Noise and Vibration Flashcards

What is the lower exposure action value (LEAV) for daily personal noise exposure under Irish health and safety regulations?

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.

When daily noise reaches the upper exposure action value of 85 dB(A), what action must an employer take?

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.

What is the noise exposure limit value (ELV) that must never be exceeded under Irish regulations, even with hearing protection in use?

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.

Which type of hearing protection generally provides the greatest noise attenuation in very high noise environments on a construction site?

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.

What is the most serious long-term health consequence of uncontrolled exposure to excessive noise on a construction site?

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.

According to the hierarchy of control, what is the first and most effective step an employer should take to control noise hazards on site?

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.

What does the 'A' in dB(A) refer to when measuring occupational noise exposure?

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.