Monitoring Viable Fungal and Bacterial Bioaerosol Concentrations to Identify Acceptable Levels for Common Indoor Environments

摘要

Bioaerosol concentrations between 200 -450 CFU/m3 have remained largely uncharacterizedwith respect to potential indoor airquality concerns. This research provides forfurther description of indoor bioaerosolconcentrations and concludes that 3 0 0CFU/m3 of non-toxigenic or non-pathogenicorganisms should be typical for normal, non-immunocompromisedenvironments. With theexception of Cladosporium, no organism shouldindividually contribute more than 150 CFUfm3.Furthermore, it is concluded that > 300CFU's/m3 and/or not meeting the above criteriashould incite some additional level ofinvestigation with respect to; the bias ofprominent outdoor bioaerosol(s), adequatefiltration, indoor humidity and microhumidityenvironments, and/or potential indigenouscontamination source(s). The author cautionsthat the >300 CFU/m3 threshold is notintended to represent any threshold havingmedical or health significance and/or necessarilyrepresentative of an unacceptable indoorenvironment. The >300 CFU/m3 is intended tobe a "reactionary threshold" to incite furtherinvestigation as to the cause(s) of what isperceived to be an above average viableconcentration for indoor bioaerosols. Theauthor further concludes that outdoor samplingshould only be utilized in the relativecomparisons to individual indoor componentsand that indoor/outdoor ratios involving totalCFU/m3 concentrations should not be utilized asa specific mechanism to evaluate acceptableindoor bioaerosol concentrations.