Deck 12: Room Acoustics

Question 1

Presbycusis is:

A)Hearing loss due to long term exposure to noise above 90 dBA
B)Normal deterioration in hearing due to ageing
C)Hearing loss due to ear disease
D)A church presbytery committee
E)Temporary shift in hearing ability from exposure to high industrial noise levels above 95 dBC

Answer 1

B

Question 2

Hearing range is:

A)20 Hz to 20 kHz
B)2 Hz to 20 MHz
C)200 Hz to 200 MHz
D)Infinitely wide
E)2 kHz to 20 MHz

Answer 2

A

Question 3

What does the building services engineer do with noise?

A)Passes any problem to a specialist
B)Ignores it
C)Controls it to acceptable standard in occupied spaces
D)Not select plant that generates noise
E)Alters the use of the building to avoid any noise problem

Answer 3

C

Question 4

Sound travels through air in the form of:

A)Sinusoidal alternating frequency
B)Straight lines
C)Electromagnetic radiation
D)Waves
E)Molecular vibration

Question 5

Reference point for sound level measurement is:

A)Lowest audible level by a domestic animal
B)Absolute zero sound
C)Smallest sound detectable by human ear
D)Zero atmospheric pressure as found in space
E)Inaudible level created in a test laboratory

Question 6

A gas turbine rotates at 60000 RPM and has fifty blades on its largest diameter. One of the sound frequencies it produces is around:

A)50 kHz
B)50 Hz
C)5000 Hz
D)60 kHz
E)20 kHz

Question 7

Which item of plant does not normally create noise?

A)Air compressors
B)Fans and pumps
C)Refrigeration compressors
D)Fired water heaters
E)Piped systems

Question 8

Which is the smallest increment of sound pressure level detectable by the human ear?

A)1 W/m²
B)1 decibel
C)1 Bel
D)60 Bel
E)100 N/m²

Question 9

Explain the meaning of SWL:

A)Sound pressure level, meaning energy
B)Selective wind loading
C)Sound wind level
D)Sound watts level, meaning power
E)Sound watts loudness, meaning loudness power

Question 10

A noisy machine on a plant room concrete floor:

A)May direct sound more strongly in a particular direction
B)Has no sound directivity
C)Sends direct sound field through the floor
D)Only creates a reverberant sound field
E)Gains a benefit from sound energy absorbed by the floor