Concrete Wire Sawing SWMS
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Diamond wire sawing is high risk construction work in New South Wales for the same reason the wire saw was hired in the first place. Nobody brings a wire saw to a slab on grade. The machine is selected precisely because the element exceeds the depth a road saw or ring saw can reach — bridge decks, piers, columns, transfer beams, thick walls, foundations. Those elements are structural by definition, so the cut removes a load-bearing element, and the load it carried has to go somewhere the instant the wire passes through. Section 291 of the Work Health and Safety Regulation 2025 (NSW) captures the work under the load-bearing demolition category and the temporary support category, and a safe work method statement is required under section 299. SafeWork NSW is the regulator.
Two mechanisms dominate the fatality record and neither is obvious to a bystander. A diamond wire under working tension stores substantial energy along its whole length, and when it parts it whips along the wire path with no reaction time — which means the exclusion zone is the wire path and its plane, not a radius around the machine. The second is a post-tensioned tendon. Cutting into a PT deck or beam without knowing where the tendons run releases the stored energy in a stressed strand instantly and along the tendon axis. It is an anchor ejection inside the element the crew is standing beside. This SWMS is authored around both: scanning before cutting, an engineer's assessment of the load path before set-up, and rigging the section before the final pass rather than after it.
Hazards identified
14 hazards covered, sorted by priority.
Fatality — a parting wire whips along its path at lethal speed with no reaction time
Fatality — a stressed strand releases along the tendon axis beside the crew
Multiple fatalities — the element and everything it carries comes down
Fatality — the cut section drops, rotates or slides the instant the wire passes through
Fatality — struck by the section, a pulley or an anchor released under load
Fatality — electrocution, explosion or release from a service inside the element
Fatality — fall to a lower level, or through the void the cut has just created
Fatality or serious injury to persons below from falling material and slurry
Fatality — electrocution in a continuously wet, slurry-covered work area
Serious injury — high-pressure injection requiring urgent surgical intervention
Fatality — crush injury from the suspended section or contact with the crane
Permanent noise-induced hearing loss from full-shift exposure in a reflective environment
Chemical burns from alkaline slurry, and slips on a continuously wet surface
Musculoskeletal injury from handling the drive unit, pulleys and rigging
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Exclude every person from the wire path and its plane whenever the wire is under tension — the exclusion is the geometry of the wire and its whip envelope, not a radius around the drive unit, and it extends past the pulleys on both sides.
- 2Require the structural engineer to establish whether the element is post-tensioned, prestressed or conventionally reinforced before any core hole or cut is planned, and treat any element whose construction cannot be established as post-tensioned until proven otherwise.
- 3Scan the full cut line and every core hole location by GPR or equivalent by a competent person, mark tendons and services physically on the element, and set the cut line clear of them — a drawing is an indication, not a location.
- 4Obtain an engineering assessment of structural stability at every stage of the cut before set-up, and install and verify temporary support as carrying the load before the wire passes through.
- 5Rig and support the cut section before the cut is completed, so that when the wire parts the concrete nothing moves — the section is already held.
- 6Design lifting points into the section by the engineer rather than improvising them, and take the weight on the crane before the final pass.
- 7Anchor pulleys and the drive unit to the manufacturer's specification into verified concrete, and refer any spalled, cracked or unverified fixing location to the engineer rather than fitting a longer bolt.
- 8Have the asset owner isolate and prove de-energised any embedded or adjacent service that cannot be cleared by scanning, and relocate the cut line where clearance cannot be achieved.
- 9Plan and install edge protection to the opening the cut will create as part of the cut sequence rather than afterwards, and barricade the opening the instant the section lifts.
- 10Exclude persons from beneath the cut for its full depth and the section's travel path, and provide catch platforms or covered walkways where access below is unavoidable.
- 11Provide RCD protection on every circuit, suspend leads clear of slurry, and plan the slurry path before set-up because it goes where gravity sends it.
- 12Depressurise and isolate hydraulics before touching any hose or fitting, and locate leaks with cardboard rather than a hand.
- 13Bund and vacuum-recover slurry at the cut as it is generated, and provide washing facilities and eyewash at the work area.
- 14Retire the wire at the manufacturer's wear limit rather than running it out, inspect for bead loss, kinking and splice condition before every cut, and stop on any change in note, vibration or tension.
Applicable Codes of Practice
The benchmark for structural stability, engineering assessment, exclusion zones and the removal of load-bearing elements, including the identification of post-tensioned and prestressed elements before any cutting.
The benchmark for construction-phase risk management, exclusion zones and coordination with other trades and with occupants of the structure being cut.
The benchmark for noise exposure assessment and control, and for audiometric testing where the exposure standard is exceeded — relevant because a concrete structure reflects noise back at the operator.
The requirement for an engineering assessment of structural stability at every stage where a load-bearing element is removed, and the sequencing and support of partial demolition.
The basis on which the structural engineer assesses the element, the load path after the cut, and the treatment of post-tensioned and prestressed members.
The rating, inspection and use of the lifting gear that supports the section before the cut and removes it afterwards.
High-Risk Construction Work triggered
Wire sawing is routinely carried out on bridge decks, at slab edges and over voids, and the cut itself creates a new unprotected edge the moment the section is removed.
The wire saw is selected because the element exceeds the depth a road saw can reach — bridge decks, piers, columns, transfer beams. Those elements are load-bearing by definition, so the cut is the removal of a load-bearing element and the load it carried must be transferred before the wire passes through.
Removing a structural element requires the load path to be resolved and temporary support installed and verified as carrying the load before the cut is completed. The cut is a structural modification, not a cutting job.
