How to Use Lighting to Find Mold in Buildings InspectAPedia® -
How to use and aim light to spot hard-to-see mold in buildings
How to find light colored mold
"Hidden mold" is easy to find with proper light
Links to photos of mold & stuff that is not but is mistaken for mold
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Proper use of and aiming of light or a flashlight when looking for mold in buildings can make the difference between
seeing and missing what might be the most important mold reservoirs in a given structure. Like the Purloined letter
problem mold may be in plain sight but may be hard to see, until you know how to look. One result is that people who
are testing mold often collect the "easy to see" mold but perhaps not the most important mold in a building. Here's how
to do it right - in this brief article.
For a more extnsive article with more photos and advice on how to use lighting and how to aim a flashlight to spot hard to see mold,
read USE A FLASHLIGHT. In most
cases, proper use of a flashlight can help spot mold on paneling and other building surfaces.
USING LIGHT to FIND MOLD - Using proper lighting to see important mold contamination in buildings
How and where you shine light is of crucial importance when looking for mold in buildings.
Light-colored
mold such as some members of the Aspergillus sp. and Penicillium sp. groups are often
the dominant problem-mold in buildings but these offenders are often missed by a casual inspection
because they can be hard to see on surfaces.
You need a bright flashlight and you need to know
how to use it. Shine the light along the surface being examined, not straight at it.
As you'll see in the mold photographs below, using your light carefully can make a big difference
in what mold you find and where you find it. Just looking for "black mold" risks missing the
important mold in a building.
Light colored mold next to obvious black mold -
Aiming a bright flashlight along this wall surface where dark mold was obvious shows a light gray/green fungal colony which in fact was far more toxic
and thus important to select as an additional source for surface sampling using adhesive tape.
Light colored toxic mold on paneling can be hard to see in ordinary lighting and requires careful inspection. But notice how the lighting shows
that this paneling is buckled. I'd suspect that it has been exposed to high moisture if not water, and that there is risk of hidden mold on the
cavity side of this material. Further inspection was needed.
Aiming a light or flashlight at roughly right angles to a surface means most of the light rays bouncing back to your eye are coming off
that surface at the same angle - the light will have trouble showing the profile or edges of light-colored or other small particles.
Aiming
a light or flashlight along the surface means that some of the light rays are bounced off of the profiles or sides of small particles
on that surface, making them easier to see. I'm simplifying the physics of light a bit but you can see the point of these illustrations of finding
hard-to-spot light colored mold on a building surface.
Even dust, or any other surface irregularities show up better with this method of
inspection. we have used this method of oblique light direction to spot drywall nails as a quick way to find a wall stud when hanging a picture.)
For our longer article with more photos and advice on how to use lighting and how to aim a flashlight to spot hard to see mold,
read Mold Detection - using a flashlight to find mold - proper use of a flashlight can help spot mold on paneling and other building surfaces.
Another example of use of oblique lighting to find building defects is illustrated at PLASTER BULGES & PILLOWS.
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Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
Kansas State University, department of plant pathology, extension plant pathology web page on wheat rust fungus: see http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Leaf%20Rust.asp
"A Brief Guide to Mold, Moisture, and Your Home",
U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
Allergen Tests in Buildings advice about how to test, what to look for, in evaluating the level of dog, cat, or other animal allergens in a building
"IgG Food Allergy Testing by ELISA/EIA, What do they really tell us?" Sheryl B. Miller, MT (ASCP), PhD, Clinical Laboratory Director, Bastyr University Natural Health Clinic - ELISA testing accuracy: Here is an example of Miller's critique of ELISA
http://www.betterhealthusa.com/public/282.cfm - Townsend Letter for Doctors and Patients
The critique included in that article raises compelling questions about IgG testing assays, which prompts our interest in actually screening for the presence of high levels of particles that could carry allergens - dog dander or cat dander in the case at hand.
http://www.tldp.com/issue/174/IgG%20Food%20Allergy.html contains similar criticism in another venue but interestingly by the same author, Sheryl Miller. Sheryl Miller, MT (ASCP), PhD, is an Immunologist and Associate Professor of Basic and Medical Sciences at Bastyr University in Bothell, Washington. She is also the Laboratory Director of the Bastyr Natural Health Clinic Laboratory.
