IICRC WATER RESTORATION TECHNICIAN
IICRC WATER RESTORATION TECHNICIAN (WRT) READINESS
EXAM | QUESTIONS AND ANSWERS | VERIFIED ANSWERS PLUS
RATIONALES | LATEST EXAM UPDATE
PRINCIPLES, PSYCHROMETRICS & SCIENCE
1. What primarily drives evaporation from a wet material surface?
A. Air velocity alone
B. Temperature alone
C. Vapor pressure differential
D. Relative humidity alone
ANS >> C. Vapor pressure differential
Rationale: Evaporation is driven by differences in vapor pressure between
material and air.
2. Which psychrometric change most increases grain depression?
A. Increasing RH
B. Decreasing dry bulb temperature
C. Lowering dew point
D. Increasing moisture content of air
ANS >> C. Lowering dew point
Rationale: Lower dew point increases the air’s moisture-holding capacity.
3. What does equilibrium moisture content (EMC) represent?
A. Maximum moisture a material can hold
B. Moisture at saturation
C. Moisture level matching ambient conditions
D. Zero moisture state
ANS >> C. Moisture level matching ambient conditions
Rationale: EMC occurs when material and air reach balance.
,IICRC WATER RESTORATION TECHNICIAN
4. Which condition reduces evaporation even with high airflow?
A. Low RH
B. High grain depression
C. Saturated ambient air
D. Elevated temperature
ANS >> C. Saturated ambient air
Rationale: Moist air cannot accept additional vapor.
5. What happens when materials are dried below normal EMC?
A. Faster restoration
B. Structural strengthening
C. Shrinkage and cracking
D. Increased microbial risk
ANS >> C. Shrinkage and cracking
Rationale: Over-drying damages materials.
6. Which parameter best confirms drying progress?
A. Elapsed time
B. Equipment count
C. Comparative moisture readings
D. Ambient temperature
ANS >> C. Comparative moisture readings
Rationale: Objective measurements confirm progress.
7. Which factor MOST affects diffusion drying?
A. Gravity
B. Vapor pressure
C. Capillary action
D. Air turbulence
ANS >> B. Vapor pressure
Rationale: Diffusion depends on vapor pressure gradients.
,IICRC WATER RESTORATION TECHNICIAN
8. Which statement about temperature is MOST accurate?
A. Higher temperature always improves drying
B. Heat alone dries materials
C. Heat increases vapor pressure
D. Heat reduces RH permanently
ANS >> C. Heat increases vapor pressure
Rationale: Higher temperature increases evaporation potential.
9. What is the psychrometric definition of grains?
A. Weight of liquid water
B. Relative humidity scale
C. Mass of water vapor per pound of dry air
D. Condensation rate
ANS >> C. Mass of water vapor per pound of dry air
Rationale: Grains quantify absolute moisture.
10. Why is RH alone unreliable for drying decisions?
A. It fluctuates constantly
B. It ignores temperature
C. It ignores airflow
D. It measures surface moisture
ANS >> B. It ignores temperature
Rationale: RH without temperature lacks context.
11. Which drying phase removes bound water?
A. Extraction
B. Constant rate
C. Falling rate
D. Migration
ANS >> C. Falling rate
Rationale: Bound water removal occurs during falling rate.
, IICRC WATER RESTORATION TECHNICIAN
12. What occurs if evaporation exceeds dehumidification?
A. Faster drying
B. Condensation risk
C. Lower RH
D. Stable grain depression
ANS >> B. Condensation risk
Rationale: Moisture accumulates in the air.
13. Which material has the highest EMC?
A. Concrete
B. Hardwood
C. Gypsum board
D. Carpet fiber
ANS >> A. Concrete
Rationale: Concrete stores large amounts of bound moisture.
14. What does “latent heat” refer to?
A. Sensible temperature change
B. Energy used to move air
C. Energy required to change water phase
D. Heat loss through walls
ANS >> C. Energy required to change water phase
Rationale: Evaporation requires latent heat.
15. Which reading indicates risk of secondary damage?
A. Stable RH
B. Moisture above dry standard
C. Ambient temperature of 22°C
D. Neutral pressure
ANS >> B. Moisture above dry standard
Rationale: Elevated moisture leads to damage.
