Water damage course 46-75

Question 1

In an area that measures 15,000 cubic feet, what is the initial recommended AHAM requirement (PPD) for a Class 2 loss, using LGR (refrigerant) dehumidifiers?

Answer 1

300

Question 2

A Class 3 loss that measures 15’ x 35’ and has a ceiling height of 9’, how many 100-pint LGRs are needed?

Answer 2

2

Question 3

A warehouse that measures 35’ x 40’ x 10’ has a class 4 loss, using a desiccant dehumidifier. How many CFM are required?

Answer 3

700 cfm

Question 4

To help control particles in the air you could install

Answer 4

An air filtration device (AFD)

Question 5

Generally, to dry the wood subfloor under a resilient floor (e.g., sheet vinyl, VCT, LVT, LVP), what should a restorer do?

Answer 5

Remove vinyl to access and dry the subfloor

Question 6

If you decrease GPP what happens to the vapor pressure?

Answer 6

Decreases

Question 7

A hardwood floor primarily absorbing moisture from the bottom and the sides of the boards are higher than the center. This is referred to as

Answer 7

Cupping

Question 8

When arriving on a water loss that has an elevated humidity; if the outside conditions are right, what could be done to reduce the humidity?

Answer 8

Open the windows to ventilate the structure

Question 8

What happens when air reaches saturation?

Answer 8

Condensation because the air can’t hold more water vapor

Question 9

When could a closed drying system be utilized?

Answer 9

When the Humidity Ratio outside is higher than the GPP indoors

Question 10

What happens when the vapor pressure of wet materials is increased?

Answer 10

Moisture evaporates if the ambient air has a lower vapor pressure

Question 11

To determine the amount of dehumidification necessary, the following information is needed:

Answer 11

Cubic footage, class of loss and type of dehumidifier

Question 11

Why should air movers not be installed when microbial growth is found or suspected?

Answer 11

It can contaminate other areas

Question 12

What is evaporation?

Answer 12

Changing liquid to a vapor

Question 13

What is vapor pressure?

Answer 13

The force from water vapor on materials

Question 14

What results as the air becomes warmer (temperature increases)?

Answer 14

Relative humidity decreases

Question 14

When drying a hardwood floor, typically we will need to?

Answer 14

Allow for acclimation and refinishing after the floor is dry

Question 15

If insulation is affected by water, what would be the typical response?

Answer 15

Remove the insulation to access and dry structural materials

Question 16

What is the primary function of a dehumidifier?

Answer 16

Reduce the water vapor in the air

Question 17

Why are desiccant dehumidifiers often used in Class 4 losses?

Answer 17

it creates the lowest vapor pressure of any type of dehumidifier

Question 18

How often should a job site be monitored?

Answer 18

every day

Question 18

If thermal energy is added to affected materials

Answer 18

Evaporation increases

Question 19

If humidity remains high, what can happen to hygroscopic materials?

Answer 19

Secondary damage can occur

Question 20

If plywood is affected by water damage

Answer 20

It can typically be dried and restored

Question 20

In a drying chamber with the conditions of 75°F and 65%RH, at what temperature could condensation form on materials?

Answer 20

62°F

Question 21

Which of the following is a vapor barrier/retarding material?

Answer 21

Vinyl flooring

Question 22

Why are low grain refrigerants (LGR) generally more efficient than a conventional refrigerant?

Answer 22

They create lower vapor pressure

Question 23

A material that is very weakened when wet but, if dried properly, retains its original strength is

Answer 23

Gypsum (drywall, wallboard)

Question 24

What is permeance

Answer 24

The rating of vapor passing through a material

Question 25

If attempting to dry tile over a wood subfloor

Answer 25

Increase heat or thermal energy