Mini / Spider Crane Operations SWMS

Mini and spider crane operations using Maeda, Unic, Jekko and similar tracked compact cranes present distinct risks beyond conventional mobile crane work because they are routinely deployed indoors, on suspended slabs, in atriums, lift shafts, glazed facades and other restricted-access environments where outrigger loadings, overhead obstructions and bystander exposure are tightly constrained. Under WHS Regulation 2025 section 291, any crane lift on a construction site is classified High Risk Construction Work, triggering the mandatory requirement for a Safe Work Method Statement prepared in consultation with workers before work commences. The compact footprint of these cranes often gives a false impression of low risk, yet outrigger point-loads can exceed 4 tonnes per pad on suspended floors, and tipping incidents during indoor glazing and HVAC lifts continue to be reported to regulators. This SWMS addresses CN/CT high risk work licence verification, vacuum lifter integration, ground bearing capacity assessment, and dual-control operation in restricted sightline conditions.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

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

1. 1Elimination — Where feasible, eliminate the lift entirely by specifying pre-installed components, modular delivery sequencing or permanent building maintenance units during design review under Safe Design principles.
2. 2Elimination — Remove all non-essential personnel from the lift exclusion zone established at 1.5 times load radius before slewing or boom extension commences.
3. 3Substitution — Substitute internal combustion spider crane models with battery-electric variants (Maeda MC285, Jekko SPX) for all indoor lifts to eliminate exhaust gas exposure.
4. 4Substitution — Replace manual taglines with rigid push-pull poles where load orientation control is required in confined indoor lifts under 3 metre radius.
5. 5Engineering — Verify suspended slab capacity via structural engineer certificate and deploy steel spreader mats sized to keep outrigger pad pressure below documented allowable bearing load.
6. 6Engineering — Use vacuum lifters certified to AS 4991 with dual-circuit redundancy, audible low-vacuum alarm and secondary mechanical safety strap rated to 2x working load.
7. 7Administrative — Verify CN (non-slewing) or CT (slewing) high risk work licence currency for every operator and dogger CD licence for all riggers before lift commencement.
8. 8Administrative — Conduct documented pre-start lift study including load chart verification, ground assessment, exclusion zone marking and emergency rescue plan signed by competent person.
9. 9PPE — Issue and enforce wear of AS/NZS 1801 hard hats, AS/NZS 1337.1 impact-rated eye protection, AS/NZS 2210.3 safety footwear and high-visibility AS/NZS 4602.1 garments.
10. 10PPE — Provide cut-resistant gloves to AS/NZS 2161.3 Level D for riggers handling wire rope slings, glazing edges and vacuum lifter rubber seal positioning.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

On a 14-storey commercial refurbishment, a glazing subcontractor is scheduled to install 280kg structural glass panels into a level 9 atrium using a Maeda MC305C spider crane and a vacuum lifter. At the 6:30am pre-start, the site supervisor opens this SWMS on a tablet and walks the three-person crew through it line by line. The CT-licensed operator confirms the structural engineer's certificate authorising 3.2 tonne point loads on the level 9 slab and lays out 1200x1200mm steel spreader mats under each outrigger as the SWMS requires. The dogger identifies a previously unnoticed sprinkler main running across the proposed slew path — a hazard the SWMS flags under overhead services contact — and the crew adjusts the crane setup position 1.8 metres south to create clearance, documenting the change on the SWMS variation page. Each worker signs the daily sign-on register acknowledging they have read the controls and hold current CT, CD or general construction induction tickets. During the third lift, the vacuum lifter low-vacuum alarm activates briefly; per the SWMS emergency response section the operator lowers the panel to a stable rest position, the rigger reseats the seal, and a fresh vacuum test is performed before the lift resumes. The SWMS is re-signed after the variation and retained on site for the regulator-mandated two-year period.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• AS 2550 — Cranes, hoists and winches; AS 1418 series

Frequently asked questions