Slab on Ground Construction SWMS

Slab on ground construction involves excavation and levelling of the building footprint, placement of vapour barriers and mesh reinforcement, formwork setup, and the pour, screed, float and finish of large volumes of ready-mix concrete. The work concentrates multiple high-energy hazards into a single work zone: concrete trucks and line pumps manoeuvring near workers, boom or trailer pump lines under pressure, wet concrete causing severe alkali burns and dermatitis, and repetitive stooped screeding and power-trowelling that drives musculoskeletal injury. Silica exposure arises when cutting control joints in cured slabs.

Under the Work Health and Safety Regulation 2025 (NSW), slab work involving powered mobile plant is high risk construction work under section 291(o), and a Safe Work Method Statement must be prepared before work commences under section 299. Controls follow the hierarchy in section 36 — eliminate reversing movements through exclusion zones and spotters, engineer against pump line whip and slip hazards, and only then rely on administrative measures and PPE.

Hazards identified

12 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Eliminate reversing where possible by designing one-way truck movements and drive-through pour sequences; where a concrete pump can place the pour from a single set-up, prefer this over truck-discharge to reduce plant movement in the work area.
2. 2Substitute dry-cutting of control joints with wet-cut diamond sawing using an integrated water feed to suppress respirable crystalline silica below the workplace exposure standard of 0.05 mg/m³ (8-hour TWA).
3. 3Establish a documented exclusion zone around powered mobile plant with physical barriers and a dedicated trained spotter in high-visibility clothing maintaining eye contact with the operator; comply with AS 2550.1 (Cranes, hoists and winches — Safe use) principles for exclusion and AS 1742.3 for any traffic control on public frontage.
4. 4Set up concrete placing equipment in accordance with AS 2550.15 (Cranes — Concrete placing equipment); inspect delivery lines, clamps and safety pins before each pour, secure the end hose, and never attempt to clear a blockage under pressure — depressurise per manufacturer procedure.
5. 5Locate and prove underground services before excavation using Before You Dig Australia (BYDA / Dial Before You Dig) plans, cable locators and hand-dig / vacuum excavation within 500 mm of identified assets, consistent with AS/NZS 4853 principles for electrical safety.
6. 6Cap or bend over all vertical starter bars and protruding reinforcement with proprietary impalement caps rated for fall protection; do not use plastic mushroom caps as fall protection.
7. 7Provide RCD-protected 240V supply, inspect and tag leads and power tools in accordance with AS/NZS 3012 (Electrical installations — Construction and demolition sites); elevate leads clear of wet slab surfaces.
8. 8Rotate finishing crews, provide screed handles at working height, use mechanical mesh-lifting and roll-out reinforcement to reduce manual handling risk consistent with the Code of Practice: Hazardous manual tasks.
9. 9Implement a heat management plan for pours forecast above 30 °C — early starts, shaded rest areas, electrolyte hydration, and rescheduling of large pours; provide SPF 50+ sunscreen, wide-brim hard hats and long sleeves.
10. 10Mandatory PPE: alkali-resistant nitrile or PVC gauntlets, waterproof gumboots (not leather), safety glasses to AS/NZS 1337.1, P2 respirators to AS/NZS 1716 when cutting or grinding, and hearing protection to AS/NZS 1270 during power-trowel and saw operations; emergency eyewash and clean water for skin flushing available at the pour.
11. 11Provide site-specific induction covering pump layout, spotter signals and emergency stop; conduct a documented pre-pour toolbox talk with the pump operator, concrete supplier and finishing crew.
12. 12All workers to hold a current General Construction Induction (White Card, CPCCWHS1001); the SWMS is developed in consultation with workers under section 47 of the WHS Act 2011 (NSW) and reviewed under section 302 of the WHS Regulation 2025 (NSW) if controls fail, an incident occurs or the work method changes.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

A concreting contractor is placing a 220 m² waffle raft slab for a two-storey dwelling in Kellyville in Sydney's north-west. A boom pump is set up on the street verge with the concrete truck reversing into position from Windsor Road. The SWMS identifies section 291(o) as the HRCW trigger, nominates a spotter with a whistle and radio between the pump hopper and the finishing crew, establishes a 3 m exclusion zone around the placing boom, and specifies wet-cut sawing of control joints the following day with an on-tool water feed and P2 respirators. The document is signed by the four-person crew and the pump operator at the pre-pour toolbox and retained on site for the duration of the work.

Related legislation

• Work Health and Safety Act 2011 (NSW) — sections 19, 31, 32, 47
• Work Health and Safety Regulation 2025 (NSW) — sections 291, 299, 302
• Work Health and Safety Regulation 2025 (NSW) — Chapter 7 (Hazardous chemicals) and section 49 (airborne contaminants)
• Work Health and Safety Regulation 2025 (NSW) — Part 4.1 (Noise) and Part 4.2 (Hazardous manual tasks)
• Work Health and Safety Regulation 2025 (NSW) — Part 4.4 (Falls)
• Environmental Planning and Assessment Act 1979 (NSW) — construction site management obligations

Frequently asked questions