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ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY
MOLD: A COMPLETE GUIDE to TEST CLEAN PREVENT
ACTIVITY of MOLD in BUILDINGS
AGE of MOLD - Old is the Mold?
AIR CLEANER PURIFIER TYPES
AIR FILTERS for HVAC SYSTEMS
AIR TEST SAMPLING CASSETTE STUDY
AIRBORNE MOLD COUNT NUMBER GUIDE
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ALLERGEN TESTS for BUILDINGS
BROWN HAIRY BATHROOM MOLD
BIBLIOGAPHY for ENVIRONMENTAL HEALTH, MOLD, IAQ
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BLEACHING MOLD, Advice about
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BOOKSTORE - ENVIRONMENTAL
CACTUS FUNGI / MOLD
CAR MOLD CONTAMINATION
CARPET DUST IDENTIFICATION
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CARPET & other STAIN TESTS
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CARPETING & INDOOR AIR QUALITY
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DIRECTORY of MOLD / ENVIRONMENTAL EXPERTS
DIRT FLOOR MOLD CONTAMINATION
Disinfecting Buildings with Bleach
DO-IT-YOURSELF MOLD CLEANUP WARNINGS
DUST ANALYSIS for FIBERGLASS
DUST, HVAC CONTAMINATION STUDY
EFFLORESCENCE, Salts & White / Brown Deposits
FEAR of MOLD - MYCOPHOBIA
Fiberboard Insulation Sheathing Mold
FIBERGLASS INSULATION MOLD
FIND MOLD, ESSENTIAL STEPS
MOLD in BUILDINGS
FIRE DAMAGE vs MOLD DAMAGE
FLOODS IN BUILDINGS-mold
FOXING STAINS on books & papers
FUNGICIDAL SPRAY & SEALANT USE GUIDE
GAS DETECTION INSTRUMENTS
GAS EXPOSURE EFFECTS, TOXIC
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GAS TEST PROCEDURES
HOUSE DUST ANALYSIS
HOUSE DUST COMPONENTS
HUMIDITY CONTROL & TARGETS INDOORS
LAB PROCEDURES MICROSCOPE TECHNIQUES
LIGHT, GUIDE to FORENSIC USE
MEDIA BLASTING for MOLD REMOVAL
METHANE GAS SOURCES
MICROSCOPE DIGITAL PHOTOGRAPHY
MEDIA BLASTING for MOLD REMOVAL
METHANE GAS SOURCES
MICROSCOPE DIGITAL PHOTOGRAPHY
MILDEW ERRORS, IT's MOLD
MILDEW REMOVAL & PREVENTION
MOISTURE CONTROL in BUILDINGS
MOLD: A COMPLETE GUIDE TO MOLD
MOLD EXPERT, WHEN TO HIRE
MVOCs & MOLDY MUSTY ODORS
MYCOPHOBIA, STAINS MISTAKEN for MOLD
MYCOTOXIN EFFECTS of MOLD EXPOSURE
ODORS GASES SMELLS, DIAGNOSIS & CURE
RENTERS GUIDE TO MOLD & IAQ
ROBIGUS & Wheat Rust Fungus
SMELL PATCH TEST to Track Down Odors
STAINS on & in BUILDINGS, CAUSES & CURES
THERMAL IMAGING MOLD SCANS
TRAPPED MOLD BETWEEN WOOD SURFACES
UV LIGHT BLACK LIGHT USES
VAPOR BARRIERS & CONDENSATION
VENTILATION in BUILDINGS
Volatile Organic Compounds VOCs
WATER ENTRY in buildings
Mold test vs. mold contamination detection: Here we distinguish between tests to identify mold in a building and procedures to determine whether or not there is a mold contamination problem in a building. Following that distinction we continue by listing the specific reasons to test for mold or cases when mold testing is appropriate and useful.
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This discussion of the usefulness and validity of mold tests is divided into two main topics:
Mold testing discussion can be divided into two main topics, the first of which is discussed in this paper.
We are "making up" this temporary distinction to make clear an important point.
Mold Testing a building for the presence or absence of a problematic level of mold is unreliable if by "testing" one means a simple air test, an arbitrary surface or vacuum test, a swab test, or any culture method used alone and without a careful and complete inspection of the property. In particular, failure to detect problem levels of problem mold with an air, culture, swab, PCR or similar test (used alone) is not sufficient to conclude that there is no problem.
