Post Remedial Assessment and Clearance Criteria for Mold Remediation Projects

Post-remedial collection of 2,193 fungi samples were evaluated as a component of a three (3) tiered clearance criteria for mold remediations projects. Criterion #1 was the visual evaluation of remediated areas for the absence of fungal growth. Criterion #2 was the visual evaluation of surfaces in remediated areas for the absence of visible debris. Criterion #3 involved the evaluation of total fungal bioaerosol samples with a pre-defined post-remedial clearance criteria of < 2,000 particles/m of total fungi, with individual subcategories composed of <666 particles/m Cladosporium-like spores, <666 particles/m Aspergillus/Penicillium-like spores, <666 particles/m mixture of spores from other genera with no individual component comprising > 33% of this sub-category, and < 22 particles/m Stachybotrys/Memnoniella-like spores. Ninety-four (94%) of the population achieved clearance on the first assessment. One (1) percent of the initial failing population was related to fungal growth in the remedial area. Data obtained in this investigation support the modification of clearance criteria of Stachybotrys/Memnoniella-like spores to 88 particles/m. No specific health concerns were documented after the clearance of these areas; however, these guidelines are not intended to represent any specific medical or health related threshold regarding health. The authors conclude the three (3)-tiered clearance criteria provide a reasonable and obtainable clearance guideline, provided some latitude exists with respect to evaluating levels of all categories of fungal spores and the potential impact of an outdoor bias on a caseby-case basis.