Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024
IICRC - Applied Structural Drying Exam
Questions and Answers
Air Filtration Device (ADF) - ANSWER✔✔-Commonly called an air scrubber or negative air machine if
airborne particles need to be reduced, you could use an appropriately installed _______ ________
________
Air Filtration Device - ANSWER✔✔-AFD
Assembly Construction - ANSWER✔✔-Prior to determining the best drying system for affected materials,
restorers should identify and understand the assembly construction (ie wall assembly, floor assembly)
Category 1 - ANSWER✔✔-water originates from a sanitary source and does not pose substantial risk for
dermal, ingestion, inhalation, or exposure. Uncontaminated and routinely cleaned
Category 2 - ANSWER✔✔-water contains significant contamination and has the potential to cause
discomfort or sickness if contacted or consumed by humans
Category 3 - ANSWER✔✔-water is grossly contaminated and can contain pathogenic, toxigenic, or other
harmful agents
Sewage Back Up - ANSWER✔✔-Category 3
Clean water supply line - ANSWER✔✔-Category 1
Class 1 - ANSWER✔✔-Least amount of water absorption and evaporation load - Wet porous materials -
water loss is less then 5% of the area
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Class 2 - ANSWER✔✔-Significant amount of water absorption and evaporation load - water intrusion
where wet represents 5% - 40% of the area.
Class 3 - ANSWER✔✔-greatest amount of water absorption and evaporation load. Water intrusion where
wet represents over 40% of the area
Class 4 - ANSWER✔✔-deeply held or bound water. Significant amount of water absorption into low
evaporation materials. Drying may require special drying methods, longer drying time, or substantial
water vapor pressure differentials.
Closed drying system - ANSWER✔✔-Uses mechanical dehumidification and is not open to outside air.
Used if there are security issues, the outside air is not conductive to drying or when access to outside air
is not possible.
Conventual refrigerant dehumidifier - ANSWER✔✔-Removes water vapor from the air by lowering the
temperature of the incoming air to below dew point and causing the water to condense on the coils.
Cold and hot surfaces created with gases inside a closed coil system.
Combination Drying System - ANSWER✔✔-uses some outdoor air with dehumidifiers to accelerate the
drying process. This can include periodically venting (flushing) the structure, using negative pressure or
using small openings to the outside
Desiccant dehumidifier - ANSWER✔✔-Removes water vapor from the air through absorption. Usually
requires more amperage as compared to refrigerant dehumidifier. Desiccants create the lowest vapor
pressure which work best on low porosity materials. When a desiccant dehu is drawing outside air and
ducting processed air inside a building it can create positive pressure in the building. To improve
desiccant dehu performance, it may be beneficial to pre-cool the desiccants air intake
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Infiltration - ANSWER✔✔-High humidity outside air could affect the drying climate adversely due to
______________
1. Tightness of the building envelope
2. Prevailing weather
3. HVAC
4. Class of Water
5. Building Construction
5. Build out density - ANSWER✔✔-Favors that affect the detailed dehumidifier calculation is:
Detailed Dehumidification Calculation - ANSWER✔✔-See Chart:
Cubic Feet : Divided by 70 = Base Pints per day
Multiply the 5 multipliers together: Build out density x building construction x class of water x HVAC x
Weather Impact = Multiplier
Multiply Base Pints per day x Multiplier = Adjusted Pints Per Day
Dry Standards - ANSWER✔✔-The unaffected material readings are called ______ ______. You know you
can use this as your drying goal. Your drying goal is this plus 10% of it.
Drying Goal Calculation - ANSWER✔✔-Dry standard + (Dry standard x 10%) = ____________________
Why does demolition occur - ANSWER✔✔-1. Removing Materials to eliminate safety hazards
2. Removing materials that have suffered primary damage and are not restorable
3. Removing porous materials that are holding odor
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IICRC - Applied Structural Drying Exam
Questions and Answers
Air Filtration Device (ADF) - ANSWER✔✔-Commonly called an air scrubber or negative air machine if
airborne particles need to be reduced, you could use an appropriately installed _______ ________
________
Air Filtration Device - ANSWER✔✔-AFD
Assembly Construction - ANSWER✔✔-Prior to determining the best drying system for affected materials,
restorers should identify and understand the assembly construction (ie wall assembly, floor assembly)
Category 1 - ANSWER✔✔-water originates from a sanitary source and does not pose substantial risk for
dermal, ingestion, inhalation, or exposure. Uncontaminated and routinely cleaned
Category 2 - ANSWER✔✔-water contains significant contamination and has the potential to cause
discomfort or sickness if contacted or consumed by humans
Category 3 - ANSWER✔✔-water is grossly contaminated and can contain pathogenic, toxigenic, or other
harmful agents
Sewage Back Up - ANSWER✔✔-Category 3
Clean water supply line - ANSWER✔✔-Category 1
Class 1 - ANSWER✔✔-Least amount of water absorption and evaporation load - Wet porous materials -
water loss is less then 5% of the area
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,Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024
Class 2 - ANSWER✔✔-Significant amount of water absorption and evaporation load - water intrusion
where wet represents 5% - 40% of the area.
Class 3 - ANSWER✔✔-greatest amount of water absorption and evaporation load. Water intrusion where
wet represents over 40% of the area
Class 4 - ANSWER✔✔-deeply held or bound water. Significant amount of water absorption into low
evaporation materials. Drying may require special drying methods, longer drying time, or substantial
water vapor pressure differentials.
Closed drying system - ANSWER✔✔-Uses mechanical dehumidification and is not open to outside air.
Used if there are security issues, the outside air is not conductive to drying or when access to outside air
is not possible.
Conventual refrigerant dehumidifier - ANSWER✔✔-Removes water vapor from the air by lowering the
temperature of the incoming air to below dew point and causing the water to condense on the coils.
Cold and hot surfaces created with gases inside a closed coil system.
Combination Drying System - ANSWER✔✔-uses some outdoor air with dehumidifiers to accelerate the
drying process. This can include periodically venting (flushing) the structure, using negative pressure or
using small openings to the outside
Desiccant dehumidifier - ANSWER✔✔-Removes water vapor from the air through absorption. Usually
requires more amperage as compared to refrigerant dehumidifier. Desiccants create the lowest vapor
pressure which work best on low porosity materials. When a desiccant dehu is drawing outside air and
ducting processed air inside a building it can create positive pressure in the building. To improve
desiccant dehu performance, it may be beneficial to pre-cool the desiccants air intake
Copyright ©Stuvia International BV 2010-2024 Page 2/18
, Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024
Infiltration - ANSWER✔✔-High humidity outside air could affect the drying climate adversely due to
______________
1. Tightness of the building envelope
2. Prevailing weather
3. HVAC
4. Class of Water
5. Building Construction
5. Build out density - ANSWER✔✔-Favors that affect the detailed dehumidifier calculation is:
Detailed Dehumidification Calculation - ANSWER✔✔-See Chart:
Cubic Feet : Divided by 70 = Base Pints per day
Multiply the 5 multipliers together: Build out density x building construction x class of water x HVAC x
Weather Impact = Multiplier
Multiply Base Pints per day x Multiplier = Adjusted Pints Per Day
Dry Standards - ANSWER✔✔-The unaffected material readings are called ______ ______. You know you
can use this as your drying goal. Your drying goal is this plus 10% of it.
Drying Goal Calculation - ANSWER✔✔-Dry standard + (Dry standard x 10%) = ____________________
Why does demolition occur - ANSWER✔✔-1. Removing Materials to eliminate safety hazards
2. Removing materials that have suffered primary damage and are not restorable
3. Removing porous materials that are holding odor
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