CSCS Ireland Noise and Vibration 1 — Questions and Answers
Question 1: What is the lower exposure action value (LEAV) for daily personal noise exposure under Irish health and safety regulations?
- 75 dB(A)
- 80 dB(A) (Correct answer)
- 85 dB(A)
- 90 dB(A)
Correct answer: 80 dB(A)
Under the Safety, Health and Welfare at Work (General Application) Regulations 2007, the lower exposure action value for daily noise is 80 dB(A), at which point employers must begin taking steps such as providing hearing protection on request.
Question 2: When daily noise reaches the upper exposure action value of 85 dB(A), what action must an employer take?
- Simply monitor the noise level and keep records
- Provide hearing protection to workers who request it
- Establish mandatory hearing protection zones and enforce their use (Correct answer)
- Reduce the working day to four hours
Correct answer: Establish mandatory hearing protection zones and enforce their use
At the upper exposure action value of 85 dB(A), employers must establish hearing protection zones, supply appropriate hearing protection, and ensure its mandatory use within those zones.
Question 3: What is the noise exposure limit value (ELV) that must never be exceeded under Irish regulations, even with hearing protection in use?
- 85 dB(A)
- 87 dB(A) (Correct answer)
- 90 dB(A)
- 95 dB(A)
Correct answer: 87 dB(A)
The exposure limit value under the 2007 regulations is 87 dB(A); this is the absolute ceiling and must not be exceeded when account is taken of the attenuation provided by hearing protection.
Question 4: Which type of hearing protection generally provides the greatest noise attenuation in very high noise environments on a construction site?
- Disposable foam earplugs alone
- Reusable pre-moulded earplugs alone
- Earmuffs alone
- A combination of earplugs worn underneath earmuffs (Correct answer)
Correct answer: A combination of earplugs worn underneath earmuffs
Wearing earplugs under earmuffs (dual protection) provides the highest level of noise attenuation and is recommended where noise levels are extreme.
Question 5: What is the most serious long-term health consequence of uncontrolled exposure to excessive noise on a construction site?
- Temporary threshold shift that fully recovers overnight
- Permanent noise-induced hearing loss (NIHL) (Correct answer)
- Mild ringing in the ears lasting one hour
- Increased blood pressure that normalises after work
Correct answer: Permanent noise-induced hearing loss (NIHL)
Noise-induced hearing loss is permanent and irreversible; hair cells in the inner ear that are destroyed by noise cannot regenerate, making prevention the only effective strategy.
Question 6: According to the hierarchy of control, what is the first and most effective step an employer should take to control noise hazards on site?
- Issue hearing protection to every worker immediately
- Erect noise hazard warning signs at the site entrance
- Eliminate or reduce noise at source through engineering or substitution (Correct answer)
- Carry out audiometric testing for all staff
Correct answer: Eliminate or reduce noise at source through engineering or substitution
The hierarchy of control requires elimination or reduction of the hazard at source — for example by using quieter equipment or damping vibrating surfaces — before relying on personal protective equipment.
Question 7: What does the 'A' in dB(A) refer to when measuring occupational noise exposure?
- A frequency weighting that reflects how the human ear perceives sound at different pitches (Correct answer)
- The average sound level measured over a full working week
- The absolute peak sound pressure level recorded
- The amplitude of the sound wave in pascals
Correct answer: A frequency weighting that reflects how the human ear perceives sound at different pitches
The A-weighting filter adjusts measured sound levels to approximate the sensitivity of human hearing across the frequency spectrum, making dB(A) the standard unit for assessing hearing damage risk.
CSCS Ireland Noise and Vibration 1
What is the lower exposure action value (LEAV) for daily personal noise exposure under Irish health and safety regulations?