A great deal of concern has arisen recently regarding the potential adverse effects of indoor fungi. Our understanding of this complex problem has been hampered by a lack of standardized protocols for performing an indoor assessment for fungi. Without such standards, it is difficult to compare results from one study with those from another or to measure the effect of indoor fungal contamination on a building and its occupants.

We reviewed the medical literature and here describe a hypothesis-driven approach to planning, sampling, and interpreting the results of indoor assessments for fungi.

Fungi cause 3 primary adverse effects: (1) they can damage a building, (2) they can render a building unpleasant to live in by looking and smelling bad, and (3) they might cause adverse health effects in sensitive individuals. Sampling methods used to test hypotheses include air sampling for spores, measurement of allergens in house dust, and determination of microbially generated volatile organic compounds, ergosterols, glucans, and mycotoxins, as well as environmental conditions that lead to fungal contamination.

Standardized approaches for performing and reporting assessments of indoor fungi are essential if our understanding of this complex field is to improve.