Mold Challange 2

[Guest guest]

Here is the update on the Mold Analysis Challange. It should address

the issues many of you have discussed. Also, someone asked that I

teach them how to interpret the results. That's the real trick to

this art and I hope the following is helpful.

With the knowledge and experience my clients had, I asked why they

were even considering this house because of the lab report (from

another company, not me). They said they really liked the house, it's

the best they've found in 7 months of looking and they could find no

reason why there would be any mold growth in the house.

I understood that, and besides, I had questions about the lab data.

The questions increased to concerns as I inspected house.

The total levels of mold inside the house were actually quite good,

as several of you pointed out. Of concern, however, was Stachybotrys

and Memnoniella (similar to Stachybotrys). The airborne data were

much, much higher than I usually see even in water damaged houses.

Also of concern was the outside levels - unless the wind was blowing

a lot of dust. Once I found out they were collected while it was

raining my doubts inceased! I would expect the rain to " wash " almost

all particles of any kind, including mold spores, out of the air and

onto the ground. If I were to ever get a zero result, it would be in

the rain or snow.

My questions about the lab data further increased as I inspected the

house. Yes, it had a basement but it was a walkout basement and was

very dry - the RH was 31% which was lower than upstairs or outside at

similar temperatures. (Therefore, the Specific Humidity calculated as

nearly identical).

The floor was a slab with minimal hairline cracking in a few of the

seams with no indications of moisture and no odor. Landscaping was

excellent. The attic showed no signs of moisture or odor and was

extremely well separated from the living space.

The HVAC in the basement was dusty and needed cleaning but the A/C

was only 1 year old and clean. Stachybotrys is unusual in A/C because

cardboard is unusual in A/C.

The only evidence of any damage or defect was two locations where the

plastic-covered fiberglass insulation on the walls had been patched.

I asked if the owner had a cat or dog and they confirmed that a dog

had pawed the insulation and that they had patched it with new

insulation.

I could find absolutely no place, not even with a stretch of my

active imagination, where mold could be growing. So if there is no

mold growth inside and it had been raining outside, where did the

airborne mold come from? I was now faced with the possiblity that the

samples were a false positive - very hard to do unintentionally.

We still had to answer the question about the accuracy of the test

results before they could make a decision on whether or not to buy

the house.

Another reason to question the lab results was that he had spent two

hours in the house with no reaction. Other houses caused a reaction

within minutes.

They asked me to repeat the previous sampling. I consented only after

we agreed on how to interpret the results.

1. If my samples had similar results, then the previous ones were

confirmed. Further investigation would be needed to identify the well-

hidden source(s) of Stachybotrys and Memnoniella. They declined the

further investigation offer and said they would simply back out of

the deal.

2. If my sample were higher than the previous ones, they would just

back out.

3. If my samples had lower Stachy the risk was still too high and

they would back out.

4. If my samples were significantly different and especially if they

had zero Stachybotrys and/or Memnoniella, then they would proceed

with the purchase. However, they asked for and I agreed to additional

sampling for future use. This included culturing in addition to the

spore traps. Two different culture media were used. One that was

selective for Penicillium and Aspergillis and the other selective for

Stachybotrys.

I'll let you know the spore trap results in a couple of days. The

culture results will take another 10-18 days.

In the meantime, what do you think?

Carl Grimes

Healthy Habitats LLC