NEBOSH Workplace Hazards 2

Question 1

What is 'noise-induced hearing loss' (NIHL) and at what exposure level must employers act?

Accepted Answer

NIHL is permanent irreversible hearing damage from excessive noise; the action level requiring controls is 80 dB(A) for daily exposure (lower action value)

Answer

NIHL results from sustained exposure to high sound levels (>80–85 dB(A)), causing progressive, permanent, and irreversible destruction of cochlear hair cells. Under Control of Noise at Work Regulations (UK/Gulf equivalent): lower action value 80 dB(A) triggers information/training; upper action value 85 dB(A) requires engineering controls and hearing protection.

Question 2

What are the main effects of whole-body vibration (WBV) on workers?

Accepted Answer

Lower back pain, spinal damage, and musculoskeletal disorders — common in workers operating heavy vehicles and plant

Answer

WBV from driving heavy vehicles, construction plant, and industrial machinery transmits energy through the seat and body to the spine. Chronic exposure causes lower back pain, intervertebral disc degeneration, and increased risk of musculoskeletal disorders. Exposure action value is 0.5 m/s² (8-hour average) under EU/UK regulations.

Question 3

What is hand-arm vibration syndrome (HAVS)?

Accepted Answer

A permanent, irreversible condition from prolonged use of vibrating hand tools, causing vascular damage (vibration white finger), sensory loss, and musculoskeletal injury

Answer

HAVS results from chronic exposure to vibrating hand tools (grinders, drills, jackhammers, chippers). Vascular component (vibration white finger): blanching of fingers in cold. Neurological: tingling, numbness, reduced grip. Musculoskeletal: damage to joints. HAVS is progressive, permanent, and disabling.

Question 4

What is the correct approach for managing workers in extreme heat environments in the Gulf?

Accepted Answer

Engineering controls (cooling, shade), acclimatisation programs, hydration, scheduling work to avoid peak heat, heat illness recognition training, and pre-employment health screening

Answer

Gulf construction workers face extreme heat stress risk. Management requires: engineering controls (shade, cooling), acclimatisation (gradual heat exposure over 7–14 days for new/returning workers), scheduled hydration (200–250 mL water every 15–20 min), work-rest ratios, heat illness recognition, and the UAE's mandated outdoor work ban.

Question 5

What is 'sick building syndrome' (SBS)?

Accepted Answer

A collection of non-specific symptoms (headaches, eye irritation, fatigue, respiratory symptoms) experienced by occupants of a specific building, relieved when leaving, without identifiable cause

Answer

SBS is characterized by occupants experiencing symptoms (headaches, fatigue, dry eyes, nasal irritation) that improve on leaving the building. Contributing factors include poor ventilation (inadequate fresh air), chemical off-gassing from furnishings, biological contamination (mold, Legionella risk), and poor temperature/humidity control.

NEBOSH IGC Practice Test

NEBOSH IGC Practice Test

NEBOSH Workplace Hazards 2