5.1 Noise

Written by Imran Qureshi (NEBOSH)

NEBOSH IGC · Workplace hazards · 15 questions

Name: ____________________ Date: ____________

Which is a basic noise control measure at the source?
- A Signs
- B Earmuffs
- C Silencing or damping
- D Rotating workers
dB(A) is a scale:
- A For radiation
- B For temperature
- C Used for vibration
- D Weighted to match the human ear
A limitation of hearing protection is:
- A It improves communication
- B Poor fit and discomfort can reduce use
- C It never needs replacing
- D It removes noise completely
Noise damage to hearing is often not noticed at first because it is:
- A Always temporary
- B Always limited to one ear
- C Gradual and painless
- D Always sudden and painful
Tinnitus is:
- A A type of hearing protection
- B A decibel scale
- C A noise measurement
- D Ringing in the ears
The decibel scale is logarithmic, which means that:
- A A small rise in dB is a large rise in energy
- B It cannot be measured
- C Each dB is the same energy
- D It applies only to vibration
The unit of frequency is the:
- A Decibel
- B Lux
- C Pascal
- D Hertz
dB(C) is mainly used to measure:
- A Light levels
- B Peak or very loud sounds
- C Vibration
- D Sounds of low importance
A rough prompt that a noise problem may exist is when people:
- A Work for more than one hour
- B Have a lunch break
- C Wear a hat
- D Have to raise their voices to talk normally at about two metres apart
Noise exposure at work is judged:
- A By the number of machines only
- B By a single reading at the loudest machine
- C Over a working day or week, not by one reading at one machine
- D By asking workers if they like the noise
After eliminating or reducing noise at source, further controls include:
- A Only earplugs
- B Only warning signs
- C Only longer hours
- D Enclosure, absorption, insulation, damping and silencing
Which type of hearing protection has to be chosen according to the attenuation needed?
- A Earmuffs and earplugs
- B Hard hats
- C Gloves
- D Safety glasses
Hearing tests for workers in noisy areas are an example of:
- A Isolation
- B Eliminating the noise
- C Substitution
- D Health surveillance
Which is a limit of hearing protection?
- A It removes the noise at source
- B It lasts for ever
- C It needs no fitting
- D It may make it hard to hear warnings
Which control for noise does not rely on the worker wearing something?
- A Earplugs
- B Enclosing the noisy machine
- C Instruction to wear protection
- D Earmuffs

Answer key

1. C, 2. D, 3. B, 4. C, 5. D, 6. A, 7. D, 8. B, 9. D, 10. C, 11. D, 12. A, 13. D, 14. D, 15. B

Source controls come before hearing protection.
The A weighting reflects the ear's sensitivity.
Hearing protection depends on correct use.
Workers may not notice it until the damage is permanent.
It can result from noise exposure.
Every 3 dB increase roughly doubles the sound energy.
Frequency is the pitch of a sound and is measured in hertz.
dB(A) is used for most workplace measurement.
It is only a prompt to investigate, not a measurement.
Exposure is an average over time.
Hearing protection is the last resort.
Attenuation is the reduction in level that the protection provides.
Health surveillance detects early damage.
Protection also depends on correct fit and use.
Controls at source are more reliable.