WRT Review Questions

RTI file

What is the most important aspect to any job?

Safety of all individuals involved

What is one of the most common safety concerns on a water damage project?

Slip and fall

What does safety in water damage restoration include?

All the above

What are your first responsibilities when arriving on a jobsite?

Identify, communicate, and eliminate (when possible) all safety hazards

What must employers provide to any employee working in a respirator?

All the above

When do water damage mitigation services start?

After a work authorization (contract) has been signed

During the initial inspection, what areas should be checked for water damage?

All areas that could potentially be affected

Are lead and asbestos, commonly found in older structures, hazardous materials regulated by the Federal government?

True

What does the Category of water refer to?

The range of contamination in water, considering both its originating source and its quality after contacting materials on the jobsite

What category is water that has a significant degree of contamination and could cause illness?

Category 2

What category is grossly contaminated water?

Category 3

If stopped from removing highly porous materials affected by a Category 3 loss, what should the restorer do?

Stop work to prevent liability

Does improperly performing work on a Category 3 water loss pose serious liability concerns?

True

What category is water that contains diesel fuel?

Regulated, Hazardous Materials or Mold

What criteria determine whether contents or materials should be saved?

All the above

What are the three types of damage a technician needs to identify, document, and communicate?

Pre-existing, primary, secondary

Above what relative humidity can secondary damage occur?

60%

What is an important result of the initial extraction?

Keep the water from migrating

What does thorough or multiple extraction accomplish?

Reduces drying times

How should water extracted from a jobsite be disposed of?

According to local laws

How many gallons are in one cubic foot of water?

7.48 gallons

What is the formula to calculate gallons of water?

Length × Width × Depth × 7.48

How many gallons are in a 25' × 30' basement with 9" of standing water?

4,208 gallons

How many gallons are in a 12' × 15' crawlspace with 5'3" of standing water?

7,069 gallons

What is a moisture reading from an unaffected material used to set drying goals called?

Dry standard

When is a drying job done?

When a moisture meter indicates we have met our dry goal

Can a moisture sensor be used to verify that a drying goal has been met?

False

What can give false moisture readings when using a non-penetrating meter?

All the above

What are moisture sensors and IR cameras effective tools for?

Quickly locating moisture in carpet and pad and establishing a wet perimeter

What does a thermo-hygrometer measure?

Temperature and relative humidity

Why do infrared cameras indicate possible moisture in materials?

Materials surface temperature cools as water evaporates

Once an area is identified by an infrared camera as a possible wet area, what must verify it?

A moisture meter or sensor

Do psychrometric conditions directly affect the rate at which moisture moves within and from materials?

True

What are the three things restorers can manipulate to promote drying (the drying pie)?

Humidity, Airflow, Temperature

What is the ratio of moisture in air compared to the maximum amount the air could hold at that temperature?

Relative Humidity

What is the ratio of the weight of water vapor mixed with dry air called?

Humidity Ratio

How is Humidity Ratio measured and expressed?

Grains Per Pound

The ______ difference between the dew point temperature of surrounding air and the temperature of the affected material (if warmer), the greater the potential for drying.

Greater

What do restorers need to control to promote effective drying?

All the above

What may lowering the temperature in a drying chamber cause?

Condensation

If you increase the temperature in a drying chamber, what happens to relative humidity?

Decrease

Evaporation will increase when what happens?

All the above

What happens at dew point temperature?

Vapor changes to liquid

What causes the movement of water vapor through a material?

Vapor pressure differentials

If trying to save wet documents, what should you do to stop further damage?

Freeze them

What is the process of changing a solid (ice) into a vapor without going through the liquid phase?

Sublimation

The greater the temperature of wet materials, the more energy is available for what to occur?

Evaporation

If a drying chamber is 75°F and 40% RH, what is the humidity ratio?

52 gpp

If a drying chamber is 68°F and 70% RH, what is the humidity ratio?

72 gpp

If a drying chamber is 70°F and 60 gpp, what is the RH?

55%

If the exterior is 42°F and 30% RH, what is the humidity ratio?

12 gpp

If a drying chamber is 32% RH and 60 gpp, what is the temperature?

87°F

Starting at 70°F and 60% RH, what temperature would you need to reach 40% RH?

82°F

What is the relative humidity if the dew point is 35°F and the dry bulb temperature is 70°F?

