Photographs of Stuff that is Not Mold: white fluffy crystalline deposits, black stains, yellow stains, & other diagnostic photographs
InspectAPedia® -
Photos & text aid identifying indoor stains mistaken for toxic mold
How to identify white stains, white fluffy material, white crystalline material on building walls & in basements and crawl spaces -mineral efflorescence is not mold
How to identify amber material in attics as Wood sap; identify foam insulation in buildings
How to recognize black stains as thermal tracking or soot
BBMS: BasketBall Mold Syndrome: why do we think old conditions are "new" on buildings?
How to identify stains on soiled walls/trim caused by animals
How to recognize cosmetic or harmless black (or other color) mold & Links to photos of stuff that is bad mold
Questions & answers about how to identify stuff in buildings that is not mold but may be mistaken for it. Stains, deposits, growths, etc.
This article describes indoor stains and deposits that are not building mold. When investigating a building for a mold problem, you can save mold test costs by learning how to recognize Stuff that is Not Mold or is only Harmless Mold but may be mistaken for more serious contamination
- save your money. For photos of stuff that is indeed mold contamination in buildings, see MOLD APPEARANCE - WHAT MOLD LOOKS LIKE. If you don't see information you want, ask us for it using the comments box on this page.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers nor with topics or services discussed at this website.
Because people sometimes send "mold test"
samples to our lab that really should not have been collected, much
less looked-at, I provide this library of photographs of things that are "not mold" and don't need to be tested. These are substances that you can easily learn to recognize in buildings.
Save your mold test money, and increase the accuracy
of your mold contamination inspection or test for toxic or allergenic mold in buildings: review
these items to learn recognize non-fungal materials or even possibly harmless cosmetic "black mold" often mistaken for "toxic fungal growth."
HARMLESS INDOOR PARTICLES - Examples of scary-looking, usually harmless indoor stuff that is sometimes mistaken for mold
So many people have called me to look at things that are not mold that I'm offering some photo tips below. Don't hire an environmental
consultant if your only concern is the stuff you see here and if there are no health or air quality complaints. Save your money, don't bother testing
the things you see below.
Finding "not mold" material in a building does not mean that there is no mold or allergen problem. Even relatively harmless house dust collected on a surface and sent to our lab as a mold screening test can contain a surprising amount of problematic mold spores
if the building has a mold problem.
More important for mold testing, right in among an old colony of harmless
cosmetic black mold I've on often found hard-to-see Aspergillus sp. or Penicillium sp. mold that grew there much after the original black mold deposit. Judgment and common sense are needed. Nonetheless, the examples
below are unambiguous and should not be sampled for mold testing.
Review This List & These Photographs of Stains or Stuff in Buildings that Are Not Mold or Are Harmless Cosmetic Indoor Mold
In this article on things that are not mold, do not require mold testing, but which may still help diagnose building conditions and history, we'll discuss, describe, and provide photographs of some common items that are sometimes mistaken for mold in buildings:
Animal Stains or marks on building interior walls caused by dogs, cats or other animal stains on building carpets, floors, walls, doors, trim: how to diagnose and remove pet stains and odors.
Black cosmetic mold - such as black stains due to Ceratocystis or Ophistoma fungi that were on framing lumber at the time of construction may be completely harmless, cosmetic only. At Black cosmetic mold we discuss some simple but reliable ways to identify cosmetic molds that have been present since time of building construction. In our companion article, Recognize Harmless Black Mold, we discuss two specific harmless, cosmetic black molds commonly found on framing lumber.
Efflorescence & White or Brown Stuff white, tan, crystalline or bubbly, tan, or other-colored mineral salts on foundations and masonry walls - white fluffy stuff or white crystalline stuff often found on building walls may not be mold at all, though it is an indicator of problem leaks, moisture, dampness. Efflorescence describes white fluffy crystalline material that is not mold. White Mold describes actual white or light colored mold in buildings.
House dust which may or may not contain mold, allergens, or other problems
Sprayed foam insulation- that looks a little like certain fungal growths in crawl spaces or other building areas, usually yellow or white in color
Wood sap- clear or crystalline tan or yellow droplets found on wood framing, often in attics
Look for Efflorescence - Mineral Deposits (not mold) on Building Foundations and Masonry Walls
What about white fluffy "growth" or stuff on walls, particularly masonry walls? You may be looking at efflorescence - which is not mold.
What about brown or even reddish or darker bubbly stuff that seems to be "growing" on masonry or plaster walls? You may be looking at efflorescence - which is not mold.
