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Kenneth Hellevang

Kenneth J. Hellevang
Extension Engineer
North Dakota State University

Room 117 Agricultural & Biosystems Engineering Building
North Dakota State University
Dept. 7620
P.O. Box 6050
Fargo, ND 58108-6050

Phone: 701-231-7243
Fax: 701-231-1008
Email: Kenneth.Hellevang@ndsu.edu 

Local Resources

Contact your local Public Health Office in your county or city, or the local Extension Service office.

Air Testing

Look in the telephone book yellow pages under "Air Quality Measuring Service" or "Laboratories-Testing"

Identifying Mold through the NDSU Plant Diagnostic Lab

People concerned about potential mold problems may have samples tested at the NDSU Plant Diagnostic Lab.  Samples will be evaluated for the black mold organism, Stachybotris, or for other organisms that might cause a potential health concern.

To submit a sample, it is best to bring in the mold on the piece of wall board, wood, carpet, or whatever the questionable substance is on.  A small piece, about 1 square inch is sufficient, but larger is acceptable. 

Always use protective gloves when handling mold (e.g. dish gloves, nitrile gloves, etc). In severe infestations, a dust mask and eye goggles are also recommended in addition to the protective gloves. Note that in severe infestations, remediation may require trained professionals since disturbing the contamination can release the spores into the air at a higher rate, thus making a mold problem potentially much worse. The cost is $30.00.

Results will be reported within a week in a letter explaining what was found and why it might pose a health concern, and suggestions for how to manage the possible problem.

NDSU Plant Diagnostician
Dept. 7660-306 Walster Hall/206Waldron Hall
P.O. Box 6050
Fargo, ND 58108-6050

Tips on how to collect a mold sample

Promoting mold growth on agar media mold kits sold in stores is discouraged, since the results are seldom informative. Why? Because mold spores are everywhere and standardized protocols that are required to make any sense of the data are lacking.

Instead, find areas on sheetrock, carpet, wood trim, or other organic materials that appear discolored. Sometimes peeling paint can indicate an area where mold may be growing. From these areas, collect a small portion of the discoloration. For example, if sheetrock is discolored, peel off some of the paper layering with the discoloration. For discolored wood, consider shaving off a thin layer of the affected wood. For carpet, try to collect mold spores with clear Scotch tape, or, if possible, cut out a small area of discoloration.

Another method to collect a sample is to place a piece of clear Scotch tape over a discolored area, sticky side facing the discoloration. Press gently on the tape, then lift the tape off the affected material.

Yet another method to collect a sample is to use a cotton swab to swab the discolored area.

All samples (material, tape-lifts, cotton swabs) should be placed in a labeled re-sealable baggy.

There are limitations to the type of mold evaluation that the NDSU Plant Diagnostic Lab can do. First, it cannot compare the mold spores present in the indoor environment to the mold spores present in the outdoor environment. Second, we cannot determine the EXTENT of mold contamination, which is more important than presence of mold. Mold is everywhere and every indoor environment will likely have mold somewhere. How much contamination is present and whether it is actively growing are two questions the NDSU Plant Diagnostic Lab cannot address. Another important limitation is that a serious, mycotoxin-producing mold may not be detected on a submitted sample (even though other molds may be detected). Lack of detection does not mean a mold is  not present or actively growing in an indoor environment. Detection and accurate identification depends on the quality of the sample and other factors beyond the submitter’s and the lab’s control.

Mold in homes is typically darkly pigmented – e.g. black, brown, olive-green. If you see white discoloration on cement, it is probably not mold (instead, it is probably salts from water that may be wicking up the cement).

Contact Agricultural and Biosystems Engineering

NDSU, Dept. 7620
P.O. Box 6050
Fargo, ND  58108-6050
Phone: 701.231.7261
Fax: 701.231.1008




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