Toward a critical assessment of indoor environmental quality standards

Building design and operation requirements regarding indoor-environmental quality (IEQ) are of direct relevance to occupants' needs. In most buildings, occupant-related requirements pertain to the provision of conditions that support optimal task performance and are subjectively perceived as comfortable or pleasant. Codes, standards, and guidelines that specify IEQ requirements are commonly viewed as the main sources of reference for practitioners, who are expected to follow the provisions in these documents and provide corresponding proof of compliance. However, actual code compliance processes are not always accompanied by critical reflections regarding the evidentiary basis of the entailed mandates and recommendations. It is thus necessary to critically scrutinise standards in view of explicit or implicit references to the scientific basis of the entailed mandates. The present contribution explores and details a path toward such a critical assessment. To this end, we considered a number of typical and frequently referenced standards pertaining to thermal, visual, and air quality aspects of indoor environments. The results of this illustrative assessment effort highlight the scope and limitations of the standards' default approaches to the definition of IEQ-relevant requirements. Moreover, they point to considerable gaps in the chain of evidence from standards' immediate content to the underlying factual sources.