Be sure to go to Efflorescence & white or brown deposits to review our photos and text on how to recognize mineral efflorescence that is likely to be found on concrete block, stone, brick walls, foundations, and chimneys.
This white fluffy material is efflorescence, a crystalline mineral salt left
behind as moisture comes through the wall and evaporates into the building interior.
Brownish or reddish bubbly efflorescence and dirt deposits on walls may be a mix of mineral efflorescence and other salts and debris left behind as water or moisture pass through building ceilings or walls.
Efflorescence is not mold, though it is an indicator of wet conditions that could contribute to a mold problem somewhere in the building.
In sum, although efflorescence is not mold, it often indicates wet conditions that cause problem mold growth elsewhere in the same building. You'll need to identify the sources of moisture or leaks and correct them, and depending on other building air quality complaints or health concerns it may be appropriate to inspect and screen the building for problem mold or other moisture or water-related problems.
How to Identify Wood Sap Crystals on Building Framing
What about those clear or opaque spherical brown blobs we see on rafters in attics? Is that toxic brown mold? Probably not. Take a look at this photograph.
This is not mold, it's sap crystals that have been extruded from the wood due to high attic temperatures. We see more of this sap staining when the wood used for framing was not kiln dried before construction.
Mistaking sprayed foam for mold growth in buildings
Some mold-suspect material in buildings is easily determined to be spray foam insulation.
Sprayed icynene foam insulation is not mold either. Though we sometimes find fungal growth in buildings that looks a lot like this substance, it would be very odd for it to appear so extensively and so uniformly as the foam insulation shown in this photo. For more information about foam spray insulation such as Icynene foam, see How to Identify Icynene Foam Insulation and for an older foam insulating product see How to Identify UFFI Foam Insulation.
To compare actual mold growth with crawlspace foam insulation see this photograph of yellow mold growth taken from a rotting wood truss in a wet crawl space.
You'll see it looks a bit like the sprayed foam insulation shown on this page. But actual yellow mold growth on wood won't be found in a continuous blanket such as shown in our photograph of icynene foam on this page.
See INSULATION INSPECTION & IMPROVEMENT for details about foam and other building insulation types; see FIBERGLASS HAZARDS for a discussion of mold problems in fiberglass insulation; see Mold On Foam Insulation for a discussion of when and why we find mold growth on foam insulating materials like foam board and air handler foam insulating board.
How to recognize black stains that are thermal tracking or soot marks, not mold in buildings
Thermal tracking or soot tracking may be found where moisture condenses on cool building surfaces. Warm moisture-laden air
touches the cooler surface of a building wall or ceiling, giving up some of its moisture to the surface as condensation.
As air moves
through the building, typically up walls and across ceilings, debris in the air, particularly soot such as that left by burning
scented candles, adheres more to the damp surfaces than to others, leaving black marks or "tracks."
In a conventionally-framed
wood structure, wall and ceiling framing is typically on 16" or 24" centers. The wall or ceiling will be cooler where the
framing is located than will be the spaces which are not touched by framing and which, perhaps, are insulated. So if you see
black streaks up the building wall in a regular 16" or 24" pattern, particularly on cooler exterior walls but potentially anywhere,
it may be thermal tracking.
If you have frequent fireplace fires, cooking, or if you burn scented candles, if people smoke in your home, or if your oil-fired or gas-fired
heating system is not working properly, the added soot particle load in the building air is not only a health concern (soot and potentially lead), it also will mark the building surfaces in this characteristic
pattern.
Basketball Mold Syndrome (BBMS): How Old, Pre-Existing Building Conditions Can Be Perceived as Brand New and Threatening
BBMS is a term we coined for the phenomenon which describes an observer who is certain that a condition s/he has recently seen is a new condition even though solid forensic evidence shows that the condition is long-standing.
BBMS occurs when a person who has (other) reasons to be anxious about health or structural or safety conditions in a building (or any other condition where BBMS may apply) observes some mark, material, or substance for the first time. In other words, the condition or clue, mark, or substance was there before, but the person had no reason to attend, recognize, and consider it.
What Conditions Lead to BasketBall Mold Syndrome?
BBMS occurs most often (in our experience) where health concerns are present and people have become worried about mold contamination, or where structural concerns are present and people have become worried about cracks, stains, or possible indications of building damage.
Basketball print mold: A client was certain that a large collection of round black speckled marks on his garage ceiling were toxic mold, that the marks were growing in size, and that they had not been there when he purchased the home a few years before.
During a mold investigation we had seen and rapidly discounted the significance of these marks, preferring to follow water leaks and moisture to an actual building problem. To an experienced eye it was immediately obvious that the marks had been made by a basketball which someone had bounced against walls and ceilings.
