NEBOSH CC Dust & Noise in Construction

Question 1

Which disease is caused by the inhalation of respirable crystalline silica (RCS) dust on construction sites?

Accepted Answer

Silicosis

Answer

Silicosis is a fatal, irreversible lung disease caused by breathing in fine respirable crystalline silica (RCS) dust from materials such as concrete, mortar, sandstone and granite. It causes progressive scarring of the lung tissue.

Question 2

Which construction activities commonly generate respirable crystalline silica dust?

Accepted Answer

Cutting, grinding, drilling and chasing concrete, brick, stone and mortar

Answer

Cutting, grinding, drilling and chasing operations on silica-containing materials such as concrete, brick, stone and mortar produce very high concentrations of RCS dust. Dry cutting is particularly hazardous and should be avoided.

Question 3

What is the Workplace Exposure Limit (WEL) for respirable crystalline silica dust under EH40?

Accepted Answer

0.1 mg/m³ (8-hour TWA)

Answer

The WEL for respirable crystalline silica is 0.1 mg/m³ as an 8-hour time-weighted average (TWA). This is a very low concentration, reflecting the significant hazard posed by even small amounts of RCS dust.

Question 4

What is the most effective engineering control for reducing dust during dry cutting operations on a construction site?

Accepted Answer

On-tool dust extraction combined with water suppression (wet cutting)

Answer

On-tool dust extraction captures dust at the point of generation before it becomes airborne. Combined with wet cutting (which uses water to suppress dust), this provides the most effective engineering control. RPE should also be worn as a supplementary measure.

Question 5

Which regulations govern occupational exposure to hazardous substances including dust on construction sites?

Accepted Answer

Control of Substances Hazardous to Health Regulations 2002 (COSHH)

Answer

COSHH 2002 requires employers to assess, prevent or control exposure to substances hazardous to health, including dusts such as RCS, wood dust and asbestos. The regulations require a COSHH assessment for all hazardous substances.

NEBOSH Construction Certificate Practice Test

NEBOSH Construction Certificate Practice Test

NEBOSH CC Dust & Noise in Construction