Chapter 128

Question 1

Static pressure up to 1.50 kPa/ Velocities 11 m/s -25 m/s

Answer 1

Medium Pressure duct system

Question 2

Improperly designed duct systems will act as a large ___________

Answer 2

bull born

Question 3

Static pressure not exceeding 0.50 kPa/Velocities less than 11 m/s

Answer 3

Low pressure duct system

Question 4

Static pressure 1.50-2.50 kPa/Velocity greater than 25 m/s

Answer 4

High pressure

Question 5

Duct materials are fabricated of?

Answer 5

sheet metal, plastic, cement asbestos or fibreglass

Question 6

The materials used in sheet metal duct systems are:

Answer 6

galvanized steel, black steel, aluminum, stainless steel and copper

Question 7

Normal services involves only atmospheric contaminants and localized water carryover from cooling coils, humidifiers, air washers, or outdoor air intakes

Answer 7

galvanized steel

Question 8

Used for kitchen exhaust ducts

Answer 8

black steel

Question 9

the cost is justified by the need for maximum resistance to moisture.

Answer 9

Aluminum, stainless steel, copper

Question 10

Exhaust of corrosive material, such as from laboratory fume hoods

Answer 10

cement asbestos

Question 11

Very light weight, have low initial cost, and naturally silencing.

Answer 11

Fibreglass

Question 12

Changes in duct size should be gradual with a slope of

Answer 12

1 in 7

Question 13

Mitre elbows which have legs of equal length may increase _________

Answer 13

velocity

Question 14

Short radius elbows should be provided with _______

Answer 14

turning vanes

Question 15

Splitters and positive lock dampers should be used on all ________

Answer 15

branch ducts

Question 16

Depending on workmanship, air leakages from ducts vary from ________%

Answer 16

5-30%

Question 17

In regards of duct work, what must be provided at the fan discharge or suction openings?

Answer 17

flexible connectors

Question 18

Functions of terminal air distribution devices are accomplished by what four methods?

Answer 18

diffusion, induction, entrainment, aspiration

Question 19

The air is introduced through a terminal device intro the space in a manner designed to result in rapid mixing of supply air and room air.

Answer 19

diffusion

Question 20

List the three classifications of air conditioning ducts

Answer 20

low pressure, medium pressure, high pressure

Question 21

Short radius elbows should be provided with ____

Answer 21

turning vanes

Question 22

Relief dampers allow air flow in

Answer 22

only one direction