Concrete Pour SWMS: Pump, Boom, Vibrator, Cure

The pressure gauge climbs and the line stops moving. The pour has forty minutes before the slab starts to set. Somebody walks to the coupling nearest the blockage and reaches for the clamp. A concrete pour SWMS should have stopped that hand before it moved. Instead, most of them describe the mix, the vibrator and the curing compound, and never mention the pump at all.

Line blockages, uncontrolled pressure release and hose whip sit behind most serious concrete pumping injuries in Australia. Boom contact with overhead powerlines and pump trucks tipping on soft ground sit close behind. None of those hazards live in the concrete. They live in the plant and the pipeline that deliver it, so the SWMS has to name them.

This post walks through the WHS Regulations that apply to a pour. It then sets out the four control points the concrete pour SWMS must state in plain numbers, and the free pre-pour checklist that turns those controls into a gate nobody can skip.

What the WHS Regulations require for a concrete pour SWMS

Under Regulation 291 of the model Work Health and Safety Regulations, a concrete pour is almost always high risk construction work. Regulation 291(o) captures work in an area where powered mobile plant moves. That covers the pump truck and the agitators. Regulation 291(a) applies where the pour sits more than two metres above the ground, for example on a suspended slab. Where precast panels sit in the same package, Regulation 291(m) applies as well. Regulation 291(k) joins the list where the boom works near energised electrical services.

Once any of those paragraphs applies, Regulation 299 requires a SWMS before the work starts. Regulation 300 then requires the crew to carry out the work in accordance with it. The SWMS must identify the high risk construction work, specify the hazards and describe the controls. It must also describe how the crew will implement, monitor and review those controls.

The plant duties sit underneath the SWMS. Regulation 214 requires the person with management or control of powered mobile plant to manage four risks. They are the plant overturning, things falling on the operator, the operator being ejected, and the plant colliding with any person or thing. Next, Regulation 215 adds the operator protective devices, the warning device and the rule against riders. Under Regulation 213, a competent person must maintain and inspect the plant. Concrete placing booms are also item-registered plant under Schedule 5, so the registration must exist before the boom unfolds.

Then comes the licence. Regulation 81 and Schedule 3 make the concrete placing boom its own high risk work licence class at item 22, class PB. Where the truck also carries a vehicle loading crane of ten metre tonnes or more, item 13 adds the CV class.

Why the concrete pour SWMS describes the mix and misses the pump

The pour is usually the concreter’s SWMS, and the concreter does not own the pump. The pump arrives as a subcontractor with its own operator, its own plant and often its own generic document. So the concreter’s SWMS describes the work the concreter controls: placing, screeding, vibrating and curing. The pump gets a single line, if it gets one at all.

Meanwhile, the pump contractor’s document describes the pump in isolation. It rarely knows where the overhead lines are on this site. It does not know what the ground under the pad was last month, or that a two metre basement excavation sits three metres from the outrigger. Two competent documents therefore pass each other, and the interface between them is exactly where the injuries happen.

The fix is not a third document. The fix is one concrete pour SWMS that names the pump set-up, the no-go zone, the blockage rule and the wash-out as controls, with a named owner for each. Both contractors then sign a pre-pour check before the first agitator backs in.

Set-up: ground, outriggers and the hole next door

A mobile placing boom can put twenty-five tonnes or more through a single outrigger foot. The ground has to carry it, and the SWMS has to say how the crew will know. The Safe Work Australia guide to managing risk in construction for concrete pumping gives the numbers. Compacted sand, stiff dry clay and asphalt carry about twenty tonnes per square metre. Loose sand and soft clay carry about ten. Wet clay carries less than ten. Backfilled ground carries whatever the worst layer underneath will hold.

Consequently, the concrete pour SWMS should state the pad size for the ground on this site. Divide the maximum outrigger force in the manufacturer’s manual by the permissible ground pressure and you have the minimum pad area. Timbers should be at least 200 millimetres wide and 75 millimetres thick. Lay them together with no gaps, and set them level on cut ground rather than on a slope. Where an excavation sits nearby, the one-to-one rule applies in compact ground and the two-to-one rule in loose or backfilled ground. For example, a three metre deep trench in backfill needs the closest edge of the pad at least six metres away.

