IICRC S500 Water Mitigation Exam Preparation Kit
2025/26 | Authentic and Verified Answers
The homeowner - is responsible to take the necessary steps to preserve and protect their
property from further damage
Four principles of water damage restoration: - Provide for health and safety of workers
and occupants; Document everything; Mitigate, and Dry
Four principles of drying - Extract, Evaporate, dehumidify, control temp
Extraction - is removing excess water and is the first step in mitigation
Evaporation - is achieved by using energy (heat) to transform water trapped in porous
materials into a vapor, thereby releasing the moisture from the materials.
Dehumidification - the process of removing water vapor from the air.
Rate of Dehumidification - must be at least equal to the rate of evaporation.
True or False - Elevated vapor pressure in a room Can cause secondary damage to
hygroscopic materials
True or False - The control of temperature is important to enhance both evaporation and
dehumidification for effective drying
True or False - When temperature increases evaporation of absorbed water increases and
water vapor suspended in air also increases.
Classification of Water Intrusion - described as Class 1, 2, 3, or 4. Must be determined to
calculate the amount of dehumidification required in drying process, based on the amount of
wet surface area, permeance/porosity of materials in drying area.
Class 1 - is the least amount of water absorption and evaporation load, affecting less 5%
of porous materials with minimal absorption into low evaporation materials.
Class 2 - has a significant amount of water absorption and evaporation load, affection 5-
40% porous materials, with minimal absorption into low evaporated materials
Class 3 - has the greatest amount of water absorption and evaporation load, affecting
more than 40% porous materials and minimal absorption into low evaporated materials
, Class 4 - has deeply held or bound water, and significant absorption into low evaporation
materials.
Determine the Class of water for a 20' x 20' x 8 ' room, with an entirely wet floor.. -
Affected area/Total SF = % affected
400/1440 = .27777 x 100 = 28%
28% = Class 2
Determine the Class of Water for a 20' x 20' x 8' room, with only half the floor affected and
arriving within 24 hours of loss. - Affected area/total sf = % affected
200/1440 = .13888 x 100 = 14%
14% = Class 2
Determine Class of water for a 20' x 20' x 8' room, with entirely wet plywood subfloor arriving
48 hours after loss - affected area/total sf = % affected
Class 4 due to deeply bound water sitting for long time
Categories of Water - there are four categories - determined by range of contamination
of the source and quality of water
Category 1 water - Water originating from sanitary water source, with no deterioration,
does not pose risk to skin or if ingested
Category 2 Water - Water containing significant contamination from materials, unsafe
levels of microorganisms, causes discomfort or sickness.
Category 3 Water - Water grossly contaminated with pathogens, toxins, bacteria, causes
sickness
Regulated or Hazardous Material and Mold - the last category of water, without number
designation, requiring a specialized environmental expert (EIP) to assist where government
regulations apply.
The ANSI/IICRC S500 - Is the standard of care for the water damage restoration industry,
providing foundation for basic principles of proper restoration practices.
When the ANSI/IICRC S500 uses the word "Shall" it means - it is something mandatory
due to laws/regulations
2025/26 | Authentic and Verified Answers
The homeowner - is responsible to take the necessary steps to preserve and protect their
property from further damage
Four principles of water damage restoration: - Provide for health and safety of workers
and occupants; Document everything; Mitigate, and Dry
Four principles of drying - Extract, Evaporate, dehumidify, control temp
Extraction - is removing excess water and is the first step in mitigation
Evaporation - is achieved by using energy (heat) to transform water trapped in porous
materials into a vapor, thereby releasing the moisture from the materials.
Dehumidification - the process of removing water vapor from the air.
Rate of Dehumidification - must be at least equal to the rate of evaporation.
True or False - Elevated vapor pressure in a room Can cause secondary damage to
hygroscopic materials
True or False - The control of temperature is important to enhance both evaporation and
dehumidification for effective drying
True or False - When temperature increases evaporation of absorbed water increases and
water vapor suspended in air also increases.
Classification of Water Intrusion - described as Class 1, 2, 3, or 4. Must be determined to
calculate the amount of dehumidification required in drying process, based on the amount of
wet surface area, permeance/porosity of materials in drying area.
Class 1 - is the least amount of water absorption and evaporation load, affecting less 5%
of porous materials with minimal absorption into low evaporation materials.
Class 2 - has a significant amount of water absorption and evaporation load, affection 5-
40% porous materials, with minimal absorption into low evaporated materials
Class 3 - has the greatest amount of water absorption and evaporation load, affecting
more than 40% porous materials and minimal absorption into low evaporated materials
, Class 4 - has deeply held or bound water, and significant absorption into low evaporation
materials.
Determine the Class of water for a 20' x 20' x 8 ' room, with an entirely wet floor.. -
Affected area/Total SF = % affected
400/1440 = .27777 x 100 = 28%
28% = Class 2
Determine the Class of Water for a 20' x 20' x 8' room, with only half the floor affected and
arriving within 24 hours of loss. - Affected area/total sf = % affected
200/1440 = .13888 x 100 = 14%
14% = Class 2
Determine Class of water for a 20' x 20' x 8' room, with entirely wet plywood subfloor arriving
48 hours after loss - affected area/total sf = % affected
Class 4 due to deeply bound water sitting for long time
Categories of Water - there are four categories - determined by range of contamination
of the source and quality of water
Category 1 water - Water originating from sanitary water source, with no deterioration,
does not pose risk to skin or if ingested
Category 2 Water - Water containing significant contamination from materials, unsafe
levels of microorganisms, causes discomfort or sickness.
Category 3 Water - Water grossly contaminated with pathogens, toxins, bacteria, causes
sickness
Regulated or Hazardous Material and Mold - the last category of water, without number
designation, requiring a specialized environmental expert (EIP) to assist where government
regulations apply.
The ANSI/IICRC S500 - Is the standard of care for the water damage restoration industry,
providing foundation for basic principles of proper restoration practices.
When the ANSI/IICRC S500 uses the word "Shall" it means - it is something mandatory
due to laws/regulations
