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Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY
MOLD: A COMPLETE GUIDE to TEST CLEAN PREVENT
ACCEPTABLE MOLD LEVEL
ACCURACY vs PRECISION of MEASUREMENTS
ACTION GUIDE - WHAT TO DO ABOUT INDOOR MOLD
ACTIVITY of MOLD in BUILDINGS
AIR TEST FOR MOLD: ACCURACY
AIR TEST SAMPLING CASSETTE STUDY
AIRBORNE MOLD COUNT NUMBER GUIDE
AIRBORNE PARTICLE ANALYSIS METHODS
ALLERGEN TESTS for BUILDINGS
ALLERGENS in BUILDINGS, RECOGNIZING
ALLERGY & MOLD IAQ PRODUCTS
ALLERGY TESTS for PEOPLE
ALLERGY TEST ACCURACY
ASBESTOS IDENTIFICATION IN BUILDINGS
BASEMENT MOLD WATER IMPACT
BIBLIOGAPHY for ENVIRONMENTAL HEALTH, MOLD, IAQ
BIOGAS PRODUCTION & USE
BOD WASTEWATER TEST
BLACK MOLD, HARMLESS COSMETIC
BLACK MOLD, TOXIC & ALLERGENIC
BLEACHING MOLD, Advice about
BOOK MOLD, Moldy Book Cleaning
BOOKSTORE - ENVIRONMENTAL
BROWN HAIRY BATHROOM MOLD
CACTUS FUNGI / MOLD
CAR MOLD CONTAMINATION
CARPET DUST IDENTIFICATION
CARPET MOLD CONTAMINATION
CARPET PADDING ASBESTOS, MOLD, ODORS
CARPET STAIN DIAGNOSIS
CARPET & other STAIN TESTS
CARPET TEST PROCEDURE
CARPETING & INDOOR AIR QUALITY
CARPETING, SELECTION & INSTALLATION
CAT DANDER in BUILDINGS
CLEARANCE INSPECTIONS - MOLD CLEANUP
EFFLORESCENCE, Salts & White / Brown Deposits
FIBERGLASS INSULATION MOLD
FIND MOLD, ESSENTIAL STEPS
MOLD in BUILDINGS
FIRE DAMAGE vs MOLD DAMAGE
FLOODS & MOLD CLEAN/PREVENT
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOODS IN BUILDINGS-mold
FOXING STAINS on books & papers
FUNGICIDAL SPRAY & SEALANT USE GUIDE
GAS EXPOSURE EFFECTS, TOXIC
GAS DETECTION INSTRUMENTS
HOUSE DUST ANALYSIS
HOUSE DUST COMPONENTS
HOUSEWRAP AIR & VAPOR BARRIERS
HIDDEN MOLD, HOW TO FIND
HUMIDITY CONTROL & TARGETS INDOORS
INDOOR AIR HAZARDS TABLE
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INDOOR AIR QUALITY IMPROVEMENT GUIDE
INDOOR AIR QUALITY METHODS COMPARED
INSULATION INSPECTION & IMPROVEMENT
LAB PROCEDURES MICROSCOPE TECHNIQUES
LEAD POISONING HAZARDS GUIDE
Legionella Legionnaires' Disease
Legionella BACTERIA & HVAC Equipment
LIGHT, GUIDE to FORENSIC USE
GAS LP & NATURAL GAS SAFETY HAZARDS
MEDIA BLASTING for MOLD REMOVAL
METHANE GAS SOURCES
MICROSCOPE DIGITAL PHOTOGRAPHY
MILDEW in BUILDINGS ?
MILDEW ERRORS, IT's MOLD
MILDEW REMOVAL & PREVENTION
MOISTURE CONTROL in BUILDINGS
MOLD ACTION GUIDE - WHAT TO DO ABOUT MOLD
MOLD ACTIVITY in BUILDINGS
MOLD AGE - Old is the Mold?
