Ch. 3 Environmental Controls

Question 1

Describe dehumidification

Answer 1

The removal of moisture vapor from the air to lower its dew point

Question 2

When planning enclosures, the following minimum requirements should be considered:

Answer 2

Be large enough to contain the whole intended work area

Not be larger than the performance capabilities of the dehumidification equipment

Be strudy enough to hold up to intended work activities, potential loads, and possible inclement weather

Have minimal leakage to maintain proper environmental conditions and ensure the dehumidification system operates efficiently

Question 3

Describe air turns (air changes):

Answer 3

Air turnover or exchanges to to eliminate air stratification

Question 4

At and below what relative humidity does corrosion virtual cease?

Answer 4

40%

Question 5

Describe two ways to reduce the relative humidity of the boundry layer

Answer 5

Increase the surface temperature

Reduce moisture content by dehumidification

Question 6

Types of dehuidification equipments include:

Answer 6

Refrideration and Desiccants

Question 7

Describe several benefits of dehumidification

Answer 7

Crews can begin work earlier in hte day and work later

Eliminates contamination of previously applied coatings by the blasting operation

Eliminates overlaps from one coated surface onto another (during daily blast-then-coat routine)

All coating is done in ideal conditions

Extended over-coating intervals are avoided

Contractor can guarantee, with reasonable accuracy, the completion time

Extends the coating season by many months

Contractor can control ambient conditions despite weather and atmospheric changes