How to predict if mold will grow inside of gypsum wallboard-faced walls.. measure the humidity inside of the wall cavity..

[Guest guest]

Barb,

This is an interesting paper that does the work of predicting whether

stachybotrys mold will grow in a wall or produce mycotoxins inside the wall

that accumulate there.

If the RH inside of the wall can be kept down, then mold can't/won't grow!

________

Indoor Air. 2004 Jun;14(3):196-9.

*Wall relative humidity: a simple and reliable index for predicting

Stachybotrys chartarum infestation in dwellings.

*

Boutin-Forzano S, Charpin-Kadouch C, Chabbi S, Bennedjai N, Dumon H,

Charpin D.

Department of Chest Diseases and Allergy, Hôpital Nord, Marseille,

France.

Because the indoor mold Stachybotrys chartarum has been considered as

potentially responsible for serious health effects, its identification in

dwellings with water damages is of utmost importance. As such dwellings are

many, it would be of great value to have a simple and reliable index for

predicting its presence. The aim of the study was to compare measurements of

wall relative humidity (RH) to mold identification in 458 samples from 100

dwellings. Mold identification was performed by direct microscopic

examination of a sample collected on the wall by the gummed paper technique.

Mean (+/- s.d.) wall RH (%) was much higher (97.0 +/- 6.1) on the 30 samples

where S. chartarum was identified compared with the 291 samples where other

molds were identified (41.8 +/- 36.9) and to the 137 samples where no molds

were identified (38.9 +/- 34.8). There was no straightforward relationship

between wall and room RH. In conclusion, this study clearly demonstrate that

the simple measurement of wall RH can be used as a reliable index for

discarding and suspecting S. chartarum infestation in dwellings. PRACTICAL

IMPLICATIONS: This paper suggests that very high relative humidity (RH)

within walls is a strong risk factor for their infestation with the 'toxic

mold' Stachybotrys chartarum. *Besides, data from the literature demonstrate

that other molds are able to produce mycotoxins when RH is very high. *Thus,

measurement of wall RH, which is easy to perform and very cheap, could be

used as a screening tool to select those dwellings where mold identification

should be performed and remediation should be promptly carried out.

Publication Types:

* Research Support, Non-U.S. Gov't

PMID: 15104787 [PubMed - indexed for MEDLINE]