Services are routinely embedded in or adjacent to the elements wire sawing is used on, and a wire cut passes through the full thickness. The saw's own supply also runs in slurry.
A crane or lifting device removes the cut section, and the section's mass makes hand-guiding impossible.
Carrying out high risk construction work without a compliant SWMS is an offence under the Work Health and Safety Regulation 2025 (NSW). Beyond the penalty, a structural collapse or a post-tensioned tendon release during cutting attracts immediate SafeWork NSW attention, and the SWMS is the first document requested. Where the SWMS does not record the engineering assessment, the scanning regime and the exclusion geometry, the PCBU has no evidence the risk was managed.
Who this is for
- →Concrete cutting and sawing contractors carrying out wire sawing on structural elements
- →Demolition contractors removing load-bearing elements from bridges, piers, columns and transfer structures
- →Civil and infrastructure contractors cutting bridge decks, marine structures and foundations
- →Principal contractors required to obtain and review a SWMS before wire sawing starts on site
- →Structural remediation contractors opening penetrations through thick or post-tensioned elements
What you receive
- ✓A complete, editable Safe Work Method Statement authored for New South Wales — the WHS Act 2011 (NSW), the WHS Regulation 2025 (NSW), and SafeWork NSW as regulator, with correct section numbers throughout
- ✓14 identified hazards with initial and residual risk ratings on a 5x5 matrix, each with the full hierarchy of control from elimination through to PPE
- ✓The wire-plane exclusion control set — the geometry of the whip envelope rather than a radius around the machine, extending past the pulleys on both sides
- ✓The post-tensioned tendon control set — scanning before cutting, physical marking, the tendon-axis exclusion, and the rule that a drawing is an indication and not a location
- ✓The structural stability control set requiring the engineer's assessment and verified temporary support before the wire passes through
- ✓The controlled-release control set — rigging and supporting the section before the final pass, with engineer-designed lifting points
- ✓The full high risk construction work breakdown — load-bearing demolition, temporary support, energised electrical, powered mobile plant and falls — with the reason each category applies
- ✓A PPE matrix mapping each task to the required equipment and Australian Standard, including the explicit statement that PPE does not stop a parting wire
- ✓Microsoft Word (.docx) format, unbranded, editable fields for PCBU, ABN, site, dates and worker sign-on
Worked example
A contractor is engaged to remove a 900 mm deep section of a bridge deck to form a new services penetration. The deck is thirty years old and the as-built drawings show conventional reinforcement. The crew sets out from the drawings, core drills the corner entry holes, and on the second hole the drill binds and then releases with a sharp report. A strand has been cut. The deck was post-tensioned during a strengthening programme that was never marked up on the as-builts. The controls in this SWMS break that chain at three points. The structural engineer's assessment is required before the cut is planned, and an element whose construction cannot be established from the record is treated as post-tensioned until proven otherwise — which this deck's incomplete as-builts would have triggered. Scanning by GPR is required on the full cut line and at every core hole location, not just where the drawings suggest something is present, with tendons marked physically on the concrete. And the cut line is set clear of the marked tendons, or a de-stressing method is specified in writing by the engineer where a strand must be cut. The outcome under the SWMS is a delay of half a day for scanning and an engineer's review. The outcome without it is a stressed strand releasing along its axis beside a crew who had no reason to expect it, from an element the paperwork said was conventionally reinforced.
Related legislation
- Work Health and Safety Act 2011 (NSW) — Section 19 primary duty of care, extending to persons below the cut and to occupants of the structure; Section 47 consultation; Sections 35–38 notifiable incidents
- Work Health and Safety Regulation 2025 (NSW) — Section 291 high risk construction work; Section 299 SWMS required and content prescribed; Section 302 review
- Work Health and Safety Regulation 2025 (NSW) — Chapter 5, plant: guarding, isolation and lock-out for wire threading and maintenance, and the duty to use plant within its design limits
- Work Health and Safety Regulation 2025 (NSW) — Part 4.7 Division 4, sections 154 and 157: the prohibition on energised electrical work, relevant to embedded conduit and to the saw's own supply running in slurry
- Work Health and Safety Regulation 2025 (NSW) — Chapter 4 Part 4.1: the duty to manage risks from noise, and Part 4.4: the duty to manage the risk of falls
Frequently asked questions
Is wire sawing always high risk construction work?
In practice, yes — and for a structural reason rather than a formal one. A wire saw is selected because the element is too deep for a road saw or ring saw, and elements of that depth are load-bearing. That engages the load-bearing demolition category at section 291, and usually the temporary support category with it. If the work genuinely does not involve a structural element, the classification should be reconsidered on its facts — but that situation is rare enough that it is not the assumption this SWMS is built on.
Why is the exclusion zone described as a plane rather than a radius?
Because that is how a broken wire behaves. A tensioned diamond wire stores energy along its entire length, and when it parts it whips along the wire path — including past the pulleys at both ends. A circular exclusion drawn around the drive unit leaves people standing directly in the whip envelope while feeling safely distant. The exclusion has to follow the geometry of the wire itself.
We have as-built drawings. Do we still need to scan?
Yes. The SWMS treats a drawing as an indication and not a location. Strengthening works, post-tensioning added during a later programme, and services installed after handover routinely fail to reach the as-builts. Where the record cannot establish that an element is conventionally reinforced, this SWMS requires it to be treated as post-tensioned until scanning proves otherwise.
Does this SWMS cover the removal of the cut section?
Yes. Rigging, supporting and removing the section is treated as part of the cut rather than as a separate lift, because the critical moment is the last pass of the wire — the section must already be held before the concrete parts. Engineer-designed lifting points, rated gear to AS 4991, licensed dogging and the exclusion beneath the section are all in scope.