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ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY
MOLD: A COMPLETE GUIDE to TEST CLEAN PREVENT
ACCEPTABLE MOLD LEVEL
ACCURACY OF VARIOUS MOLD TEST METHODS
ACCURACY vs PRECISION of MEASUREMENTS
ACTION GUIDE - WHAT TO DO ABOUT INDOOR MOLD
AGE of MOLD - Old is the Mold?
AIR TEST FOR MOLD: ACCURACY
AIR TEST SAMPLING CASSETTE STUDY
AIRBORNE MOLD COUNT NUMBER GUIDE
ALLERGEN TESTS for buildings
BASEMENT MOLD WATER IMPACT
BIBLIOGAPHY for ENVIRONMENTAL HEALTH, MOLD, IAQ
BOD WASTEWATER TEST
BLACK MOLD, HARMLESS COSMETIC
BLACK MOLD, TOXIC & ALLERGENIC
BOOK MOLD, Moldy Book Cleaning
BOOKSTORE - ENVIRONMENTAL
BROWN HAIRY BATHROOM MOLD
CAR MOLD CONTAMINATION
CARBON DIOXIDE - CO2
CARBON MONOXIDE - CO
CARBON MONOXIDE WARNING
CARPET MOLD CONTAMINATION
CARPET PADDING ASBESTOS, MOLD, ODORS
CARPET FUNGICIDAL SPRAY
CARPET TEST PROCEDURE
CARPETING & INDOOR AIR QUALITY
CHAIN OF CUSTODY - TEST SAMPLE
CLEARANCE INSPECTIONS - MOLD CLEANUP
CRAWLSPACE MOLD ADVICE
DIRT FLOOR MOLD CONTAMINATION
DUCT SYSTEM & DUCT DEFECTS
DUST ANALYSIS for FIBERGLASS
DUST SAMPLING PROCEDURE
EFFLORESCENCE, Salts & White / Brown Deposits
EMERGENCY RESPONSE, IAQ, GAS, MOLD
FEAR of MOLD - MYCOPHOBIA
Fiberboard Insulation Sheathing Mold
FIBERGLASS INSULATION MOLD
FIBERGLASS PARTICLE CONTAMINATION TEST
FIND MOLD, ESSENTIAL STEPS
FIND MOLD in buildings, HOW TO
FIRE DAMAGE vs MOLD DAMAGE
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FUNGICIDAL SPRAY & SEALANT USE GUIDE
HIDDEN MOLD, HOW TO FIND
HUMIDITY CONTROL TO PREVENT MOLD
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INDOOR AIR QUALITY METHODS COMPARED
LAB PROCEDURES MICROSCOPE TECHNIQUES
MEDIA BLASTING for MOLD REMOVAL
METHANE GAS SOURCES
MICROSCOPE DIGITAL PHOTOGRAPHY
MILDEW in BUILDINGS ?
MILDEW ERRORS - MOLD PHOTOS
MILDEW REMOVAL & PREVENTION
MOISTURE CONTROL in BUILDINGS
MOLD: A COMPLETE GUIDE TO MOLD
MOLD ACTION GUIDE - WHAT TO DO ABOUT MOLD
MOLD APPEARANCE - WHAT MOLD LOOKS LIKE
MOLD CLEANERS - WHAT TO USE
MOLD CLEANUP GUIDE- HOW TO GET RID OF MOLD
MOLD CLEARANCE INSPECTIONS
MOLD COUNT NUMBER GUIDE
MOLD CONSULTANTS / INSPECTORS
MOLD CULTURE TEST KIT VALIDITY
MOLD DETECTION & INSPECTION GUIDE
MOLD or INDOOR AIR EMERGENCY RESPONSE
MOLD EXPERT, WHEN TO HIRE
MOLD LEVEL IN AIR, VALIDITY
MOLD ODORS, MUSTY SMELLS
MOLD PREVENTION GUIDE
MOLD RELATED ILLNESS GUIDE
MOLD SAFETY WARNINGS
MOLD SPRAYS, SEALANTS, PAINTS
TEST KITS for DUST, MOLD, PARTICLE TESTS
MOLD TEST METHODS, ACCURACY
MOLD TEST vs. PROBLEM DIAGNOSIS
Are Mold Test Kits Useful?
MOLD TEST PROCEDURES
MOLD TEST REASONS
1. Save Money if it's Just Cosmetic Mold
2. Mold Related Illness
3. Mold Cleanup Data baseline
MOLD TESTING METHOD VALIDITY
Shortcomings of air sampling
Mold in Air: Quantitative Analysis
Tape sampling for mold
Determination of mold genera
Determination of mold species
Shortcomings of tape sampling
Shortcomings of surface and carpet vacuuming
Vacuuming building cavities
Vacuuming exposed insulation
Shortcomings of vacuuming insulation
Cultures to "Test for Mold"
Shortcomings of culturing
Shortcomings of swab sampling
PCR methods for Mold Identification
MOLD TESTING SERVICES
MOLD TOXICITY VARIATION
MSDS Material Safety Data Sheets
MVOCs & MOLDY MUSTY ODORS
MYCOPHOBIA, STAINS MISTAKEN for MOLD
MYCOTOXIN EFFECTS of MOLD EXPOSURE
ODORS GASES SMELLS, DIAGNOSIS & CURE
OZONE for MOLD OR ODORS
RENTERS GUIDE TO MOLD & IAQ
ROBIGUS & Wheat Rust Fungus
SICK HOUSE IAQ QUESTIONNAIRE
SLIDE PREPARATION, MICROSCOPE
SMELL PATCH TEST to Track Down Odors
STAIN & BIODETERIORATION AGENT CATALOG
STAIN DIAGNOSIS on BUILDING INTERIORS
STAINS on INDOOR SURFACES: PHOTO GUIDE
STAINS & Thermal Tracking
TECHNICAL & LAB PROCEDURES
TRAPPED MOLD BETWEEN WOOD SURFACES
Urea Formaldehyde Foam Insulation UFFI
URETHANE FOAM Deterioration, Outgassing
UV LIGHT BLACK LIGHT USES
VAPOR BARRIERS & CONDENSATION in BUILDINGS
VENTILATION in BUILDINGS
VINYL CHLORIDE HEALTH INFO
VINYL Siding or PLASTIC Window ODORS
Volatile Organic Compounds VOCs
WALL CONSTRUCTION BARRIER vs CAVITY
WATER BARRIERS, EXTERIOR BUILDING
WATER ENTRY in buildings
World Trade Center Collapse Dust Photos
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.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
15th Annual North Carolina/South Carolina
This discussion of the usefulness and validity of mold tests is divided into two main topics:
Our MOLD INFORMATION CENTER includes more broad discussions of the overall approach to building investigation, as do many expert references cited at that web. For a more comprehensive collection information about mold test methods see INDOOR AIR QUALITY METHODS COMPARED. For more on "mold classes" (Cosmetic mold vs. allergenic mold vs. toxic or pathogenic mold) see MOLD CLASSES, HAZARD LEVELS and more references such as a Mold Action Guide are at the end of this document.
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:
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/sickhouse/cultures.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
Because mold test validity and mold test accuracy are often confused, readers should also see ACCURACY OF VARIOUS MOLD TEST METHODS. People who need to conduct mold inspection and testing indoors should see MOLD TEST PROCEDURES and TECHNICAL & LAB PROCEDURES. MOLD TESTING SERVICES lists mold testing professionals.
Frequently Asked Questions (FAQs)
Questions & answers or comments about the difference between a simple mold test and more accurate procedures to find out if there is a mold contamination problem in a building.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.