Variability in viable and non-viable mold spore sampling results
Swenson, L., Robbins, C. and Geer, W.
2002 AIHCE02, Technical Poster Sessions
Swenson, L., Robbins, C. and Geer, W., (2002), "Variability in viable and non-viable mold spore sampling results", AIHCE02, Technical Poster Sessions.
Abstract:
Industrial hygienists are asked to conduct sampling to determine the presence or extent of mold and to make recommendations for mold remediation. We are often faced with the question of the significance of one or two spores or colony forming units (CFUs) that are found indoors but not outdoors or in unaffected areas. Although the particular mold type may provide clues to possible indoor reservoirs or other issues, the presence or absence of a few spores or CFU may represent the inherent limitations of short term sampling and analysis of mold particles from the air. Little information has been published on the variability between duplicate samples taken concurrently. This paper discusses the types of fungal spores and levels of spores identified during sampling indoors and outdoors and provides a comparison of air sampling results for viable and non-viable mold spores. It presents an analysis of low numbers of mold types in paired samples and provides an estimate of the uncertainty around a few spores or CFUs in short-term viable and non-viable samples. Sampling is conducted outside, in unaffected areas (when possible), and in potentially affected areas. Duplicate samples of each type at each location are obtained in sequential order. Paired sample results indicate there is considerable variability for these short-term sampling techniques, especially in the ability to detect low levels of particular spore or CFU types.