Next, the set-up itself becomes a procedure. Lower each outrigger one at a time and put the full weight of the truck on it. If the pad sinks, retract and increase the pad. Slew the unfolded boom slowly over each outrigger to test it before the pour starts. Short legging is only permitted where the manufacturer’s manual allows it, with a documented working zone and a slew limiter or a marked exclusion. Half a page covers all of that, and none of it appears in a document that only describes the concrete.

Overhead powerlines and the no-go zone

Regulation 166 requires the person conducting the business or undertaking to keep every person, plant and thing at the workplace outside an unsafe distance of an overhead electric line, so far as is reasonably practicable. Queensland runs the same duty through its Electrical Safety Regulation, and every jurisdiction publishes exclusion zones for operating plant. A placing boom is the worst possible plant to run near those zones. It is long, it bounces with every stroke of the pump, and it sways in wind. A spotter on the ground cannot judge its clearance from a line thirty metres up.

For that reason, the first control in the SWMS is elimination. De-energise or re-route the line through the electricity entity, and get that confirmation in writing before the truck arrives. Where elimination is not reasonably practicable, the SWMS names the exclusion zone distance for the voltage in that jurisdiction. It marks the boom’s permitted working arc on the set-up sketch. It nominates a dedicated spotter who does nothing else, and it states the stop rule if the boom approaches the zone. In short, the no-go zone is a line on a drawing and a person with a radio, not a sentence that says take care near power.

The line blockage rule in a concrete pour SWMS

This is the control that most documents never write down, and it is the one that kills. Concrete pumps generate very high line pressures. When a blockage forms, usually at the reducer or in a rubber hose, the pressure builds behind it. If anyone opens a coupling while that pressure is still in the line, the concrete and the fitting leave at speed and the hose whips.

Therefore, the concrete pour SWMS states the blockage rule in plain words. Nobody breaks a line under pressure. Only the pump operator decides the line is blocked, using the pressure gauge. The operator reverses the pump to draw the pressure off before anyone approaches a coupling. A few reverse and forward cycles will often shift a minor jam first. Before any coupling opens, the operator confirms the line holds no pressure, and everyone except the clearing crew leaves the pipeline area. The crew then opens the coupling nearest the pump side of the blockage with their bodies clear of the opening. Where the crew blows the line out with compressed air, they secure the delivery end, double the exclusion zone, and remove the flexible rubber hose first.

Additionally, the SWMS should list the prevention controls the Safe Work Australia guide describes. Use a pumpable mix the engineer has approved. Keep the line diameter at least three to four times the maximum aggregate size. Prime the line properly, minimise bends, avoid abrupt reducers, and fit clamps rated above the maximum line pressure. Retire worn twin-wall pipe before the inner wall goes. Prevention lives in the mix design and the pipeline layout, and both belong in the document.

Hose whip and exclusion zones in the concrete pour SWMS

Hose whip happens whenever air enters the line. It turns most violent when someone removes a coupling on a flexible hose while the line still holds pressure. The delivery hose on the end of the boom should hang freely, with no more than three to four metres of 125 millimetre hose or whatever the manufacturer allows. The end hose never carries metal fittings, and nobody stretches it to reach a corner the boom cannot.

As a result, the concrete pour SWMS draws the exclusion zones for real people. Only the line hand works inside the delivery hose area, and only while the hose is steady. Everyone else stays outside a marked zone while the pump primes, while the crew clears a blockage, and while the crew cleans the line. The boom never swings hoses over workers on the deck. Where the operator cannot see the delivery end, the SWMS nominates a boom spotter, separate from the powerline spotter. Those two roles never collapse into one person doing three jobs.

Wet concrete, silica and the wash-out

Wet concrete is a hazardous chemical. It is alkaline enough to burn skin through a saturated boot in an afternoon, and repeated contact drives dermatitis. Regulation 351 requires the PCBU to manage the risks of using and handling it. Regulation 344 requires the safety data sheet to be available, and Regulation 346 puts it on the hazardous chemicals register. The SWMS names the controls: gauntlet gloves, gumboots with the trousers over the top, eye protection at the hopper and the hose, and an eyewash and clean water at the pour.

