Silica Dust Monitoring in ConstructionSydney & Greater Sydney

Concrete typically contains 10-25% crystalline silica by weight. Dry cutting with diamond blades, angle grinders, and concrete saws generates high concentrations of respirable quartz dust. The new NSW Chapter 8A regulations classify concrete cutting, sawing, grinding, and drilling as high-risk crystalline silica processes requiring a Silica Risk Control Plan, air monitoring, health monitoring, and worker registration on the NSW Silica Worker Register.

Engineered stone contains more than 90% crystalline silica. NSW and other states have banned the manufacture, supply, and installation of unfinished engineered stone products. However, legacy engineered stone removal during kitchen and bathroom renovations is permitted under controlled conditions. Air monitoring during legacy removal confirms that control measures are effective.

Building demolition disturbs concrete, brick, and mortar, generating RCS alongside asbestos fibres. Excavation through sandstone (common in Sydney geology) produces additional silica exposure. Co-monitoring for RCS and asbestos is often required on demolition sites.

Sydney has multiple major tunnel projects generating sustained RCS exposure for tunnel workers. Tunnel boring machines (TBMs), road headers, and drill-and-blast operations in sandstone geology produce respirable quartz. Underground ventilation effectiveness and diesel particulate co-exposure are additional monitoring considerations.

Typical Worker Groups

Common similar exposure groups (SEGs) assessed for this sub-category.

Regulatory Context

NSW WHS Regulation 2025 Chapter 8A (effective 1 September 2024) requires a Silica Risk Control Plan for any high-risk crystalline silica process. From 1 October 2025, workers performing high-risk silica work must be registered on the NSW Silica Worker Register within 28 days. Health monitoring (spirometry and chest X-ray) is mandatory for workers with significant RCS exposure. SafeWork NSW actively enforces with stop-work prohibition notices and on-the-spot fines up to $3,600. The WES transitions to a Workplace Exposure Limit (WEL) from 1 December 2026.