IICRC WATER RESTORATION
TECHNICIAN (WRT) ADVANCED
PRACTICE EXAM
1. Which of the following describes the ‘Dew Point’ in a structural drying environment?
A. The temperature at which air becomes saturated and condensation begins to form.
B. The amount of moisture in the air expressed as a percentage of the total capacity.
C. The pressure exerted by water vapor on a surface.
D. The weight of water vapor in a specific volume of air.
Answer: A
Conceptual Explanation: Dew point is the temperature at which the air is 100% saturated
(100% RH). If surfaces are at or below this temperature, condensation will occur.
2. A Category 2 water intrusion is characterized by which of the following?
A. Water containing significant contamination and potential to cause discomfort or
sickness.
B. Water from a clean source like a broken supply line.
C. Water that is grossly unsanitary and contains pathogenic agents.
D. Water that has been standing for more than 72 hours regardless of source.
,Answer: A
Conceptual Explanation: Category 2 water (formerly ‘grey water’) contains significant
contamination, such as discharge from dishwashers or washing machines.
3. What is the primary purpose of an LGR (Low Grain Refrigerant) dehumidifier compared to a
conventional refrigerant dehumidifier?
A. To use less electricity while moving more air volume.
B. To filter out mold spores more effectively than standard units.
C. To increase the temperature of the room to speed up evaporation.
D. To continue removing moisture at much lower GPP (Grains Per Pound) levels.
Answer: D
Conceptual Explanation: LGR dehumidifiers are designed to remove water vapor
effectively below 40 GPP, whereas conventional units lose efficiency as the air gets drier.
4. In the S500 standard, what is ‘Class 4’ water intrusion defined as?
A. Large surface area of water with minimal absorption into materials.
B. Water that affects only part of a room with low evaporation materials.
C. Deeply held or bound water in low-porosity materials like hardwood or concrete.
D. A situation involving sewage or floodwaters from a river.
Answer: C
, Conceptual Explanation: Class 4 involves ‘specialty drying’ situations where moisture is
trapped in materials like stone, brick, concrete, or hardwood floors.
5. Which psychrometric value is most useful for determining the direction of moisture
movement?
A. Vapor Pressure
B. Dry Bulb Temperature
C. Relative Humidity (RH)
D. Airflow Velocity
Answer: A
Conceptual Explanation: Moisture moves from areas of high vapor pressure to areas of
low vapor pressure. This pressure differential drives the drying process.
6. What is the minimum number of air changes per hour (ACH) typically required for effective
structural drying?
A. 1-2 ACH
B. Based on the calculation of one air mover per 50-70 square feet of affected floor.
C. 4-6 ACH
D. Exactly 10 ACH regardless of class.
Answer: B
TECHNICIAN (WRT) ADVANCED
PRACTICE EXAM
1. Which of the following describes the ‘Dew Point’ in a structural drying environment?
A. The temperature at which air becomes saturated and condensation begins to form.
B. The amount of moisture in the air expressed as a percentage of the total capacity.
C. The pressure exerted by water vapor on a surface.
D. The weight of water vapor in a specific volume of air.
Answer: A
Conceptual Explanation: Dew point is the temperature at which the air is 100% saturated
(100% RH). If surfaces are at or below this temperature, condensation will occur.
2. A Category 2 water intrusion is characterized by which of the following?
A. Water containing significant contamination and potential to cause discomfort or
sickness.
B. Water from a clean source like a broken supply line.
C. Water that is grossly unsanitary and contains pathogenic agents.
D. Water that has been standing for more than 72 hours regardless of source.
,Answer: A
Conceptual Explanation: Category 2 water (formerly ‘grey water’) contains significant
contamination, such as discharge from dishwashers or washing machines.
3. What is the primary purpose of an LGR (Low Grain Refrigerant) dehumidifier compared to a
conventional refrigerant dehumidifier?
A. To use less electricity while moving more air volume.
B. To filter out mold spores more effectively than standard units.
C. To increase the temperature of the room to speed up evaporation.
D. To continue removing moisture at much lower GPP (Grains Per Pound) levels.
Answer: D
Conceptual Explanation: LGR dehumidifiers are designed to remove water vapor
effectively below 40 GPP, whereas conventional units lose efficiency as the air gets drier.
4. In the S500 standard, what is ‘Class 4’ water intrusion defined as?
A. Large surface area of water with minimal absorption into materials.
B. Water that affects only part of a room with low evaporation materials.
C. Deeply held or bound water in low-porosity materials like hardwood or concrete.
D. A situation involving sewage or floodwaters from a river.
Answer: C
, Conceptual Explanation: Class 4 involves ‘specialty drying’ situations where moisture is
trapped in materials like stone, brick, concrete, or hardwood floors.
5. Which psychrometric value is most useful for determining the direction of moisture
movement?
A. Vapor Pressure
B. Dry Bulb Temperature
C. Relative Humidity (RH)
D. Airflow Velocity
Answer: A
Conceptual Explanation: Moisture moves from areas of high vapor pressure to areas of
low vapor pressure. This pressure differential drives the drying process.
6. What is the minimum number of air changes per hour (ACH) typically required for effective
structural drying?
A. 1-2 ACH
B. Based on the calculation of one air mover per 50-70 square feet of affected floor.
C. 4-6 ACH
D. Exactly 10 ACH regardless of class.
Answer: B