InterNACHI Certified Mold Inspector

Which mold genus is commonly known as 'black mold' and is strongly associated with chronic moisture damage on cellulose-rich materials such as drywall and wood?

• ACladosporium
• BAspergillus
• CStachybotrys chartarum
• DPenicillium

Which mold genus includes Aspergillus fumigatus, a thermotolerant species of particular concern to immunocompromised patients?

• ACladosporium
• BAspergillus
• CStachybotrys
• DAlternaria

On a non-viable spore-trap lab report, why are Aspergillus and Penicillium typically reported together as 'Aspergillus/Penicillium-like'?

• AThe two genera are biologically identical
• BTheir spores are morphologically indistinguishable by direct microscopy on spore traps
• CLab regulations require the combined category
• DOnly Aspergillus is regulated

Cladosporium is the MOST commonly identified mold in:

• ASealed building cavities with no moisture
• BOutdoor air and as a normal background indoor presence
• CThe human bloodstream
• DFrozen food storage

Mycotoxins are BEST defined as:

• AThe proteins on spore walls that cause allergic reactions
• BToxic secondary metabolites produced by certain molds under stress
• CAntibiotics produced by Penicillium
• DAny compound that gives mold its color

Which mycotoxin family is MOST strongly associated with Stachybotrys chartarum?

• AAflatoxins
• BOchratoxins
• CTrichothecenes (e.g., satratoxins)
• DErgot alkaloids

Which Aspergillus species is a primary aflatoxin producer in food and agricultural commodities?

• AAspergillus fumigatus
• BAspergillus flavus
• CAspergillus versicolor
• DAspergillus niger

Which of the following is a 'water-damage indicator' species frequently flagged on lab reports as suggestive of chronic indoor moisture?

• ACladosporium herbarum
• BAlternaria alternata
• CChaetomium globosum
• DEpicoccum nigrum

Alternaria spores on a spore-trap report are MOST commonly associated with:

• ABuilding water damage only
• BOutdoor air, agricultural environments, and seasonal allergy
• CSewer gas
• DAsbestos disturbance

What characteristic distinguishes Stachybotrys spores under direct microscopy from Aspergillus/Penicillium spores?

• AStachybotrys spores are smaller and round
• BStachybotrys spores are larger (7-12 µm), dark, ellipsoidal, and often striated or warty
• CStachybotrys spores are colorless
• DStachybotrys spores are spherical and smooth

Why is Stachybotrys often UNDERREPORTED on indoor air samples even when it is present on surfaces?

• AStachybotrys spores degrade in air
• BSpores are large, heavy, and produced in slimy droplets that do not aerosolize easily wit…
• CStachybotrys grows only at night
• DLabs cannot identify Stachybotrys

Which of the following is TRUE about indoor mold spores compared with bacteria?

• AMold spores are smaller than bacteria
• BMold spores are typically much larger (2-50+ µm) than bacteria (0.5-2 µm)
• CMold and bacteria are the same organism
• DMold spores cannot be airborne

What is the term for the airborne fragments of mold hyphae and spore parts that are smaller than intact spores?

• AConidiophores
• BFungal fragments (fungal sub-particles)
• CSclerotia
• DRhizomorphs

Which of the following is the MOST important environmental factor controlling mold growth on building materials?

• ATemperature
• BLiquid water or sustained high surface humidity
• CLight
• DAtmospheric pressure

Which mold genus is a common 'xerophilic' (low-water-activity) early colonist on surfaces with elevated humidity but no liquid water?

• AStachybotrys chartarum
• BAspergillus restrictus / Wallemia / Eurotium
• CChaetomium globosum
• DFusarium

Approximately how long after water intrusion can visible mold growth typically begin under favorable conditions?

• AWithin 1 hour
• BWithin 24-48 hours on porous, organic materials
• COnly after 2 weeks
• DOnly after 6 months

Which type of immune response is responsible for mold-related ALLERGIC rhinitis and allergic asthma?

• AIgE-mediated (Type I) hypersensitivity
• BCell-mediated tuberculosis-like response
• CToxin-mediated direct cellular damage
• DAnaphylactic shock only

Hypersensitivity pneumonitis (HP) is BEST described as:

• AA mild seasonal allergy
• BA delayed immune-mediated lung inflammation triggered by repeated inhalation of organic a…
• CAn infectious bacterial pneumonia
• DA skin reaction only

Which of the following is a recognized SENSITIVE population for mold exposure?

• AHealthy young adults
• BInfants, the elderly, asthmatics, allergic individuals, and immunocompromised patients
• CConstruction workers without medical conditions
• DOffice workers in a dry climate

Which of the following is the MOST common symptom complex reported by occupants of moldy buildings?

• AHearing loss
• BUpper-respiratory symptoms (nasal congestion, sneezing), eye irritation, cough, and heada…
• CSkin pigmentation changes
• DBone pain

For asthmatic occupants, indoor mold exposure is associated with:

• ANo effect on asthma
• BIncreased asthma symptoms, exacerbations, and reduced lung function
• CCure of asthma
• DOnly summer-time allergy

Which agency's 2004 report 'Damp Indoor Spaces and Health' is a foundational scientific reference on mold health effects?

• AEPA
• BInstitute of Medicine (IOM), now National Academy of Medicine
• CCDC
• DNIOSH

Mycotoxin causation of disease through inhalation exposure in typical indoor environments is BEST characterized as:

• ADefinitively established for all indoor mold scenarios
• BPlausible but not fully established by current peer-reviewed evidence
• CImpossible
• DThe same as ingested mycotoxin causation

Which scenario describes invasive aspergillosis risk?