MOLD APPEARANCE - WHAT MOLD LOOKS LIKE
MOLD APPEARANCE - STUFF THAT IS NOT MOLD
MOLD ATLAS & PARTICLES INDEX
MOLD by MICROSCOPE
MOLD CLASSES, HAZARD LEVELS
MOLD CLEANERS - WHAT TO USE
MOLD CLEANUP COMPANIES
MOLD CLEANUP, DO IT YOURSELF
MOLD CLEANUP GUIDE- HOW TO GET RID OF MOLD
MOLD CLEANUP - BLEACH
MOLD CLEANUP - HEALTH RISKS
MOLD CLEANUP - LIMITATIONS
MOLD CLEANUP - MISTAKES to AVOID
MOLD CLEANUP - MEDIA BLASTING
MOLD CLEANUP - SAFETY WARNINGS
MOLD CLEANUP - WOOD FLOORING
MOLD CLEANUP - WOOD FRAMING & PLYWOOD
MOLD CLEARANCE - POST-REMEDIATION INSPECTION
MOLD CONTAMINATION LEVELS, STANDARDS
MOLD DETECTION & INSPECTION GUIDE
MOLD DOCTORS - ENVIRONMENTAL MEDICINE
MOLD or INDOOR AIR EMERGENCY RESPONSE
MOLD EXPERT, WHEN TO HIRE
MOLD EXPOSURE, FOOD HAZARDS
MOLD EXPOSURE RISK LEVELS
MOLD EXPOSURE STANDARDS
MOLD on or in CARPETS
MOLD on DIRT FLOORS
MOLD FREQUENCY in BUILDINGS
MOLD GROWTH on SURFACES, PHOTOS
MOLD GROWTH on SURFACES, TABLE OF
MOLD INSPECTORS & MOLD TESTERS
MOLD INSPECTION HOME BUYERS GUIDE
MOLD INSPECTION SERVICE
MOLD INVESTIGATION PROCEDURE TIPS
MOLD INVESTIGATION REPORTS
MOLD KILLING GUIDE
MOLD LAB REPORTS
MOLD LEVEL REPORTS
MOLD LEVELS IN BUILDINGS
MOLD by MICROSCOPE
MOLD ODORS, MUSTY SMELLS
MOLD PREVENTION GUIDE
MOLD RELATED ILLNESS
MOLD SAFETY WARNINGS
MOLD SPRAYS, SEALANTS, PAINTS
TEST KITS for DUST, MOLD, PARTICLE TESTS
MOLD TEST METHODS, ACCURACY
MOLD TEST PROCEDURES
MOLD TEST REASONS
MOLD TEST SAMPLE POINT CHOICES
MOLD TESTING & SAMPLING MISTAKES
MOLD TESTING SERVICES
ODORS GASES SMELLS, DIAGNOSIS & CURE
PAINTS & COATINGS ODORS IN BUILDINGS
PARTICLE SIZES & IAQ
Particulates & Allergens Indoors
PESTICIDE EXPOSURE HAZARDS
PET ALLERGEN REMEDIES
PLASTIC CONTAINERS, TANKS, TYPES
PLASTIC Plexvent / Ultravent RECALL
PLASTIC ODORS-SCREENS, SIDING
PLUMBING SYSTEM ODORS
RENTERS GUIDE TO MOLD & IAQ
SICK HOUSE IAQ QUESTIONNAIRE
SEWAGE BACKUP, WHAT TO DO
STAIN DIAGNOSIS on BUILDING INTERIORS
STAINS on INDOOR SURFACES: PHOTO GUIDE
STAINS & Thermal Tracking
TECHNICAL & LAB PROCEDURES
TEST KITS for DUST, MOLD, PARTICLE TESTS
Thermal Expansion Cracking of Brick
THERMAL EXPANSION of HOT WATER
THERMAL EXPANSION of MATERIALS
THERMAL IMAGING, THERMOGRAPHY
THERMAL IMAGING MOLD SCANS
THERMAL MASS in BUILDINGS
THERMAL TRACKING & THERMAL BRIDGING
TRAPPED MOLD BETWEEN WOOD SURFACES
TRIM, INTERIOR INSTALLATION
TRUSS UPLIFT, ROOF
TRUSSES, Floor & Roof
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 Window PLASTIC ODORS
VOCs VOLATILE ORGANIC COMPOUNDS
WALL SIDING TRIM & FINISHES
WALL FINISHES INTERIOR
WALL CONSTRUCTION BARRIER vs CAVITY
WATER BARRIERS, EXTERIOR BUILDING
WATER ENTRY in buildings
WATER ODORS, CAUSE CURE
WORLD TRADE CENTER 9-11 DUST PHOTOS
What does building mold look like? Here is an online reference photo library of various kinds and colors of mold as it is found growing in buildings. These photos of mold on indoor building surfaces may help you recognize mold in buildings, recognize probably-cosmetic mold, and recognize stuff that is not mold and does not need to be tested. If you don't see information you want, ask us for it using the comments box at the end of this article.
Also see MOLD GROWTH on SURFACES, PHOTOS.
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Directories of 6 atlases or indices of building mold
Look closely when inspecting or collecting test samples of "toxic black mold" because often there are other molds, sometimes more harmful and more easily airborne mold species on the same surface, on the hidden side of the same surface of drywall, or nearby.
These include lighter colored genera/species of Aspergillus sp., Penicillium sp. etc. which are too often missed when investigators or building owners focus only on "black mold" testing.
But if this is a "tip of iceberg" clue of a larger hidden problem in the wall, or if it might be, further investigation, at least exploring the wall cavity, would be appropriate.
Black mold on rotting subfloor below a leaky sliding glass door - this "black mold" was Taeoniella rudus for which no medical issues have been reported - a wood rotting organism though.
An investigation of the source of outside leaks and extent of damage to the structure were needed at this building.
Black Stachybotrys chartarum black mold on wallpaper below a leaky window. The window had been left open more than once during rainy weather. We found that water was leaking into the wall cavity, not just behind the wallpaper.
Replacement of a small section of drywall, wall cavity insulation, and wallpaper were appropriate at this location where the first symptom was loose peeling wallpaper which exposed black mold.