Allergens: Testing for the level of exposure to animal allergens is discussed at http://www.animalhealthchannel.com/animalallergy/diagnosis.shtml (lab animal exposure study is interesting because it involves a higher exposure level in some cases
Allergens: WebMD discusses allergy tests for humans at webmd.com/allergies/allergy-tests
Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.
Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice
Rodent control issues, including dander, fecal, and urine contamination of Buildings and Building insulation are discussed at our
Associations: Sick House, Sick Building, SBS - Air Quality, Government, Private Associations and Information Resources
Atlas of Clinical Fungi, 2nd Ed., GS deHoog, J Guarro, J Gene, & MJ Figueras, Centraalbureau voor Schimmelcultures, Universitat Rovira I Virgili, 2000, ISBN 90-70351-43-9 (you can buy this book at Amazon)
Atlas of Indoor Mold, Online Clinical Mold Atlas, Toxins, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)
Black Mold that is Harmless Photos of recognizable, usually harmless black mold on wood, bluestain, ceratocystis, ophistoma
Building Floods: quick steps after a building flood or plumbing leak can prevent costly mold contamination
Classes of Mold: what types of cosmetic, allergenic, or toxic mold are a problem? Can mold be cleaned-up successfully?
"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
"Disease Prevention Program for Certain Vegetable Crops," David B. Langston, Jr., Extension Plant Pathologist - Vegetables, University of Georgia (PDF document) original source: www.reeis.usda.gov/web/crisprojectpages/209797.html
"Disease Prevention in Home Vegetable Gardens,"
Patricia Donald,
Department of Plant Microbiology and Pathology,
Lewis Jett
Department of Horticulture, University of Missouri Extension - extension.missouri.edu/publications/DisplayPub.aspx?P=G6202
Fifth Kingdom, Bryce Kendrick, ISBN13: 9781585100224, is available from the InspectAPedia online bookstore - we recommend the CD-ROM version of this book. This 3rd/edition is a compact but comprehensive encyclopedia of all things mycological. Every aspect of the fungi, from aflatoxin to zppspores, with an accessible blend of verve and wit. The 24 chapters are filled with up-to-date information of classification, yeast, lichens, spore dispersal, allergies, ecology, genetics, plant pathology, predatory fungi, biological control, mutualistic symbioses with animals and plants, fungi as food, food spoilage and mycotoxins.
OTHER IAQ ISSUES: How To Find and Address Other Indoor Air or Indoor Environment Contaminants Besides Mold
Mold or allergens may not be the only or even the main indoor environmental contaminant. Don't let media attention to mold
cause so much enviro-scare fear that other, possibly more urgent hazards go un-addressed.
Ozone Warnings - Use of Ozone as a "mold"
remedy is ineffective and may be dangerous.
Pet control - if you can't say goodbye to your bird, cat, dog, guinea pig, hamster, tropical fish, then limit the
areas they occupy and limit the airflow from that area to sleeping or other areas of the building, use allergenic
bedding, eliminate wall-to-wall carpeting, improve housecleaning including use of a HEPA-rated vacuum cleaner. For more details
see our article Dog, Cat, and Other Animal Dander - Information for Asthmatics and Indoor Air Quality
Rodents, Mice, Squirrel Control - I find high levels of mouse and rodent dander, fecal dust, and urine-contaminated dust in some buildings,
and high levels of these materials in building insulation in those locations. If you have a mouse problem, particularly if mice and their waste (fecals or urine) are contaminating
the building HVAC or building insulation, may need both steps to clean up or remove infected materials and steps to stop an ongoing
rodent problem. If squirrels are a problem, the cleanup needs to include closing off entry openings into the building. Get some
help from a licensed pest control expert.
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