Concrete Works Including Excavation SWMS

Concrete works incorporating excavation combine two of the highest-risk construction activities recognised under the WHS Regulation 2025 — trenching and structural concreting — into a single integrated workflow. Typical tasks include footing and strip trench excavation to depths exceeding 1.5 metres, slab edge and pad preparation, formwork installation against open ground, placement of wet concrete by chute, pump or kibble, and management of spoil stockpiles adjacent to open excavations. Because the work involves both excavation deeper than 1.5 metres and the manual handling of wet concrete, formwork and reinforcement, it triggers two separate categories of High Risk Construction Work under section 291 of the WHS Regulation 2025. A documented, signed and consulted Safe Work Method Statement is mandatory before work commences, must be kept on site for the duration of the works, and must be retained for at least two years after any notifiable incident. The SWMS must address ground collapse, plant interaction, concrete burns, silica exposure from cut substrates, and the underground services identified through the Before You Dig Australia (BYDA) referral process.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

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

1. 1Elimination — Redesign foundations with the engineer to use screw piles or shallow raft slabs where geotechnical conditions permit, removing the need for excavations exceeding 1.5 metres.
2. 2Elimination — Sequence works so concrete placement occurs immediately after excavation inspection, eliminating prolonged open-trench exposure to weather, surcharge loading and unauthorised access overnight.
3. 3Substitution — Specify low-chromate, lower-alkalinity concrete mixes and self-levelling products to reduce skin burn severity and the manual screeding effort required at the placement face.
4. 4Engineering — Install engineer-designed trench shields, hydraulic shoring or battered walls compliant with AS 5047 and the Excavation Work Code of Practice for any excavation deeper than 1.5 metres.
5. 5Engineering — Position spoil stockpiles a minimum of 1 metre from trench edges, install hard barricades to 1.8m clearance, and provide compliant ladder access every 9 metres of trench run.
6. 6Engineering — Use concrete line pumps, kibbles and powered screeds to mechanise placement, and on-tool H-class HEPA dust extraction for any cutting or grinding of cured concrete.
7. 7Administrative — Complete a BYDA referral, on-site service location with cable locator and potholing, and a pre-pour permit signed by the supervisor before any plant or worker enters the excavation zone.
8. 8Administrative — Conduct daily pre-start briefings using this SWMS, document trench inspections after rain or vibration events, and rotate workers through finishing tasks to limit manual handling duration.
9. 9PPE — Issue chemical-resistant gauntlet gloves, alkali-resistant gumboots, sealed safety eyewear, long-sleeve high-visibility clothing and barrier cream for all wet concrete contact tasks.
10. 10PPE — Provide P2 half-face respirators for silica-generating tasks, hard hats with chinstraps for trench work, and ensure emergency eyewash and clean water rinse stations are within 10 metres of the pour.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

On a two-storey townhouse development, the concreting crew is preparing to pour footings into trenches benched to 1.8 metres along the eastern boundary. At the 6:30am pre-start, the leading hand opens this SWMS on a tablet and walks the four-person crew through it tailgate-style. The team confirms the BYDA plans match the potholed Telstra conduit flagged in pink paint two metres from the south-east corner, and that the hydraulic trench shield from the morning's delivery is rated for the loam-over-clay profile noted in the geotech report. Each worker initials the hazard register, paying particular attention to the alkaline burn control requiring full gauntlets and sealed eyewear when the line pump discharges. Mid-pour, the supervisor notices the agitator driver positioning within 800mm of the trench lip — outside the SWMS-mandated 1-metre spoil and plant setback. Work is paused, the truck repositioned, and the change documented as a SWMS amendment on the tablet, re-signed by the crew before placement resumes. After the pour, the SWMS is filed against the lot number and retained for the project compliance pack, ready for production if a WHS inspector attends or a notifiable incident occurs within the retention window.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• AS 3600 — Concrete structures

Frequently asked questions