The Relationship between Measured Moisture Conditions and Fungal Concentrations in Water-Damaged Building Materials

Abstract

We determined the moisture levels, relative humidity (RH) or moisture content (MC) of materials, and concentrations of culturable fungi, actinomycetes and total spores as well as a composition of fungal flora in 122 building material samples collected from 18 moisture problem buildings. The purpose of this work was to clarify if the is any correlation between the moisture parameters and microbial levels or generic composition depending on the type of materials and the time passed after a water damage. The results showed an agreement between the concentrations of total spores and culturable fungi for the wood, wood-based and gypsum board samples (r > 0.47). The concentrations of total spores and/or culturable fungi correlated with RH of materials particularly among the wood and insulation materials (r > 0.79), but not usually with MC (r < 0.45). For the samples collected from ongoing damage, there was a correlation between RH of materials and the concentrations of total spores and culturable fungi (r > 0.51), while such a relationship could not be observed for the samples taken from dry damage. A wide range of fungal species were found in the samples from ongoing damage, whereas Penicillia and in some cases yeasts dominated the fungal flora in the dry samples. This study indicates that fungal contamination can be evaluated on the basis of moisture measurements of constructions in ongoing damage, but the measurements are not solely adequate for estimation of possible microbial growth in dry damage.

Characteristic and Concentration Distribution of Culturable Airborne Bacteria in Residential Environments in Beijing, China

“…According to several studies, the moisture content of building materials, relative humidity and temperature (Pasanen et al, 2000;Ritchkoff et al, 2000), outdoor concentrations, air exchange rates (Kulmala et al, 1999), human activities (Buttner and Stetzenbach, 1993) and the number of people and pets (ACGIH, 1999) significantly affect the levels of indoor bioaerosols. In addition, housing conditions, the activities and lifestyle of occupants can contribute to the varying concentrations.…”

An experimental set-up for real-time continuous moisture measurements of plywood exposed to outdoor climate

“…extensively [11], [12], [13], [14], [15] and [16]. For plywood far less research has been carried out, yet this is critical regarding the Construction Products Directive (CPD; [17]) as from which emanates the need for research in the field of service life prediction and planning as to satisfy the requirements for Annex I [18].…”

Spectrum and Concentration of Culturable Fungi in House Dust from Flats in Warsaw, Poland

“…It is well known that bad technical condition of the building (poor ventilation, dampness, wet walls) favour the fungal development and the indoors fungal spores concentration (Garrett et al, 1998;Pasanen et al, 2000). In the present study, the most important factor associated with increase of concentration of fungi, especially in the bathrooms, was ventilation.…”