Fungal Glossaries, Part I

Each month we publish a newsletter titled IAQ Website of the Month. The excerpt below was originally published in the May 2013 newsletter.

If you take samples for mold, you’re probably familiar with common taxonomical groupings such as Cladosporium and Aspergillus.  But what if you find something more exotic?  Where can you go to learn more about the not-so-common types of mold?

Fortunately, there are several online resources.  In fact, there are so many, I’m making this a two-part newsletter.  This month I’m featuring websites from commercial laboratories and next month I’ll feature other resources.
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Sampling in the face of variability

The concentrations of IAQ contaminants almost always fluctuate over time.  Therefore is it best to log data over time, whenever possible.  Technology, and more importantly, budget constraints may prevent us from logging data over time.  That means we must show up on a given day and measure that point in time.  This method gives us a random reading from a normal day.

If we only have one shot at taking a measurement, some advocate aggressive sampling to simulate the absolute worst case maximum scenario.  Let me give you some examples of trying to simulate the worst case maximum scenario: Continue reading

Mold: More than a Number

Viable Air Sample for Mold

You may take air samples when trying to identify a hidden mold problem.  The total number of spores in the complaint area should be compared to indoor and outdoor controls, or more accurately, “references”.  For example, if you find 10,000 spores per cubic meter in the complaint area, and only 1,000 in the reference samples, there is a high likelihood of indoor amplification.

Although it’s important to look at the total numbers, it’s critical to also make comparisons of the types of mold.  Each type of mold is unique.  There are some types that will predominantly grow on leaves outdoors.  These don’t have an apetite for building materials and will rarely be found growing indoors.  Other types, however, do have the enzymes needed to digest common building materials in its quest for more food.

A few references can help you make a distinction between types of mold typically found outdoors and those that can grow on building materials.  I’ll summarize a few of these references below: Continue reading