CMA Mold Remediation & Safety Standards 3 — Questions and Answers
Question 1: Under the IICRC S520 standard, what condition code is assigned to a surface where mold growth is confirmed visually and/or analytically on materials that can be cleaned and restored?
- Condition 1 — Normal fungal ecology
- Condition 2 — Settled spores or fungal fragments
- Condition 3 — Actual mold growth or concentrated spore presence (Correct answer)
- Condition 4 — Structural compromise from fungal damage
Correct answer: Condition 3 — Actual mold growth or concentrated spore presence
Condition 3 indicates actual mold growth or highly elevated spore concentrations on surfaces and requires full remediation protocols.
Question 2: Which personal protective equipment (PPE) component is specifically required to prevent dermal exposure to mold during remediation activities involving heavy contamination?
- Safety glasses with side shields
- Disposable Tyvek or equivalent full-body coveralls (Correct answer)
- Hard hat with mold-resistant coating
- Leather work gloves with cotton liner
Correct answer: Disposable Tyvek or equivalent full-body coveralls
Disposable full-body coveralls prevent mold spores from contaminating skin and clothing, which could spread contamination beyond the work area.
Question 3: A negative air machine (NAM) used in mold remediation must exhaust air to the building exterior. What is the minimum HEPA filtration efficiency required for the exhaust air?
- 85% efficiency at 0.3 microns
- 95% efficiency at 0.3 microns (MERV-16)
- 99.97% efficiency at 0.3 microns (true HEPA) (Correct answer)
- 99.99% efficiency at 0.12 microns (ULPA)
Correct answer: 99.97% efficiency at 0.3 microns (true HEPA)
True HEPA filters with 99.97% efficiency at 0.3 microns are required on negative air machines to prevent exhausting mold spores into exterior areas or re-entry points.
Question 4: A mold assessor is hired to perform a post-remediation verification inspection. Which of the following sampling strategies is MOST appropriate for clearance testing?
- Bulk samples of remaining wall material only
- Air samples inside the remediated area compared to outdoor control samples (Correct answer)
- Tape lift samples from adjacent unaffected rooms
- Wipe samples from HVAC diffusers throughout the building
Correct answer: Air samples inside the remediated area compared to outdoor control samples
Clearance air sampling comparing the remediated area to outdoor controls is the standard PRV method, as it directly measures airborne spore levels that indicate remediation success.
Question 5: When must a mold remediation worker undergo medical evaluation for respirator use according to OSHA's Respiratory Protection Standard (29 CFR 1910.134)?
- Only if the worker has previously reported breathing difficulties
- Before being assigned to wear a respirator for any mold remediation work (Correct answer)
- Only when using a supplied-air respirator, not air-purifying types
- After 30 days of continuous respirator use on remediation projects
Correct answer: Before being assigned to wear a respirator for any mold remediation work
OSHA 29 CFR 1910.134 requires medical evaluation before any worker is assigned to wear a respirator to ensure they are physically capable of wearing it safely.
Question 6: Which moisture reading threshold in wood framing generally indicates an elevated risk for mold growth and requires remediation or drying before enclosure?
- Above 15% moisture content
- Above 19% moisture content (Correct answer)
- Above 25% moisture content
- Above 30% moisture content
Correct answer: Above 19% moisture content
Wood moisture content above 19% is widely recognized as the threshold above which mold growth risk significantly increases and drying is required before enclosure.
Question 7: In a multi-family residential building, mold was discovered in one unit's bathroom. What scope of investigation is required before limiting remediation to that single unit?
- No investigation needed — remediate only the visible area and close the work order
- Inspect adjacent units, the unit above, and the unit below for moisture intrusion and associated mold (Correct answer)
- Conduct air sampling of all 200 units in the building before proceeding
- Apply biocide throughout all connected HVAC ductwork as a precautionary measure
Correct answer: Inspect adjacent units, the unit above, and the unit below for moisture intrusion and associated mold
Mold in one unit often indicates moisture migration through shared walls, floors, or plumbing chases, requiring inspection of adjacent units to determine full scope.
CMA Mold Remediation & Safety Standards 3
Under the IICRC S520 standard, what condition code is assigned to a surface where mold growth is confirmed visually and/or analytically on materials that can be cleaned and restored?