate that every school building has its shortcomings. However, none of the studied buildings was in a very bad condition either. The results indicate that it is not possible to draw a clear line between the buildings with 'good' or 'poor' IAQ.Peer reviewe