Notice the funny black mold
growth pattern on the cavity side of the opposing drywall. This pattern maps the points of contact of the wall
insulation kraft paper with the drywall surface, and the movement of moisture and spreading mold growth on the wall
surface. It is characteristic of wall cavity mold and is different from the growth pattern of mold growing on a freely
exposed-to-air drywall surface.
The wall cut exposed a surprise point of water entry. Black mold was visible on the insulation kraft paper.
The problematic mold in this case was not visible but was found by a special sampling technique we used to examine the building insulation for Aspergillus sp. and Penicillium sp. (problem molds) in the fiberglass.
It was found to be highly contaminated and was determined to
be an active reservoir releasing high levels of airborne mold into the basement.
Our mold photo at above left shows black mold colonies growing among green mold colonies on a laundry room ceiling, covering both plastic ceiling tile material (around the plumbing pipes) and drywall. It is often the case that multiple mold genera/species may be growing in the same area, often on the same surface, and at times, on top of one another.
As we advised earlier, look closely when inspecting or collecting test samples of "toxic black mold" because often there are other molds, sometimes more harmful and more easily airborne mold species on the same surface, on the hidden side of the same surface of drywall, or nearby. In this building that was still wet at the time we took this photograph, the airborne level of Aspergillus sp. and Penicillium sp. (the green, gray, and light colored molds in the photo) was very high while the level of airborne Stachybotrys chartarum, Cladosporium sphaerospermum, and Nigrospora sp. (black molds found on these surfaces) was very low.
Our photo at above right shows black mold colonies as smaller "spots" growing on the painted surface of cloth covering asbestos pipe insulation.
Our black mold photos above show dense black fungal growth on drywall (black mold on Sheetrock™ type wall surfaces) in areas that have been very wet. The distinct top edge of mold growth may mark a flood water level or a discontinuity in the wall material, such as a tape joint in drywall that affected the moisture gradient in the wall and thus the mold growth pattern.
Close up Photographs of Black Mold on Building Surfaces
Here we begin to "zoom in for a closer look at dense black mold growth on indoor building surfaces in a wet basement. Notice that the mold growth on drywall and often on other surfaces includes a family of circular growth patterns (upper area of photo at above right) until the mold growth has expanded to form a solid black covering (left wall of photo at left and lower wall of black mold in photo at right).
Our photo at above left shows black mold colonies as individual rounded "rings" on the cavity side of drywall on a building crawl area wall. The black mold photo at right shows how dense black mold may be hidden from view behind wall baseboard trim (removed for this picture) in a building that has suffered wet floors.
Black mold growth on furniture is obvious in these two photographs, of a mold on a leatherette surface (left) and on an upholstered chair (right).
In our photo at above left we see black mold and other mold growths on the kraft paper facing of fiberglass building insulation. Our black mold photo at above right shows that mold colonies do not always grow in the neat round ring-like colonies shown in some our earlier photographs.
Here we start to zoom in our photographs of black mold on building surfaces to show what mold colonies look like on close inspection in-situ. At left is mold on water stained drywall in a basement utility area. At right are small mold colonies that have appeared on a kitchen ceiling in just a few days after a heating system leak led to high indoor moisture and humidity levels.
Much more closely we can examine an individual black mold colony on a painted drywall ceiling (above left). In the microscope at 1000x we can see individual spores of Stachybotrys chartarum - a well known black mold that is often found on indoor building surfaces.
Other Examples of What Mold Looks Like in Buildings
Question: Is this stuff on my ceiling mold?
I just moved into a rental trailer and it had a strong musty smell. I thought, maybe it hasn't been aired out. well, after two days of doors and windows open, it still smells. I found the brown discoloration on the ceiling in the kitchen cabinets. Is it mold? Thank you, - L.B.
Reply: maybe not, but those water stains mean there may be a significant risk of hidden mold indoors
Your photo shows some heavy staining on what looks like suspended ceiling tiles. The brown stains themselves may not be mold but rather brown materials carried by roof leaks into the ceiling structure. Older trailers and mobile homes often have leaky roofs.
It looks as if water has also run down the wall surface and quite likely the wall cavity of the home below those same stains.
In this case the stains you see might not be mold but they do indicate that there is a high risk of mold in this home. Here are spots where I'd suspect a more hidden but possibly larger problem reservoir of mold when we see leak stains like yours:
I suggest having someone take a look at the insulation and floor condition in the area of leakage from below the mobile home. If that area is wet and damaged you can pretty much expect that there is hidden damage and mold in the ceiling and wall above.
If the damage is not so extensive that immediate major repairs to the structure are needed, but if there appears to be anything greater than 30 sq.ft. of moldy material, professional cleaning and repairs are needed. And the cleaning and repair work cannot be concluded before the leaks are fixed. Also see ACTION GUIDE - WHAT TO DO ABOUT INDOOR MOLD.
Watch out: in some mobile homes where there has been chronic leakage we have seen floors that were badly deteriorated and even collapse.
Finally, because you are renting, you will want to see our mold advice for renters: RENTERS & TENANTS: MOLD ADVICE
Online Mold & Particle Identification Aids at InspectAPedia.com
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