C2- Reverberation Time, Airborne, Impact, & Flanking Sound

Question 1

What are the 3 features of sound waves?
1.
2.
3.

Answer 1

1. Wavelength
2. Frequency
3. Amplitude

Question 2

What is sound measured in?

Answer 2

Decibels. (dB).

Question 3

Reverberation time is the time a sound ___________ and can be heard by a listener.

Answer 3

persists

Question 4

The equation for reverberation time is:
Reverberation time= _______________________

Answer 4

Reverberation time= 0.16 x volume/ absorption

Question 5

Airborne sound is produced ___________ into the air.

Impact sound is produced by the _____________ of objects.

Answer 5

directly
vibration

Question 6

How can airborne sound outside affect buildings?

Airborne sounds can pass through _______ in a building’s structure which will create ______________________________________.

Answer 6

gaps
excessive noise inside the building

Question 7

How can airborne sound outside affect buildings?

Vibrations can cause ___________________ so a building may need more _________________________.

Answer 7

building damage
frequent maintenance

Question 8

Flanking noise is the noise reaching a room by an _______________.

Answer 8

indirect path

Question 9

How do you make a building more sound-proof?
1. Consider the __________ of the sound
2. Improving _____________________ in the building.
3. Controlling the ___________________.
4. Using sound reducing _____________.

Answer 9

1. source
2. structural elements
3. flanking sound
4. materials

Question 10

What is the 3 stage approach to sound insulation called?

Answer 10

Source-path-receiver approach.

Question 11

How can the source-path-receiver approach reduce sound to protect workers in a health-centre?

The source of the sound can be considered first when designing the building’s sound insulation by installing sound insulation in rooms that cause the most vibrations or noise. This may be an operational room with noisy machinery. This room must be installed with the highest level of sound insulation using sound absorbent materials such as fibreglass insulation. The materials used for the structure of the building can be considered as gaps in the structure of the building may be the path for sound to spread.

Answer 11

Source- Equipment in a plant room will generate noise. Silencers can be fitted.

Path- The most dominant noise path should be analysed.

Receiver- Barriers can be fitted to divert noise away from the receiver.

Use high mass materials.
Modify employee work patterns.

Question 12

How can flanking sound be reduced in a college building?

________________ can be installed _________________ to prevent sound from ____________ through ______ between rooms.

Answer 12

Insulation
around doors
travelling
gaps

Question 13

The flanking sound through single glazed windows can be reduced by installing _______________________.

Answer 13

double glazed windows

Question 14

What is a sound reduction index?

Answer 14

The measure of insulation of airborne sound.

Question 15

What is a weighted sound reduction index?

Single measure of insulation of airborne sound over a __________________.

Answer 15

range of frequencies

Question 16

Why might sound reduction indices be calculated for new houses?

To ensure there is sufficient _________________.
To meet _________________.

Answer 16

acoustic insulation
acoustic regulations

Question 17

Does carpeting reduce impact sound?

Answer 17

Yes.

Question 18

Sound insulation involves ________.
Sound absorption involves more general __________.

Answer 18

barriers
materials

Question 19

Sound insulation requires ______ materials.
Sound absorption requires _______ materials.

Answer 19

dense
porous

Question 20

An architect is designing an apartment block.
What are 3 things to consider in the design process:
1.
2.
3.

Answer 20

1. Bedroom placements within the internal design.
2. Sealing gaps in the structure.
3. Building regulations for party walls.

Question 21

What are the reasons for sound insulation/ reduction in a mixed used building:
1. Prevent ____________________.
2. Prevent ______________________.
3. Prevent noise from ___________ from one space to another.
4. Prevent ___________ from passing through building.
5. Increases __________________.

Answer 21

low frequency noise
potential for vibrations
passing
echoes
confidentiality

Question 22

Low frequency sound decreases people’s _____________.

High frequency sound causes _________________ through headaches.

Answer 22

concentration

short-term discomfort

Question 23

Considering noise criteria indices when designing a new building:

Comfortable levels of noise _________________________, so different ______________ must be used to control the different noise levels.

Answer 23

differ between rooms
materials

Question 24

Considering noise criteria indices when designing a new building:

_______________________ set performance standards for noise levels.
So ________________________ are required to meet these standards.

Answer 24

Building regulations

appropriate materials