Minnesota Mold Remediation
Contractor Exam Practice Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
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1. What is the primary cause of mold growth in buildings?
A. Low temperature
B. Excess moisture
C. Poor lighting
D. High elevation
Answer: B. Excess moisture
Rationale: Mold requires moisture to grow, making water intrusion
or humidity the primary driver of indoor mold problems.
2. Which material is most susceptible to mold growth?
A. Glass
B. Concrete
C. Drywall
, D. Steel
Answer: C. Drywall
Rationale: Drywall is porous and retains moisture, making it highly
vulnerable to mold colonization.
3. What is the first step in mold remediation?
A. Painting affected surfaces
B. Identifying moisture source
C. Applying biocide
D. Removing HVAC system
Answer: B. Identifying moisture source
Rationale: Stopping moisture intrusion is essential before any
remediation can be effective.
4. What type of respirator is commonly required during mold
remediation?
A. Surgical mask
B. N95 respirator
C. Cloth mask
D. Paper dust mask
Answer: B. N95 respirator
Rationale: N95 respirators filter airborne spores and are commonly
used for mold work.
,5. What is the purpose of containment during mold remediation?
A. Increase airflow
B. Prevent spread of spores
C. Dry materials faster
D. Reduce humidity
Answer: B. Prevent spread of spores
Rationale: Containment isolates contaminated areas to avoid cross-
contamination.
6. What tool is used to create negative air pressure?
A. Dehumidifier
B. HEPA air scrubber
C. Fan heater
D. Air conditioner
Answer: B. HEPA air scrubber
Rationale: HEPA air scrubbers exhaust filtered air, maintaining
negative pressure in containment zones.
7. Which organism is most commonly referred to as “toxic black mold”?
A. Aspergillus
B. Penicillium
C. Stachybotrys chartarum
D. Cladosporium
Answer: C. Stachybotrys chartarum
, Rationale: This species is often associated with high moisture
environments and is commonly labeled “toxic black mold.”
8. What humidity level promotes mold growth?
A. Below 20%
B. 30–40%
C. Above 60%
D. Below 10%
Answer: C. Above 60%
Rationale: High relative humidity supports mold growth indoors.
9. What is HEPA filtration designed to capture?
A. Large debris only
B. Gases
C. Particles as small as 0.3 microns
D. Water vapor
Answer: C. Particles as small as 0.3 microns
Rationale: HEPA filters capture fine airborne particles including mold
spores.
10. What is the purpose of a dehumidifier in remediation?
A. Increase airflow
B. Reduce moisture levels
C. Kill mold directly
D. Seal contaminated areas
Contractor Exam Practice Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
1. What is the primary cause of mold growth in buildings?
A. Low temperature
B. Excess moisture
C. Poor lighting
D. High elevation
Answer: B. Excess moisture
Rationale: Mold requires moisture to grow, making water intrusion
or humidity the primary driver of indoor mold problems.
2. Which material is most susceptible to mold growth?
A. Glass
B. Concrete
C. Drywall
, D. Steel
Answer: C. Drywall
Rationale: Drywall is porous and retains moisture, making it highly
vulnerable to mold colonization.
3. What is the first step in mold remediation?
A. Painting affected surfaces
B. Identifying moisture source
C. Applying biocide
D. Removing HVAC system
Answer: B. Identifying moisture source
Rationale: Stopping moisture intrusion is essential before any
remediation can be effective.
4. What type of respirator is commonly required during mold
remediation?
A. Surgical mask
B. N95 respirator
C. Cloth mask
D. Paper dust mask
Answer: B. N95 respirator
Rationale: N95 respirators filter airborne spores and are commonly
used for mold work.
,5. What is the purpose of containment during mold remediation?
A. Increase airflow
B. Prevent spread of spores
C. Dry materials faster
D. Reduce humidity
Answer: B. Prevent spread of spores
Rationale: Containment isolates contaminated areas to avoid cross-
contamination.
6. What tool is used to create negative air pressure?
A. Dehumidifier
B. HEPA air scrubber
C. Fan heater
D. Air conditioner
Answer: B. HEPA air scrubber
Rationale: HEPA air scrubbers exhaust filtered air, maintaining
negative pressure in containment zones.
7. Which organism is most commonly referred to as “toxic black mold”?
A. Aspergillus
B. Penicillium
C. Stachybotrys chartarum
D. Cladosporium
Answer: C. Stachybotrys chartarum
, Rationale: This species is often associated with high moisture
environments and is commonly labeled “toxic black mold.”
8. What humidity level promotes mold growth?
A. Below 20%
B. 30–40%
C. Above 60%
D. Below 10%
Answer: C. Above 60%
Rationale: High relative humidity supports mold growth indoors.
9. What is HEPA filtration designed to capture?
A. Large debris only
B. Gases
C. Particles as small as 0.3 microns
D. Water vapor
Answer: C. Particles as small as 0.3 microns
Rationale: HEPA filters capture fine airborne particles including mold
spores.
10. What is the purpose of a dehumidifier in remediation?
A. Increase airflow
B. Reduce moisture levels
C. Kill mold directly
D. Seal contaminated areas