It is important to realize that a stain or mark may have been in place but un-noticed for a long time on a building surface.
In its form of black on white on the garage ceiling the stain pattern was a bit hard to see. We used this trick of reversing black and white in the lab computer, making the basketball characteristic surface pattern of the ceiling marks which we sampled quite obvious.
We explain why this confusion about building clues and mold risk happens in a separate page: please see BASKETBALL MOLD SYNDROME - BBMS
THERMAL TRACKING STAINS for
a more detailed discussion of recognizing and diagnosing indoor stains on walls and ceilings, and for tips for using indoor stains
to diagnose a variety of building problems and safety concerns.
Black stains from animals for examples of animal stains that are sometimes mistaken for mold in buildings.
FOUNDATION DIAGNOSISfor examples of procedures used to diagnose and evaluate foundation wall and slab cracks and movement.
MOLD INFORMATION CENTER for guidance on what to do about mold and other indoor air quality issues
Cosmetic vs. Harmful Mold: Can Mold Make You Sick? Fear of Mold - Mycophobia - Can Lead to Unnecessary Expense
How to recognize black stains on indoor walls and trim caused by pets, not mold
With a little thought we can easily distinguish pet stains on drywall from thermal tracking by the stain pattern and location as well as other details such as the absence of a heat source, or the identification of a location where we'd expect a pet to rest.
Similarly we can identify black stains on walls where people's heads rested while sitting on furniture or in bed (see photo link just below).
Indoor House Dust Analysis Distinguishes Common from Problematic Mold and Other Particles
Killer House Dust from an HVAC system which turned out to be cotton and other
carpet fibers having nothing to do with the Heating or Cooling equipment was discussed at our Fear of Mold WebLog or "Blog" where we periodically post results of interesting forensic investigations.
House dust might be a contributor to building air quality complaints IF the dust has high levels of problem particles such as mold, dust mite fecals, pollen, sub-micron particulate debris, bacterial contaminants, pet hair, mouse dander or fecal dust, and similar particles.
The most common ingredients in house-dust in a healthy home are:
fabric fibers
human skin cells
starch granules, often from cooking and from bath products
pet dander and pet hair, especially if pets live in the home
non-fungal granular debris such as road dirt or soil particles
at lower levels: common outdoor biological particles such as pollen and mold spores are present but generally at a lower level than outdoors (except when the windows are open), and the mix of these particles will be more heterogeneous than when mold spores appear indoors from an indoor mold reservoir; we also may find certain outdoor mold spores only as individuals (such as Penicillium sp.) while if that same mold were growing indoors we may find it occurring as spore chains.
Some black mold in buildings arrived on the framing lumber and is harmless both to humans and to the building materials on which it is found.
Often a visual inspection for certain clues (discussed below) can make you very confident of when mold appeared on lumber and what sort it probably is.
We discuss how to recognize and what to do about harmless mold, harmless black mold, and cosmetic molds in our article:HARMLESS COSMETIC MOLD
Make sure that the obvious harmless "black mold" you see (such as shown in the photograph at left) is the only mold growth found.
So what does mold look like on or in a building?
Be sure to see our full article: WHAT MOLD LOOKS LIKE
that has photographs and descriptions of what real mold looks like inside a building.
But
be careful, some of the most problematic common indoor molds, the Aspergillus sp. and Penicillium group can be very light in color and hard to see
on building surfaces.
Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
Additional technical contributors & reference sources for this article are listed below.
Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
MOLD ATLAS & PARTICLES INDEX, Pathogens, Allergens and Other Indoor Particles - actual and possible medical health effects of Mold (separate online document)
MOLD GROWTH ON SURFACES, PHOTOS Photos of what mold looks like in buildings, organized by mold growth on various kinds of building surfaces and contents or items found in buildings. Mold in situ. MOLD GROWTH on SURFACES, TABLE OF, Summary table of what mold genera/species are frequently found on various building surfaces and materials
MOLD BY MICROSCOPE Mold under the microscope - photo identification of the most common indoor molds found in buildings
Contact Us to suggest changes and additions to these online mold identification guides
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
US EPA - Mold Remediation in Schools and Commercial Building [Copy on file at /sickhouse/EPA_Mold_Remediation_in_Schools.pdf ] - US EPA
US EPA - Una Breva Guia a Moho - Hongo [Copy on file as /sickhouse/EPA_Moho_Guia_sp.pdf - en Espanol
Allergies, Allergens, Allergy Testing in Buildings - References & Products
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) - The Atlas of Clinical Fungi is also available on CD ROM
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.
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