28%

What material is very weakened when wet but regains its original strength if dried properly?

Gypsum (drywall, wallboard, sheetrock)

What material is generally removed when wet or damaged?

Particle board

What is the ability for water vapor to move through materials called?

Permeability

What determines the volume of moisture a material may absorb?

Porosity

What do Classes of water describe?

The potential rate of evaporation (evaporation load)

What is a drying chamber with less than 5% of the combined walls, floors, and ceiling materials affected?

Class 1

What percentage of combined walls, floors, and ceiling materials are significantly affected in a Class 2 loss?

5%-40%

What class has the greatest amount of moisture, affecting over 40% of the combined walls, floors, and ceiling materials?

Class 3

What class has water bound in materials such as plaster or hardwood, resulting in low potential evaporation?

Class 4

When attempting to dry tile over a wood subfloor, what should a restorer do?

Both B and C

What safety feature does drying equipment need?

Grounded plug

What can happen when ducting airflow directly into wall cavities?

Increases the rate of evaporation

In addition to the required initial air mover, how many air movers should be added for affected wet floor and affected wet ceiling/walls above two feet?

One for every 50-70 square feet of affected wet floor and one for every 100-150 square feet of affected wet ceiling/walls above two feet

For each wall inset and offset greater than how many inches should one air mover be added?

18 inches

Where water migration primarily affects lower wall sections with less than 24" affected flooring, how many linear feet does each air mover cover?

14 linear feet

A balanced drying system is best achieved when the rate of dehumidification is ______ than or equal to the rate of evaporation.

Greater

How do refrigerant dehumidifiers remove moisture from the air?

Condensation

What are refrigerant dehumidifiers rated for water removal in?

Pints per Day (PPD)

Through what principle do desiccant dehumidifiers remove moisture from the air?

Adsorption

How are desiccant dehumidifiers rated?

Cubic Feet per Minute (CFM)

Desiccant dehumidifiers are not limited by what because they do not remove water vapor through condensation?

Temperature

In an area measuring 15,000 cubic feet, what is the initial AHAM requirement for a Class 2 loss using an LGR dehumidifier?

300

A Class 3 loss measuring 15' × 35' with a 9' ceiling requires how many 100-pint LGRs?

2

A 35' × 40' × 10' warehouse with a Class 4 loss using a desiccant dehumidifier requires how many CFM?

700 CFM

What can be installed to control particles in the air?

An air filtration device (AFD)

Hardwood products should be within what percentage of the dry standard?

2-4% of the dry standard

What is the physical balance found in nature?

Equilibrium

What can cause carpet delamination?

Bending, folding or improper removal from tack strip

What is the purpose of the skin or membrane on most carpet pad?

To aid in carpet installation

How should carpet seams be cut?

Only as necessary

What should be used to properly disengage carpet from a tack strip?

Knee kicker and carpet awl

How should a wood subfloor under a vinyl floor generally be dried?

Remove vinyl to dry the subfloor

What is it called when a hardwood floor primarily absorbs moisture from the bottom and sides, causing the edges to be higher than the center?

Cupping

What moisture content level and above may allow fungal rot to occur in wood?

20%

What is the most important factor in minimizing damage when a water loss occurs?

Rapid response to start mitigation procedures

Who could complete an assessment on a project with significant mold growth or Category 3 water?

An Indoor Environmental Professional (IEP)

When applying an antimicrobial (biocide), what should restorers do?

All the above

Which product would reduce microorganisms to a level considered safe by public health standards?

Sanitizer

What should the restorer document during initial and ongoing inspections?

Psychrometric readings and moisture content readings

How can drying times of affected materials be decreased?

Increasing evaporation by installing air movers and adding thermal energy

When should carpet pad always be disposed of?

When affected by Category 2 or 3 water

How should elevated moisture under tile or behind vinyl wallpaper be checked?

Use a non-penetrating or non-invasive moisture meter

When should drywall always be removed due to safety concerns?

When the drywall on the ceiling is affected and sagging

If vapor pressure decreases, what happens to GPP?

Decreases

When arriving at a water loss with high relative humidity, what could reduce the humidity?

Open the windows to ventilate the structure (if outside conditions are favorable)

When could a closed drying system be utilized?

When the GPP (Humidity Ratio) outside is higher than the GPP indoors