Solar Panel Cleaning (Residential & Utility) SWMS

Solar panel cleaning across residential rooftops, pole-mounted arrays and utility-scale solar farms exposes workers to a convergence of fall-from-height, live DC electrical and slip hazards that few other cleaning tasks combine. Even when an inverter is isolated, photovoltaic strings remain energised whenever daylight strikes the modules, producing DC voltages frequently exceeding 600V with no zero-cross to assist arc extinction. Under WHS Regulation 2011 r291 (and equivalent state provisions under the harmonised WHS Regulation 2025 framework), work at heights above 2 metres and work on or near energised electrical installations are classified as High Risk Construction Work, mandating a Safe Work Method Statement before any work commences. Roof traversal on fragile or low-friction surfaces, water-and-electricity interaction, and remote utility-scale environments with delayed emergency response all elevate residual risk. A documented, signed SWMS is the PCBU's primary evidence of consultation, hazard identification and control selection, and must be available on site for the duration of the works.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

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

1. 1Elimination — Where panels are accessible from ground using water-fed telescopic poles, eliminate roof access entirely and clean from a stable ground position.
2. 2Elimination — Schedule cleaning for early morning when panel surface temperatures are below 35°C and irradiance reduces DC string voltage exposure.
3. 3Substitution — Replace conductive aluminium water-fed poles with non-conductive carbon-fibre or fibreglass poles rated and tested to AS/NZS 4267 for live-line work proximity.
4. 4Substitution — Use deionised water cleaning systems instead of detergent solutions to remove conductive contaminants and reduce residual electrical bridging risk.
5. 5Engineering — Install permanent roof anchor points certified to AS/NZS 5532 on residential properties with recurring service contracts, with annual recertification records held.
6. 6Engineering — Deploy temporary edge protection or mobile elevating work platforms (EWPs) on utility-scale sites where ground-level pole reach is insufficient.
7. 7Administrative — Conduct documented pre-start visual inspection of every module, cable and MC4 connector for damage; tag-out and report any compromised string before cleaning commences.
8. 8Administrative — Maintain a two-worker minimum with a dedicated spotter during all roof-based cleaning, with documented rescue plan and trained rescuer within 15 minutes per WHS Reg r80.
9. 9PPE — Class 0 electrical insulating gloves (1000V rated) tested to AS/NZS 2225 worn during any direct module contact, with daily inflation and visual integrity check.
10. 10PPE — Full-body harness compliant with AS/NZS 1891.1 connected to certified anchor with energy-absorbing lanyard, plus non-slip Type II safety footwear with heat-resistant sole.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

On a Tuesday morning at a 4.2MW regional utility solar farm, a two-person crew from a solar O&M contractor arrives for a scheduled bi-annual clean of rows 14 through 28. Before any work begins, the lead technician opens the Solar Panel Cleaning SWMS on a site tablet at the laydown area and walks the offsider through it as the formal pre-start brief. They confirm the array is energised (daylight present), tick the DC electrical hazard and select the carbon-fibre water-fed pole control with deionised water rather than the originally planned roof-traversal method, because morning dew has made the module surfaces slick. The SWMS rescue plan section prompts them to confirm the location of the nearest defibrillator at the inverter station and to log the site manager's mobile as the 15-minute rescuer contact. Both workers sign the sign-on register inside the document, including the offsider who is new to PV work. Midway through row 19 they discover a module with a cracked backsheet and exposed conductor — the SWMS escalation procedure directs them to stop work on that string, photograph the defect, isolate the affected combiner box and notify the asset owner before resuming on row 20. The amended hazard is annotated on the live SWMS and re-signed, demonstrating the dynamic consultation duty under WHS Reg r39.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• AS/NZS 3000 — Electrical installations

Frequently asked questions