1. Airborne particle levels vary widely over short time intervals. What's in the air in a building varies enormously, possibly by a factor of thousands, over just a few minutes, depending on things like the level of activity, mechanical disturbance of dust, fans being turned on or off, hot air heat or central air being on or off, and more subtle changes in humidity, etc.
2. Cultures whether from a "home test kit" culture plate or a swab are unreliable as a characterization of presence or absence of mold because first, only about 10% of all of the 1.5 million mold species on earth will grow in any culture under any condition, second because what grows on a particular culture may be what likes that culture not what is the dominant problem, and third, because accurate speciation of some of our problem groups such as Penicillium sp. and Aspergillus sp. require arduous multiple cultures under very controlled conditions for reliable results.
3. PCR tests are highly accurate in identifying individual molds, if you know what you're looking for. PCR is not reliable as a broad spectrum scan to find what's in a building.
Mold Problem Identification, as we are speaking here, is an important part of a building investigation for mold (or other allergen) problems.
By this we mean, an investigator should be charged to identify the presence of problematic mold, including no less than the following: first, the evidence that problematic levels of mold are present and that the predominant genera/species are ones which can be expected to be toxic or highly allergenic; second, the evidence that a large problem reservoir exists; third, the location(s) of the problem reservoir; fourth, the underlying causes for the presence of the problem reservoir. This information permits preparation of a remediation plan to specify the cleanup needed and the building repairs needed to avoid simply producing more mold.
Key in a Mold Problem Identification investigation is the actual visual examination of the building, its history, its leaks, and other physical evidence. As a part of such an investigation, samples are collected of visible mold to distinguish cosmetic from problematic material, and other samples might be collected to examine the level of moldy dust settled in building areas where mold is not present. Additional samples may be collected for comparison baselines such from outdoor areas or from non-complaint areas in the problem building.
A thorough building investigation will include sampling or "tests" to identify the presence of mold and to identify the dominant problem molds by genera and often species. By contrast, a quick and simple "mold test," particularly a random spot check, is of little value by itself: grabbing a 90 liter air sample or putting a settlement plate in a closet for an hour is not a reliable building characterization for mold, and a tape sample of the single square foot of mold in a building is unnecessary.
Clean up small areas without testing:
Some states define "small" as less than 30 sq.ft. of contiguous mold. Your own area may use a different criterion. Larger areas of non-cosmetic mold are likely to require work by a cleanup professional. If you think you need to hire someone, see "When to hire a professional" for more detailed help in deciding when and how to proceed.
Settlement plates, culture media, or swabs which are later cultured, used alone for building mold risk analysis are invalid methods which risk both false positive results (saying there's a problem when there is not) and false negative results (missing an important problem). More about this is in this article and you can read in greater depth at The Validity of Cultures. http://InspectAPedia.com/mold/Mold_Culture_Test_Validity.htm
What about other do-it-yourself tests? Amateur mold "testing" by a homeowner, using a tape lift of visible mold, perhaps with some good advice on where to look, might be an inexpensive way find out that the "black mold" on the floor joists is a "cosmetic-only" mold, thus avoiding the cost of a more expert professional building investigation/remediation.
However anyone using this approach should understand that it is incomplete and superficial: you might collect your sample from a spot which is not representative; you will not address the risk of hidden mold in building cavities; you will not have expert mold remediation advice; you will not have baseline data to support a later clearance test after cleanup, finally, you risk leaving another problem in the building. These warnings should be considered carefully where large areas of mold are already visible or at-risk occupants are involved.
Of the mold samples sent to our lab by owners who have had no collection advice, we find that "black molds" seem to be over-represented and we suspect these are often not the real problem in the building. The mold the owner sees may be simply the indicator of moldy conditions.
Lighter, harder-to see molds in the Penicillium sp. and Aspergillus sp. families, for example, are under-represented in owner-collected samples (based on our field experience and on our review of statistics of samples sent to Dr. J. Haines at the N.Y. State Museum for identification) because these genera are often more difficult to see.
Mold Test Accuracy vs Mold Test Validity
At DO IT YOURSELF MOLD CLEANUP we provide suggestions for a do-it-yourself cleanup of small areas of mold. At MOLD EXPERT, WHEN TO HIRE we provide guidelines to help decide when it is probably justified to bring in a mold expert to perform mold inspection and testing in a building.
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