IICRC WRT CERTIFICATION PRACTICE
EXAM QUESTIONS AND ANSWERS
1. Which category of water originates from a source that does not pose substantial risk from
dermal, ingestion, or inhalation exposure?
A. Category 2
B. Category 3
C. Category 1
D. Special Category
Answer: C
Conceptual Explanation: Category 1 water originates from a sanitary water source and
does not pose substantial risk from exposure.
2. According to the IICRC S500, how many categories of water are there?
A. 3
B. 5
C. 2
,D. 4
Answer: A
Conceptual Explanation: The S500 defines three categories of water: Category 1, 2, and 3.
3. Which class of water loss involves the greatest volume of water and the greatest amount of
absorption into materials like subflooring and insulation?
A. Class 3
B. Class 1
C. Class 4
D. Class 2
Answer: A
Conceptual Explanation: Class 3 water intrusion involves the entire area being affected,
including ceilings, walls, and subfloor, representing the greatest volume of water.
4. What is the ‘Fiber Saturation Point’ for most wood species?
A. 30% MC
B. 20% MC
C. 15% MC
D. 45% MC
Answer: A
, Conceptual Explanation: The Fiber Saturation Point (FSP) is approximately 30% moisture
content, where the cell walls are saturated but the cell cavities are empty.
5. Which psychrometric term refers to the weight of water vapor in a given weight of dry air?
A. Relative Humidity
B. Humidity Ratio (Grains per Pound)
C. Dew Point
D. Vapor Pressure
Answer: B
Conceptual Explanation: Humidity Ratio, expressed as Grains Per Pound (GPP), measures
the weight of water vapor in dry air.
6. What occurs when the air temperature reaches the dew point?
A. Evaporation increases
B. Vapor pressure drops to zero
C. Relative humidity becomes 100%
D. Air becomes unsaturated
Answer: C
Conceptual Explanation: At the dew point, air is 100% saturated and can no longer hold
additional moisture, leading to condensation.
EXAM QUESTIONS AND ANSWERS
1. Which category of water originates from a source that does not pose substantial risk from
dermal, ingestion, or inhalation exposure?
A. Category 2
B. Category 3
C. Category 1
D. Special Category
Answer: C
Conceptual Explanation: Category 1 water originates from a sanitary water source and
does not pose substantial risk from exposure.
2. According to the IICRC S500, how many categories of water are there?
A. 3
B. 5
C. 2
,D. 4
Answer: A
Conceptual Explanation: The S500 defines three categories of water: Category 1, 2, and 3.
3. Which class of water loss involves the greatest volume of water and the greatest amount of
absorption into materials like subflooring and insulation?
A. Class 3
B. Class 1
C. Class 4
D. Class 2
Answer: A
Conceptual Explanation: Class 3 water intrusion involves the entire area being affected,
including ceilings, walls, and subfloor, representing the greatest volume of water.
4. What is the ‘Fiber Saturation Point’ for most wood species?
A. 30% MC
B. 20% MC
C. 15% MC
D. 45% MC
Answer: A
, Conceptual Explanation: The Fiber Saturation Point (FSP) is approximately 30% moisture
content, where the cell walls are saturated but the cell cavities are empty.
5. Which psychrometric term refers to the weight of water vapor in a given weight of dry air?
A. Relative Humidity
B. Humidity Ratio (Grains per Pound)
C. Dew Point
D. Vapor Pressure
Answer: B
Conceptual Explanation: Humidity Ratio, expressed as Grains Per Pound (GPP), measures
the weight of water vapor in dry air.
6. What occurs when the air temperature reaches the dew point?
A. Evaporation increases
B. Vapor pressure drops to zero
C. Relative humidity becomes 100%
D. Air becomes unsaturated
Answer: C
Conceptual Explanation: At the dew point, air is 100% saturated and can no longer hold
additional moisture, leading to condensation.