• AA healthy adult inhaling normal outdoor Aspergillus levels
• BA neutropenic bone-marrow transplant patient with high-level indoor Aspergillus fumigatus…
• CChildren playing outdoors
• DAn adult swimming in a chlorinated pool

Which respiratory symptom is MOST associated with Stachybotrys exposure in published case reports?

• AHearing loss
• BPulmonary hemorrhage in infants (controversial, single Cleveland cluster)
• CSkin cancer
• DChronic kidney disease

What is the InterNACHI mold inspector's APPROPRIATE response when occupants describe specific medical symptoms attributed to mold?

• ADiagnose the illness on-site
• BDocument the symptom history as occupant statements, and recommend the occupants consult…
• CTell occupants the mold is harmless
• DProvide medication recommendations

Which of the following is NOT a category of building water damage per the IICRC S500 standard often referenced by mold inspectors?

• ACategory 1 — Clean water (e.g., supply line)
• BCategory 2 — Gray water (e.g., dishwasher discharge, toilet overflow without solids)
• CCategory 3 — Black water (e.g., sewage, flood water)
• DCategory 4 — Saltwater only

A failed roof flashing around a chimney is MOST likely to cause mold growth in which location FIRST?

• ABasement floor
• BAttic sheathing and rafters adjacent to the chimney
• CGarage slab
• DExterior siding

Which of the following is a COMMON HVAC-related moisture source for indoor mold?

• AThe thermostat
• BThe condensate drain pan and evaporator coil, especially when biofilm forms or the drain…
• CThe compressor unit
• DThe return-air filter media

Which area of a basement is MOST susceptible to foundation moisture intrusion?

• AThe center of the floor only
• BThe cove (wall-to-floor joint), wall cracks, and around penetrations
• COnly the ceiling
• DThe light fixtures

What is 'capillary moisture' through a concrete slab?

• AWater vapor diffusing through the slab
• BLiquid water drawn upward through the small pores of concrete by capillary action from th…
• CWater leaking through cracks
• DWater from a plumbing leak

What relative humidity (RH) range does EPA recommend for indoor environments to control mold growth?

• A10-20%
• B30-50% (with 60% as the upper limit)
• C65-75%
• DAbove 80%

What is the 'dew point' in the context of building moisture?

• AThe temperature at which water boils
• BThe temperature at which air becomes saturated and water vapor condenses on cooler surfac…
• CThe lowest outdoor temperature of the day
• DThe freezing temperature

A long-standing slow leak under a kitchen sink is MOST likely to cause:

• ANo mold problem because the area is enclosed
• BMold growth in the sink-base cabinet, on subfloor and surrounding wall framing
• CMold growth only on the countertop
• DFoundation cracking

Bathroom mold growth on ceilings and walls in the absence of a leak is MOST often caused by:

• AA failing roof
• BInadequate exhaust ventilation allowing humid shower air to condense on cool surfaces
• CCold supply water
• DCarpet outgassing

Which exterior grading condition is MOST likely to cause basement moisture problems?

• ASoil sloping AWAY from the foundation
• BSoil sloping TOWARD the foundation, allowing surface water to pond at the wall
• CMulched landscaping
• DConcrete patios drained away from the home

A disconnected or short downspout extension that discharges water 1 foot from the foundation is BEST corrected by:

• ARemoving the downspout
• BExtending the discharge at least 4-6 feet away from the foundation, onto a slope or to an…
• CPointing the downspout straight up
• DNo action is needed

Which finished basement feature creates the HIGHEST mold risk?

• APainted concrete walls
• BBelow-grade carpet over a slab, with no vapor barrier and no dehumidification
• CVinyl plank flooring with sealed seams
• DSealed concrete floors

Why is crawlspace moisture a common driver of mold in the rooms above it?

• ACrawlspaces are colder than basements
• BThe 'stack effect' draws crawlspace air upward through the floor into living spaces, carr…
• CCrawlspaces have no spores
• DCrawlspace mold cannot become airborne

Window condensation in winter is MOST likely caused by:

• AHigh outdoor temperatures
• BIndoor humidity higher than the dew point of the cold window surface
• CClosed curtains
• DArgon-filled triple-pane windows

What is the FIRST step under the IAC2 Mold Inspection Standards of Practice when entering a building for a mold inspection?

• AOpen all spore-trap cassettes
• BConduct a non-invasive visual inspection of readily accessible, visible, and installed sy…
• CDrill exploratory holes in walls
• DBegin remediation

Which tool is MOST useful for non-invasively detecting hidden moisture behind walls and ceilings?

• AA flashlight only
• BAn infrared thermal imaging camera, combined with a confirmatory moisture meter
• CA magnifying glass
• DA multimeter

What is the difference between a 'pin' moisture meter and a 'pinless' moisture meter?

• AThere is no difference
• BPin meters use electrodes that penetrate the material and measure electrical resistance;…
• CPinless meters are inaccurate
• DPin meters can only measure metal

What does a hygrometer measure?

• AAir pressure
• BTemperature and relative humidity (and often dew point)
• CCarbon dioxide
• DMold spore count

What is the BEST practice for documenting visual findings during a mold inspection?

• AMemorize findings and write the report from memory
• BTake date-stamped photographs of every suspect area, water stain, and meter/IR reading, a…
• CTake a single photo of the building exterior
• DSketch findings without photos

Under the IAC2 SoP, the mold inspection includes inspection of which of the following areas?

• AOnly the basement
• BRoof (from the ground level), exterior, foundation, basement, HVAC, plumbing, attic, and…
• COnly the bathroom
• DOnly the kitchen

Which of the following is NOT something the mold inspector is required to do under the IAC2 SoP?

• ADocument conditions conducive to mold growth
• BWalk on roof surfaces
• CNote water staining and musty odors
• DMeasure moisture, temperature, and humidity