Later, the slab gets cut, cored and ground. Regulation 49 sets the workplace exposure standard for respirable crystalline silica at 0.05 milligrams per cubic metre as an eight-hour time-weighted average. From 1 December 2026, the exposure standards list becomes the workplace exposure limits list. Any dry cutting, grinding or scabbling of the cured slab therefore needs water suppression or on-tool extraction and a fit-tested respirator. Write those silica controls into the same SWMS or the one that follows it. Do not leave them to whoever turns up with a demolition saw next week.

Finally, the wash-out. The SWMS names the wash-out location and the bunding that keeps slurry out of the stormwater system. It also states that the boom folds away from the pour, on stable ground, before the crew cleans the line. Pump trucks have tipped during clean-out on short-legged outriggers after a pour, because the crew relaxed once the concrete was down.

Licences, registration and inspection for the placing boom

The pre-pour check confirms four pieces of paper before the boom unfolds. First, the operator holds a current PB high risk work licence. Second, the boom carries its plant item registration under Schedule 5. Third, its periodic inspection is current under AS 2550.15:2019. That standard sets intervals by age: every 1,000 operating hours up to five years old, every 500 hours from five to ten years, and every 250 hours beyond ten years, and at least annually in every case. Where the boom now sits on a different carrier, a recorded stability test exists for that combination.

Equally, the pipeline has its own evidence. Every clamp carries a pressure rating above the pump’s maximum. A competent person has inspected the hoses and end fittings before use. On a vertical or overhead run, the pipeline anchor brackets sit no more than three metres apart unless a competent person says otherwise. The SWMS does not need to reproduce the inspection reports. It needs to say who checks them and when.

Practical Application

Consider a suspended slab pour on a four-storey residential build. The pump contractor arrives at 5:30 am with a 36 metre boom. The only set-up position is the laneway beside a two metre deep services trench that the civil crew backfilled last week. An 11 kilovolt line runs along the street frontage. The pour is 140 cubic metres, with eighteen agitators over the morning.

The concrete pour SWMS for this job carries a set-up sketch. It marks the backfilled trench, applies the two-to-one rule, and places the near-side outriggers at least four metres from the trench edge on 1.2 metre square steel plates over timbers. It records the electricity entity’s written confirmation that the street line stays live. The boom’s permitted arc stays outside the exclusion zone on the same sketch, and S. Wilson is named as the powerline spotter with a radio and a stop word. J. Smith is the pump operator, licence class PB, and A. Jones is the line hand.

Then it states the blockage rule in the operator’s words. J. Smith reads the gauge, reverses the pump, and confirms the line holds no pressure before anyone approaches. A. Jones opens no coupling without that call. The formwork engineer’s pour sequence sits in the appendix, with the maximum pour rate the props can carry. The wash-out bay sits at the rear of the site inside a bunded pit. At 5:45 am, J. Smith, A. Jones and the site supervisor C. Brown walk the checklist together. The gate reads CLEARED before the first agitator reverses in. The whole exercise takes fifteen minutes, and the document now describes the job that is actually about to happen.

Conclusion

A concrete pour SWMS that describes the mix and misses the pump has skipped the hazards that put people in hospital. The Regulations reach every part of the pour. Regulation 291 makes it high risk construction work, Regulations 299 and 300 require the SWMS and compliance with it, Regulations 213 to 215 govern the pump, Regulation 166 governs the powerlines, and Regulations 49, 344, 346 and 351 govern the concrete itself. Four control points carry most of the weight. They are the set-up on assessed ground, the no-go zone with a dedicated spotter, the blockage rule that nobody breaks a line under pressure, and the wash-out and silica controls after the pour. Write those in plain numbers and the document starts protecting people instead of describing concrete.

MiSAFE SWMS builds those controls into the document from the first prompt. The AI drafts the pour SWMS around the plant, the site and the crew you describe, and you keep control of every field. Workers then sign on site by scanning the QR code on the document, so the supervisor sees live who has read the blockage rule before the pump primes.

Ready to act? Contact us today or book a free 45-minute consultation.

Download the Free Template

Download the free Concrete Pour and Placing Boom Pre-Pour Checklist (.xlsx) and put a signed gate between the pump set-up and the first cubic metre of concrete.