Pipeline Pre-Commissioning & Cleaning SWMS
Pipeline pre-commissioning — flooding, cleaning pig runs, dewatering, drying with desiccant or vacuum. Confined-space risk where tie-in points open. Stored-energy from compressed-air drying.
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Pipeline pre-commissioning prepares a newly constructed and tested pipeline for service through a sequence of operations — typically cleaning and gauging, dewatering after hydrostatic testing, drying, and then purging and filling with the product or an inert medium so the line can be brought into operation. The dominant hazards arise during purging and gas-in, when a flammable product is introduced into a line that contains air, creating the potential for a flammable or explosive atmosphere within the pipeline and at vent points, and when nitrogen or other inert media used for purging and drying create an asphyxiation hazard at vents and in any confined space. This document is written on the basis that pre-commissioning follows an engineered sequence in which flammable and air atmospheres are never allowed to form an explosive mixture, and inert and product venting is controlled and monitored.
Pre-commissioning is high risk construction work because it is carried out on or near chemical or fuel lines and in an area that may have a contaminated or flammable atmosphere during purging and gas-in, and because parts of the work may involve entry to a confined space such as a vessel or pit — so a safe work method statement is required before the work commences, kept readily accessible, and given to the principal contractor if one is appointed. Pre-commissioning of high-pressure pipelines is carried out under the AS 2885 suite and the project's commissioning procedures, with purging sequences designed so that air and flammable product do not mix into an explosive atmosphere. This document coordinates the atmospheric, asphyxiation and product-handling controls so the line is brought into service safely.
Hazards identified
9 hazards covered, sorted by priority.
Explosion within the pipeline or at vent points from an air-product mixture
Oxygen displacement and rapid loss of consciousness without warning
Flammable or asphyxiating atmosphere at and around vent points
Oxygen deficiency, contaminated atmosphere and restricted egress in the confined space
Release of pressure from connections or fittings during gas-in
Ignition of vented or leaked flammable product
Acute exposure where the product contains toxic components
Environmental breach where discharge is uncontrolled
Back and crush injury from heavy equipment and connections
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Engineering: design and follow a purging and gas-in sequence to the AS 2885 suite and the commissioning procedure so that air and flammable product are never allowed to mix into an explosive atmosphere — typically by inerting the line before product is introduced.
- 2Engineering: continuous atmospheric monitoring at vents and the work area for flammable gas and oxygen during purging and gas-in, with defined criteria, and oxygen monitoring for asphyxiation where inert media are used.
- 3Engineering: control venting to safe locations away from people and ignition sources, with vent points managed and signed, and exclude ignition sources from the gas-in area.
- 4Engineering: where confined space entry is required for any step, atmospheric testing, forced ventilation, entry permit, standby person and rescue arrangements.
- 5Administrative: a permit-to-work system for the pre-commissioning sequence, exclusion zones around vent and gas-in points, and competency verification for the operators and the permit issuer.
- 6Administrative: prepare a SWMS before the work for the high risk construction work — work on or near chemical or fuel lines, in a potentially flammable atmosphere, and in or near a confined space — and brief the commissioning sequence and emergency response.
- 7PPE: flame-resistant clothing for the gas-in phase, supplied-air respiratory protection for any oxygen-deficient or confined atmosphere, and gas and oxygen detection carried by workers, per AS/NZS 1715 and AS/NZS 1716.
- 8Administrative: all workers must hold a valid White Card (General Construction Induction Training, CPCCWHS1001) before entering any construction workplace, with pipeline and any confined space competencies verified as applicable.
- 9Administrative: conduct a daily pre-start toolbox talk covering the day's work scope, identified hazards, required PPE, emergency procedures, and any changes since the previous shift, and record attendance in the SWMS consultation section.
- 10PPE: eye protection to AS/NZS 1337.1, hearing protection where required, gloves, and Class I or Class II safety footwear with protective toecap to AS/NZS 2210.3.
- 11Administrative: review and update this SWMS whenever the work scope, pipeline conditions or method changes, after any incident or near miss, when a worker or health and safety representative raises a concern, or at minimum every 12 months.
Applicable Codes of Practice
The pipeline standard governing commissioning, purging and gas-in of high-pressure pipelines.
The overarching principles for safe operation within which pre-commissioning is conducted.
Atmospheric testing, ventilation, entry permit and rescue controls for confined space entry during pre-commissioning, including inert-atmosphere asphyxiation.
The risk management process and hierarchy of controls applied to the flammable-atmosphere and asphyxiation hazards of gas-in.
Selection, fit testing, use and maintenance of the respiratory protection required for the atmospheric, fume and product hazards of the work.
High-Risk Construction Work triggered
Introducing product into and commissioning a pipeline carrying gas and liquid petroleum is work on or near chemical or fuel lines, which is high risk construction work requiring a SWMS before the work commences.
Purging and gas-in can create a flammable or contaminated atmosphere in the line and at vent points, bringing the work within this category and driving the atmospheric and ignition controls.
Where pre-commissioning involves entry to a vessel, pit or other confined space, the confined space category and its atmospheric, ventilation and rescue controls apply.
Pipeline pre-commissioning is high risk construction work where it is on or near chemical or fuel lines, in a potentially flammable or contaminated atmosphere during purging and gas-in, or in or near a confined space, so a SWMS must be prepared before the work commences, kept readily accessible, reviewed as necessary, and given to the principal contractor if one is appointed. Pre-commissioning is carried out under the AS 2885 suite and the project commissioning procedures, with purging sequences engineered so that air and flammable product do not mix into an explosive atmosphere, and inert-media asphyxiation and venting controlled and monitored. An explosion or asphyxiation during gas-in can be fatal, and breaches of the primary duty of care under the model WHS Act are actively enforced, with offence categories running from failure-to-comply through to reckless conduct. Body-corporate maxima are substantial and indexed; the current maximum follows the prevailing schedule of the responsible regulator.
