Standby Power & Generator Connection SWMS

Standby power installation is the licensed work that connects and commissions a generator set, an automatic transfer switch and changeover, and the fuel or gas supply that feeds the set. The dominant hazards are electrocution during connection and commissioning, backfeed or islanding where a generator energises a network believed de-energised, arc flash at the board or transfer switch, fuel fire or gas leak, and carbon monoxide from an engine running in an enclosure. This SWMS covers the generator, transfer switch, fuel or gas connection and commissioning of the standby supply; it does not cover the building's main switchboard upstream, the building's permanent installation, or the design of the standby system, which are documented separately.

Under the model Work Health and Safety Act 2011 and the harmonised Work Health and Safety Regulations adopted in each state and territory, this is high risk construction work because it is carried out on or near energised electrical services and, for a gas-fired set, on or near pressurised gas piping; Victoria operates the equivalent provisions under the Occupational Health and Safety Act 2004 and Occupational Health and Safety Regulations 2017. Generating-set installation follows AS/NZS 3010, the wiring rules follow AS/NZS 3000, safe working on or near low-voltage equipment follows AS/NZS 4836, and a gas-fired set is connected to AS/NZS 5601.1 by a licensed gasfitter. The defining control is a mechanically and electrically interlocked changeover or transfer switch so the generator and mains can never connect at the same time.

Failure to meet the primary duty of care is prosecuted under the Category 1 to 3 offences in the Work Health and Safety Act (and the equivalent provisions in Victoria's Occupational Health and Safety Act 2004), with maximum penalties indexed in most jurisdictions, imprisonment available for individuals, and a separate industrial manslaughter offence; current figures follow the prevailing penalty schedule of the responsible state regulator. This document is structured to satisfy the safe work method statement content requirements of the harmonised regulations and documents a controlled connection and commissioning.

Hazards identified

11 hazards covered, sorted by priority.

Control measures

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

1. 1Elimination: Isolate and prove de-energised before connection, with lock-out and tag-out at the source and a test-for-dead to AS/NZS 4836.
2. 2Elimination: Prevent parallel paths with a mechanically and electrically interlocked changeover or automatic transfer switch so the generator and mains cannot connect simultaneously.
3. 3Elimination: Work de-energised, with correctly rated and enclosed switchgear, an arc-flash assessment and restricted access where energised work is unavoidable.
4. 4Substitution: Use a sealed fuel system over open transfer, bunded diesel storage or a gas line and isolation valve to AS/NZS 5601.1 with leak testing, and the safety data sheet on hand.
5. 5Elimination: Avoid indoor running where possible; otherwise provide a flue to the outside and mechanical ventilation sized for the engine, with a carbon monoxide alarm.
6. 6Engineering: Separate fuel and gas from ignition sources and hot surfaces, use a fire-rated enclosure, keep an extinguisher rated for the fuel on hand, and maintain housekeeping.
7. 7Engineering: Guard and lag hot surfaces, allow cooling before work, and provide signage; wear heat-resistant gloves.
8. 8Elimination: Place the generator and transfer switch by crane or forklift rather than manual lift, with rated lifting gear, a defined landing point, a licensed operator and a dogger.
9. 9Engineering: Use an acoustic canopy and exhaust silencer, limit time near a running set against the 85 dB(A) eight-hour exposure standard to AS/NZS 1269, and provide hearing protection.
10. 10Engineering: Use insulated terminal covers and correct polarity, connect last and disconnect first per procedure, and allow no metal across terminals; wear eye protection.
11. 11Elimination: Pothole located services, hand-dig near located assets, and complete a Before You Dig Australia enquiry before fuel-line or conduit civil works.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

A contractor is installing a standby generator with an automatic transfer switch for a building, connecting the set, the changeover and the fuel supply and commissioning the standby mode. Because the work is carried out on or near energised electrical services, and the set is gas-fired and connected to pressurised gas piping, it is high risk construction work, so the team builds the safe work method statement around de-energised connection, the prevention of backfeed, and the fuel and exhaust hazards. The generator and transfer switch are placed by crane with rated gear, a dogger and a defined landing point rather than manual lift. Every connection is made dead: the supply is isolated, locked, tagged and proven de-energised with a test-for-dead to AS/NZS 4836, and the changeover is a mechanically and electrically interlocked transfer switch so the generator and the mains can never be connected at the same time, removing the backfeed and islanding risk to anyone working on the network. Where energised work cannot be avoided, it is done to an arc-flash assessment with rated, enclosed switchgear and restricted access. The gas connection is made by a licensed gasfitter to AS/NZS 5601.1 with an isolation valve and leak testing, fuel and gas are kept separate from ignition sources and hot surfaces, and an extinguisher rated for the fuel is on hand. The engine is not run indoors where it can be avoided; where it must, a flue to the outside and mechanical ventilation sized for the engine, with a carbon monoxide alarm, control exhaust fumes. Hot surfaces are guarded and allowed to cool, an acoustic canopy and hearing protection manage noise, and any fuel-line civil works follow a Before You Dig Australia enquiry. Workers sign on to the statement before starting, the isolation, interlock-proving and commissioning records are kept, and the signed statement is held on site for the responsible state regulator.

Related legislation

• Work Health and Safety Act 2011 (harmonised; enacted in all states and territories except Victoria, which applies the Occupational Health and Safety Act 2004), s.19 — Primary duty of care to workers and to other persons at or near the workplace
• Harmonised Work Health and Safety Regulations, section 291 — Defines high risk construction work (Victoria: Occupational Health and Safety Regulations 2017, Part 5.1)
• Harmonised Work Health and Safety Regulations, section 299 — Content and review requirements for a safe work method statement for high risk construction work (Victoria: regulation 327; Tasmania: regulation 312)
• Harmonised Work Health and Safety Regulations, Part 4.7 — Electrical safety: the prohibition on energised electrical work except where de-energising is not reasonably practicable and the prescribed conditions are met, with duties for RCD protection and testing (Victoria applies the Occupational Health and Safety Regulations 2017 and state electrical-safety legislation)
• State gas-safety legislation — The gas connection of a gas-fired generating set must be carried out by a licensed gasfitter and pressure and leak tested

Frequently asked questions