IICRC WATER RESTORATION TECHNICIAN (WRT) READINESS
EXAM | QUESTIONS AND ANSWERS | VERIFIED ANSWERS PLUS
RATIONALES | LATEST EXAM UPDATE
PRINCIPLES, PSYCHROMETRICS & SCIENCE
1. What primarily drives evaporation from a wet material surface?
A. Air velocity alone
B. Temperature alone
C. Vapor pressure differential
D. Relative humidity alone
ANS >> C. Vapor pressure differential
Rationale: Evaporation is driven by differences in vapor pressure between
material and air.
2. Which psychrometric change most increases grain depression?
A. Increasing RH
B. Decreasing dry bulb temperature
C. Lowering dew point
D. Increasing moisture content of air
ANS >> C. Lowering dew point
Rationale: Lower dew point increases the air’s moisture-holding capacity.
3. What does equilibrium moisture content (EMC) represent?
A. Maximum moisture a material can hold
B. Moisture at saturation
C. Moisture level matching ambient conditions
D. Zero moisture state
ANS >> C. Moisture level matching ambient conditions
Rationale: EMC occurs when material and air reach balance.
,IICRC WATER RESTORATION TECHNICIAN
4. Which condition reduces evaporation even with high airflow?
A. Low RH
B. High grain depression
C. Saturated ambient air
D. Elevated temperature
ANS >> C. Saturated ambient air
Rationale: Moist air cannot accept additional vapor.
5. What happens when materials are dried below normal EMC?
A. Faster restoration
B. Structural strengthening
C. Shrinkage and cracking
D. Increased microbial risk
ANS >> C. Shrinkage and cracking
Rationale: Over-drying damages materials.
6. Which parameter best confirms drying progress?
A. Elapsed time
B. Equipment count
C. Comparative moisture readings
D. Ambient temperature
ANS >> C. Comparative moisture readings
Rationale: Objective measurements confirm progress.
7. Which factor MOST affects diffusion drying?
A. Gravity
B. Vapor pressure
C. Capillary action
D. Air turbulence
ANS >> B. Vapor pressure
Rationale: Diffusion depends on vapor pressure gradients.
,IICRC WATER RESTORATION TECHNICIAN
8. Which statement about temperature is MOST accurate?
A. Higher temperature always improves drying
B. Heat alone dries materials
C. Heat increases vapor pressure
D. Heat reduces RH permanently
ANS >> C. Heat increases vapor pressure
Rationale: Higher temperature increases evaporation potential.
9. What is the psychrometric definition of grains?
A. Weight of liquid water
B. Relative humidity scale
C. Mass of water vapor per pound of dry air
D. Condensation rate
ANS >> C. Mass of water vapor per pound of dry air
Rationale: Grains quantify absolute moisture.
10. Why is RH alone unreliable for drying decisions?
A. It fluctuates constantly
B. It ignores temperature
C. It ignores airflow
D. It measures surface moisture
ANS >> B. It ignores temperature
Rationale: RH without temperature lacks context.
11. Which drying phase removes bound water?
A. Extraction
B. Constant rate
C. Falling rate
D. Migration
ANS >> C. Falling rate
Rationale: Bound water removal occurs during falling rate.
, IICRC WATER RESTORATION TECHNICIAN
12. What occurs if evaporation exceeds dehumidification?
A. Faster drying
B. Condensation risk
C. Lower RH
D. Stable grain depression
ANS >> B. Condensation risk
Rationale: Moisture accumulates in the air.
13. Which material has the highest EMC?
A. Concrete
B. Hardwood
C. Gypsum board
D. Carpet fiber
ANS >> A. Concrete
Rationale: Concrete stores large amounts of bound moisture.
14. What does “latent heat” refer to?
A. Sensible temperature change
B. Energy used to move air
C. Energy required to change water phase
D. Heat loss through walls
ANS >> C. Energy required to change water phase
Rationale: Evaporation requires latent heat.
15. Which reading indicates risk of secondary damage?
A. Stable RH
B. Moisture above dry standard
C. Ambient temperature of 22°C
D. Neutral pressure
ANS >> B. Moisture above dry standard
Rationale: Elevated moisture leads to damage.
