IICRC WRT FINAL EXAM 2026/2027
PREP QUESTIONS AND ANSWERS
1. What is the primary objective of a restorer when managing a Category 3 water intrusion?
A. To perform rapid structural drying using high-velocity air movers immediately.
B. To utilize LGR dehumidifiers to reduce vapor pressure to below 40 GPP.
C. To protect public health by containing and removing contaminants before drying.
D. To apply antimicrobial biocides as a substitute for physical cleaning.
Answer: C
Conceptual Explanation: In Category 3 (Grossly Contaminated) water losses, the safety of
occupants and workers is the priority. Contaminants must be removed or neutralized
before significant air movement occurs to prevent aerosolization.
2. Which psychrometric value represents the actual weight of water vapor in the air,
expressed in grains per pound (gpp)?
A. Relative Humidity
B. Humidity Ratio
C. Dew Point
D. Vapor Pressure
,Answer: B
Conceptual Explanation: Humidity Ratio (specifically Specific Humidity) measures the
weight of water vapor per unit weight of dry air, typically expressed in grains per pound
(gpp).
3. A water intrusion affecting only a small area of a room (e.g., less than 5% of combined
floor, wall, and ceiling surface area) is classified as:
A. Class 4
B. Class 2
C. Class 3
D. Class 1
Answer: D
Conceptual Explanation: Class 1 water intrusions involve the least amount of water and
affect a small area of low-porosity materials, where the evaporation load is minimal.
4. What is the ‘Fiber Saturation Point’ for most wood species used in construction?
A. 10-15%
B. 20-25%
C. Over 40%
D. 28-30%
Answer: D
, Conceptual Explanation: The Fiber Saturation Point (FSP) is the point (typically around
30%) where the cell walls are completely saturated but no free water exists in the cell
cavities.
5. Which type of dehumidifier is most effective when the ambient temperature is below 70°F
and the specific humidity is below 30 GPP?
A. Desiccant
B. Low Grain Refrigerant (LGR)
C. Conventional Refrigerant
D. Thermo-electric
Answer: A
Conceptual Explanation: Desiccants use chemicals (like silica gel) to absorb moisture and
are not limited by temperature-driven condensation, making them superior for low GPP
and low temperature environments.
6. When should a restorer consult with an Independent Environmental Professional (IEP)?
A. When there is a possibility of hazardous materials like asbestos or lead.
B. On every Class 1 water loss.
C. Only after the drying process is complete.
D. When the customer requests a discount.
Answer: A
PREP QUESTIONS AND ANSWERS
1. What is the primary objective of a restorer when managing a Category 3 water intrusion?
A. To perform rapid structural drying using high-velocity air movers immediately.
B. To utilize LGR dehumidifiers to reduce vapor pressure to below 40 GPP.
C. To protect public health by containing and removing contaminants before drying.
D. To apply antimicrobial biocides as a substitute for physical cleaning.
Answer: C
Conceptual Explanation: In Category 3 (Grossly Contaminated) water losses, the safety of
occupants and workers is the priority. Contaminants must be removed or neutralized
before significant air movement occurs to prevent aerosolization.
2. Which psychrometric value represents the actual weight of water vapor in the air,
expressed in grains per pound (gpp)?
A. Relative Humidity
B. Humidity Ratio
C. Dew Point
D. Vapor Pressure
,Answer: B
Conceptual Explanation: Humidity Ratio (specifically Specific Humidity) measures the
weight of water vapor per unit weight of dry air, typically expressed in grains per pound
(gpp).
3. A water intrusion affecting only a small area of a room (e.g., less than 5% of combined
floor, wall, and ceiling surface area) is classified as:
A. Class 4
B. Class 2
C. Class 3
D. Class 1
Answer: D
Conceptual Explanation: Class 1 water intrusions involve the least amount of water and
affect a small area of low-porosity materials, where the evaporation load is minimal.
4. What is the ‘Fiber Saturation Point’ for most wood species used in construction?
A. 10-15%
B. 20-25%
C. Over 40%
D. 28-30%
Answer: D
, Conceptual Explanation: The Fiber Saturation Point (FSP) is the point (typically around
30%) where the cell walls are completely saturated but no free water exists in the cell
cavities.
5. Which type of dehumidifier is most effective when the ambient temperature is below 70°F
and the specific humidity is below 30 GPP?
A. Desiccant
B. Low Grain Refrigerant (LGR)
C. Conventional Refrigerant
D. Thermo-electric
Answer: A
Conceptual Explanation: Desiccants use chemicals (like silica gel) to absorb moisture and
are not limited by temperature-driven condensation, making them superior for low GPP
and low temperature environments.
6. When should a restorer consult with an Independent Environmental Professional (IEP)?
A. When there is a possibility of hazardous materials like asbestos or lead.
B. On every Class 1 water loss.
C. Only after the drying process is complete.
D. When the customer requests a discount.
Answer: A