Who this is for
- →Pipeline commissioning contractors carrying out cleaning, dewatering, drying, purging and gas-in.
- →Pre-commissioning and nitrogen-purging specialists preparing pipelines for service.
- →Pipeline operators and commissioning engineers planning and overseeing the gas-in sequence.
- →Operators and technicians managing vent points and atmospheric monitoring during commissioning.
- →PCBU safety managers and supervisors coordinating the SWMS, the commissioning permit and emergency response.
What you receive
- ✓Editable Microsoft Word document (.docx) fully compatible with Microsoft Word 2016 and newer, Google Docs, and LibreOffice Writer.
- ✓Title page with editable fields for PCBU name, ABN, site address, project name, principal contractor details, and document revision date.
- ✓Hazard register with the pipeline pre commissioning hazards — each with a documented consequence, inherent risk rating on a 5x5 likelihood-consequence matrix, hierarchy-of-control measures, and residual risk rating.
- ✓Purging and gas-in sequence prompts referencing the AS 2885 suite and the commissioning procedure, atmospheric and oxygen monitoring record fields for vents and confined spaces, and a vent-management and ignition-control section.
- ✓Competency verification table for the specialised roles, and a respiratory protection selection and fit-test record per AS/NZS 1715 where relevant.
- ✓Worker consultation record per the model WHS Act consultation duty and a worker sign-on register (blank, expandable).
- ✓Applicable legislation and Codes of Practice schedule pre-populated for the model WHS jurisdiction with a state-variance reference table covering the harmonised states, plus Victoria.
- ✓Emergency procedure template and a revision log.
Worked example
A commissioning contractor is bringing a newly tested high-pressure gas pipeline into service through a pre-commissioning sequence of cleaning, dewatering, drying and then purging and gas-in. Because the work is on a fuel line, gas-in can create a flammable atmosphere, and some steps require confined space entry, a SWMS is prepared and the work follows the AS 2885 suite and the project commissioning procedure. The purging sequence is designed so that air and flammable product never mix into an explosive atmosphere — the line is inerted with nitrogen before product is introduced — and continuous atmospheric monitoring at vents and the work area tracks flammable gas and oxygen, with oxygen monitoring for asphyxiation because nitrogen is used. Venting is directed to safe locations away from people and ignition sources, vent points are managed and signed, and ignition sources are excluded from the gas-in area. Where a vessel or pit must be entered, the confined space controls apply with atmospheric testing, ventilation, an entry permit and rescue arrangements, recognising the inert-atmosphere asphyxiation hazard. A permit-to-work governs the sequence, exclusion zones are set, workers wear flame-resistant clothing for gas-in and carry gas and oxygen detection, and the commissioning records and monitoring results are retained.
Related legislation
- Model Work Health and Safety Act — primary duty of care; the duty to consult workers; the reckless-conduct offence; and notifiable-incident provisions, as enacted in each jurisdiction.
- Model Work Health and Safety Regulations — Section 291 high risk construction work, including work on or near chemical or fuel lines, in a potentially flammable atmosphere, and in or near a confined space; and the SWMS preparation and review duties, as enacted in each jurisdiction.
- AS 2885.3 Pipelines: Gas and liquid petroleum (Operation and maintenance); AS 2885.0 General requirements.
- Pipeline safety legislation administered by the relevant state pipeline or energy safety regulator applies to commissioning of licensed transmission pipelines.
- Victoria operates under the Occupational Health and Safety Act 2004 and the Occupational Health and Safety Regulations 2017, with the high risk construction work and pipeline provisions applying in place of the model instruments.
Frequently asked questions
What does pipeline pre-commissioning involve?
Pre-commissioning prepares a newly constructed and tested pipeline for service through cleaning and gauging, dewatering after hydrostatic testing, drying, and then purging and filling with product or an inert medium. The highest-risk steps are purging and gas-in, when flammable product is introduced into a line that contains air and when inert media such as nitrogen are used, creating flammable-atmosphere and asphyxiation hazards.
How is an explosive atmosphere prevented during gas-in?
By following an engineered purging and gas-in sequence — typically inerting the line with nitrogen before flammable product is introduced — so that air and product are never allowed to mix into an explosive atmosphere. Continuous atmospheric monitoring at vents and the work area confirms the sequence is working, and ignition sources are excluded from the gas-in area.
Why is nitrogen purging an asphyxiation hazard?
Nitrogen and other inert media displace oxygen, and at vent points and in any confined space they can create an oxygen-deficient atmosphere that causes rapid loss of consciousness without warning. Oxygen monitoring, controlled venting to safe locations, and supplied-air respiratory protection for any oxygen-deficient or confined atmosphere manage that hazard.
Is confined space entry involved in pre-commissioning?
It can be, where a vessel, pit or other confined space must be entered for a commissioning step. In those cases the confined space controls apply — atmospheric testing, forced ventilation, an entry permit, a standby person and rescue arrangements — with particular attention to the asphyxiation hazard from inert media used in purging and drying.
What standard governs pipeline pre-commissioning?
Pre-commissioning of high-pressure pipelines carrying gas and liquid petroleum is carried out under the AS 2885 suite and the project's commissioning procedures. The SWMS sits alongside those, addressing the work health and safety controls for the flammable-atmosphere, asphyxiation, pressure and confined space hazards of bringing the line into service.