Book 2: 1-10 - "Humidification"

Question 1

One of the wetted element humidifiers group is the _____ type.
Select one:

A. Wet

B. Pan

C. Spray

D. Steam

E. Power

Answer 1

E. Power

Question 2

Calculate the relative humidity of a sample of air that at 21°C (70°F) holds 0.014 kg (0.031 lb) of moisture if the maximum that it can hold at this temperature is 0.015 kg (0.033 lb).
Select one:

A. 93.3%

B. 6.7%

C. 10.7%

D. 0.33%

E. 25.8%

Answer 2

A. 93.3%

Question 3

Atomizing humidifiers have the disadvantage that:
Select one:

A. The water sprayed into the air evaporates leaving the salts that appear as a fine white dust

B. They have no moving parts

C. They add moisture to the air

D. They have no float valve

E. They do not require a motor

Answer 3

A. The water sprayed into the air evaporates leaving the salts that appear as a fine white dust

Question 4

When the air washer is used for humidification, the spray water must be _____ temperature of the entering air.
Select one:

A. Cooled below the wet bulb

B. Heated above the dry bulb

C. Cooled below the dry bulb

D. Cooled below the dew point

E. Heated above the dew point

Answer 4

E. Heated above the dew point

Question 5

The steam heated pan humidifier offers high capacity and accurate humidity control if used with a modulating control valve and steam pressure not exceeding:
Select one:

A. 10 kPa (1.5 psi)

B. 160 kPa (23.2 psi)

C. 103 kPa (15 psi)

D. 130 kPa (19 psi)

E. 50 kPa (7.3 psi)

Answer 5

C. 103 kPa (15 psi)

Question 6

Calculate the relative humidity of a sample of air that at 21°C (70°F) holds 0.01 kg (0.022 lb) of moisture if the maximum that it can hold at this temperature is 0.015 kg (0.033 lb).
Select one:

A. 25.8%

B. 93.3%

C. 6.7%

D. 0.33%

E. 10.7%

Answer 6

C. 6.7%
BAD QUESTION - ANSWER SHOULD BE 66.7%

Question 7

When the air temperature is raised without a change in moisture content the relative humidity will:
Select one:

A. Decrease

B. Not change

C. Increase

D. Gain latent heat

E. Lose latent heat

Answer 7

A. Decrease

Question 8

The pan type humidifier has a/an:
Select one:

A. High humidification rate

B. Very High humidification rate

C. Moderate humidification rate

D. Very low humidification rate

E. Low humidification rate

Answer 8

D. Very low humidification rate

Question 9

Calculate the relative humidity of a sample of air that at 21°C (70°F) holds 0.01 kg (0.022 lb) of moisture if the maximum that it can hold at this temperature is 0.015 kg (0.033 lb).
Select one:

A. 93.3%

B. 66.7%

C. 25.8%

D. 10.7%

E. 0.33%

Answer 9

B. 66.7%

Question 10

The steam pressure on a steam grid humidifier should be in the range of:
Select one:

A. 40 kPa to 55 kPa (5.8 to 8 psi)

B. 35 kPa to 70 kPa (5.1 to 10.2 psi)

C. 25 kPa to 45 kPa (3.6 to 6.5 psi)

D. 20 kPa to 30 kPa (2.9 to 4.4 psi)

E. 30 kPa to 60 kPa (4.4 to 8.7 psi)

Answer 10

B. 35 kPa to 70 kPa (5.1 to 10.2 psi)

Question 11

One of the types of humidifiers used for residential purposes is the _____ humidifier.
Select one:

A. Air washer

B. Steam

C. Dry element

D. Pan

E. Pot

Answer 11

D. Pan

Question 12

One of the types of humidifiers used for residential purposes is the _____ humidifier.
Select one:

A. Dry element

B. Steam

C. Atomizing

D. Pot

E. Air washer

Answer 12

C. Atomizing

Question 13

Relative humidity is the amount of _____ expressed as a percentage.
Select one:

A. Air contained in the moisture compared to the minimum amount of moisture the air is capable of holding at the stated temperature

B. Moisture contained in the air compared to the maximum amount of moisture the air is capable of holding at any temperature

C. Moisture contained in the air compared to the maximum amount of moisture the air is capable of holding at the stated temperature

D. Air contained in the moisture compared to the maximum amount of moisture the air is capable of holding at the stated temperature

E. Moisture contained in the air compared to the minimum amount of moisture the air is capable of holding at the stated temperature

Answer 13

C. Moisture contained in the air compared to the maximum amount of moisture the air is capable of holding at the stated temperature

Question 14

When the air temperature is lowered without a change in moisture content the relative humidity will:
Select one:

A. Decrease

B. Not change

C. Lose latent heat

D. Increase

E. Gain latent heat

Answer 14

D. Increase

Question 15

The humidification process refers to adding _____ to the air.
Select one:

A. Heat

B. Enthalpy

C. Water vapour or moisture

D. Temperature

E. Steam

Answer 15

C. Water vapour or moisture

Question 16

An air washer is installed on the suction side of the fan so as to:
Select one:

A. Avoid leakage of water through the joints

B. Add sensible heat to the air

C. Avoid leakage of air through the joints

D. Add latent heat to the air

E. Add moisture to the air

Answer 16

A. Avoid leakage of water through the joints

Question 17

When the air washer is used for dehumidification, the spray water must be _____ temperature of the entering air.
Select one:

A. Heated above the dry bulb

B. Cooled below the dew point

C. Heated above the dew point

D. Cooled below the wet bulb

E. Cooled below the dry bulb

Answer 17

B. Cooled below the dew point

Question 18

One of the types of humidifiers used for residential purposes is the _____ humidifier.
Select one:

A. Dry element

B. Steam

C. Pot

D. Wetted element

E. Air washer

Answer 18

D. Wetted element

Question 19

From a health standpoint, humidity between _____ is desirable.
Select one:

A. 15% and 30%

B. 25% and 40%

C. 45% and 60%

D. 55% and 80%

E. 35% and 50%

Answer 19

E. 35% and 50%

Question 20

Calculate the relative humidity of a sample of air that at 21°C (70°F) holds 0.005 kg (0.011 lb) of moisture if the maximum that it can hold at this temperature is 0.015 kg (0.033 lb).
Select one:

A. 10.7%

B. 93.3%

C. 6.7%

D. 25.8%

E. 0.33%

Answer 20

E. 0.33%
Answer should be 33%