CPR Water, Fire & Mold Restoration Techniques 3 — Questions and Answers
Question 1: What is the target indoor relative humidity range recommended by IICRC S500 to inhibit mold growth during water damage restoration?
- 20–30%
- 30–50% (Correct answer)
- 55–65%
- 65–75%
Correct answer: 30–50%
IICRC S500 recommends maintaining indoor relative humidity between 30–50% during restoration to inhibit mold growth and support structural drying.
Question 2: Which type of smoke residue is most difficult to clean and typically requires chemical sponges and specialized solvents?
- Wet smoke residue from slow-burning, low-heat fires (Correct answer)
- Dry smoke residue from fast-burning, high-temperature fires
- Protein smoke residue from cooking fires
- Fuel oil soot from furnace puff-backs
Correct answer: Wet smoke residue from slow-burning, low-heat fires
Wet smoke residue from slow, smoldering fires is sticky, smeary, and has a strong odor, making it the most difficult to clean and requiring specialized products.
Question 3: During a large-loss water restoration project, a psychrometric calculation shows the Specific Humidity (SH) inside is higher than outside. What is the correct action?
- Increase dehumidifier capacity only
- Use mechanical ventilation to introduce outside air and reduce indoor SH
- Seal the structure tightly and run dehumidifiers (Correct answer)
- Open all windows to accelerate evaporation
Correct answer: Seal the structure tightly and run dehumidifiers
When indoor SH exceeds outdoor SH, introducing outside air would add moisture to the structure, so the building should be sealed and dehumidification should be relied upon.
Question 4: What is the primary health concern associated with Stachybotrys chartarum (black mold)?
- It produces mycotoxins that can cause serious respiratory and neurological effects (Correct answer)
- It causes only mild skin irritation upon contact
- It is purely aesthetic and presents no health risk
- It primarily affects pets rather than humans
Correct answer: It produces mycotoxins that can cause serious respiratory and neurological effects
Stachybotrys chartarum can produce trichothecene mycotoxins associated with serious respiratory illness, immune suppression, and neurological symptoms in exposed individuals.
Question 5: A technician is restoring fire-damaged kitchen cabinets. Protein smoke residue is present. Which cleaning method is MOST appropriate?
- Dry sponge wiping in one direction
- HEPA vacuum followed by enzymatic cleaner (Correct answer)
- Abrasive scrubbing with steel wool
- Pressure washing with cold water
Correct answer: HEPA vacuum followed by enzymatic cleaner
Protein residue requires enzymatic or alkaline cleaners to break down the protein compounds; vacuuming first removes loose deposits before wet cleaning.
Question 6: When establishing containment during mold remediation, what is the purpose of maintaining negative air pressure inside the containment zone?
- To speed up the drying process
- To prevent mold spores from migrating to unaffected areas (Correct answer)
- To increase the effectiveness of biocide applications
- To reduce the required PPE level for workers
Correct answer: To prevent mold spores from migrating to unaffected areas
Negative air pressure ensures that any air movement goes INTO the containment zone rather than out, preventing cross-contamination of unaffected building areas.
Question 7: Which document should a restoration contractor obtain BEFORE beginning demolition work in a pre-1980 structure with fire damage?
- Building permit only
- Asbestos and lead-paint survey or testing report (Correct answer)
- Insurance adjuster's written approval
- Certificate of occupancy from the local fire marshal
Correct answer: Asbestos and lead-paint survey or testing report
Structures built before 1980 may contain asbestos and lead paint; a survey or testing report is legally required before demolition to ensure safe handling and disposal.
CPR Water, Fire & Mold Restoration Techniques 3
What is the target indoor relative humidity range recommended by IICRC S500 to inhibit mold growth during water damage restoration?