By Byron Raal, CAS Founder-Editor · Last updated 4 June 2026 · About the author
Western Australia moved onto the harmonised WHS laws on 31 March 2022, so if you last registered plant here under the old rules, the logic has changed. Pressure vessel registration now runs under the Work Health and Safety (General) Regulations 2022, administered by WorkSafe WA, now within the Department of Local Government, Industry Regulation and Safety, and it mirrors the eastern states: item registration for hazard level A, B or C vessels, design registration for A, B, C or D.
This page covers the WA position: which receivers trigger registration, how the hazard level is calculated, the interstate design recognition rule that saves duplicate paperwork, and the registration carve-out for serially produced vessels. It is written for plant managers, maintenance engineers, and procurement teams running compressed air in Western Australia.
Design registration, item registration, and inspection in WA
WA treats three activities as separate obligations under Schedule 5 of the regulations: design registration (Division 1), item registration (Division 2), and ongoing in-service inspection.
Design registration covers the vessel design. WorkSafe WA accepts a design that demonstrates compliance with published technical standards or engineering principles; compliance with AS 1210:2010 Pressure Vessels and the AS/NZS 1200 framework is not itself legislated in WA, but it is the reasonably practicable way to meet the duty. Design registration covers every vessel built to that drawing.
Item registration under Regulation 246 covers the individual serial-numbered vessel in your plant room, held by the person with management and control of the workplace. It is site-specific.
In-service inspection under AS/NZS 3788:2024 Amd 1:2025 is the ongoing obligation to inspect the vessel on a defined cadence. Inspection is not registration.
AS 4343 hazard level: what triggers WA registration
Registration turns on the hazard level under AS 4343:2014 Pressure Equipment Hazard Levels, which Schedule 5 of the WA regulations references directly. Five levels run A (highest) to E (lowest), and registration follows the level, not the tank size alone.
Under Clause 2.2.1 of AS 4343:2014, H = P × V × Fc × Ff × Fs, where P is design pressure in MPa, V is volume in litres, Fc is 10 for a gas, Ff is 1.0 for non-harmful gas, and Fs is 1 for standard service. For a clean compressed air receiver this simplifies to H = 10 × P (MPa) × V (L).
Worked example: 1,000 L receiver at 1,200 kPa design pressure
- Design pressure, P = 1,200 kPa = 1.2 MPa
- Volume, V = 1,000 L
- H = 10 × 1.2 × 1,000 = 12,000
- 12,000 is in the range 10,000 to under 316,227,766, so the vessel is hazard level B
Hazard level B requires both design and item registration in WA, subject to the serially produced carve-out below. The table maps class boundaries for clean compressed air at standard service across four common working pressures.
| Design pressure | Level E (no registration) | Level D (design only) | Level C and above (design and item) |
|---|---|---|---|
| 700 kPa (0.7 MPa) | up to ~45 L | above 45 to 143 L | above 143 L |
| 800 kPa (0.8 MPa) | up to ~40 L | above 40 to 125 L | above 125 L |
| 1,000 kPa (1.0 MPa) | up to ~32 L | above 32 to 100 L | above 100 L |
| 1,200 kPa (1.2 MPa) | up to ~26 L | above 26 to 83 L | above 83 L |
What WA registers, and the serially produced carve-out
In WA, Schedule 5 Division 1 requires design registration for pressure equipment, other than pressure piping, at hazard level A, B, C or D. Schedule 5 Division 2 requires item registration for pressure vessels at hazard level A, B or C, except serially produced vessels. That serially produced exception is the common compressed air case: the mass-manufactured receivers on package and tow-behind compressors are exempt from item registration even at a registrable hazard level, while the design still has to be registered. Run the hazard level calculation and confirm whether the vessel is serially produced before assuming item registration applies. A vessel whose hazard value sits exactly on a class boundary takes the lower hazard level (AS 4343 Clause 2.2.8).
Interstate design recognition: the WA paperwork saver
WA’s regulations require an item’s design to be registered, in WA or by the WHS regulator in another Australian state or territory, before the item is registered in WA. In practice this means a design already registered in New South Wales, Queensland, South Australia, or another harmonised jurisdiction is recognised in WA, so you do not re-register the design when a vessel or a fleet moves west. You still lodge the WA item registration for the physical vessel, and the in-service inspection obligation travels with the vessel regardless of where the design sits.
How to register plant in WA
Item registration is lodged with WorkSafe WA. You will need the design registration number (WA or interstate), the vessel’s identifying details, and the controlling-entity and site details. Because fees are set per financial year, price the job against the current WA plant and design registration guide and the WorkSafe WA fees schedule rather than a number from last year. Reg 246 sets out which items must be registered; WorkSafe WA also publishes exemption decisions under Regulation 246 where they apply. Unlike most harmonised states, WA does not require periodic re-registration of a registered item of plant: once registered it stays registered, provided you notify WorkSafe WA when the item’s key details change.
A note for WA mining operators
WorkSafe WA, now within the Department of Local Government, Industry Regulation and Safety, regulates mine-site work health and safety under the Work Health and Safety (Mines) Regulations 2022. A pressure vessel installed on a mine site is governed by those mines regulations rather than the general regulations alone, but WorkSafe WA remains the single regulator and registration is still administered through the WHS (General) Regulations 2022. If your receiver is on a mine site, confirm the mines-specific requirements with WorkSafe WA before you lodge. For surface industrial sites the general WHS (General) Regulations 2022 pathway above is the one that applies.
Who is responsible in WA
The person with management and control of the workplace holds item registration and books inspections; in leased and labour-hire arrangements this usually falls on the host site. The worker operating the plant must report defects and stop using unsafe equipment. The competent person under AS/NZS 3788:2024 Amd 1:2025 is the only role that can certify a vessel fit for continued service, combining a recognised credential (typically AICIP pressure equipment inspector credentialling) with documented experience.
CAS is an independent information and supplier-matching service. We do not inspect or lodge registrations; we connect you with a competent person and with inspection and replacement suppliers across WA who quote against your actual fleet.
Penalties for unregistered operation in WA
Operating a registrable pressure vessel without current registration is an offence under the Work Health and Safety Act 2020 (WA). Penalties scale by offence category, from failing to comply with a health and safety duty through to reckless conduct causing death or serious injury, and the figures are revised, so check the current Act. Enforcement usually begins with an improvement notice, escalates to a prohibition notice that locks the vessel out of service, and can lead to prosecution. Industrial insurers commonly require evidence of current registration and AS/NZS 3788 inspection as a condition of cover.
Next step: confirm your WA registration status
Walk the plant room, photograph every receiver nameplate legibly, and log the design registration number, design pressure, volume, and fabrication date for each into one spreadsheet. If a vessel or fleet has moved into WA from another state, check whether the existing interstate design registration covers you and lodge the WA item registration for the physical vessel. Run the AS 4343 hazard level on anything you cannot confirm. Anything missing is a remediation job.
If you need a competent person to inspect and register a fleet of receivers in WA, CAS connects you with vetted inspection and supply partners. Use the form below to outline what you have and where it is, and we route the enquiry to a supplier who can quote against your actual fleet.
Related reading on CAS: the national pressure vessel registration guide, air receiver tank sizing and selection, the Safe Work Australia compressed air compliance guide, and the compressed air systems hub. Registering in another state? See NSW, Victoria, Queensland, and South Australia.
Frequently Asked Questions
Did WA pressure vessel registration change when WA adopted the WHS laws?
Yes. WA moved onto the harmonised Work Health and Safety (General) Regulations 2022 on 31 March 2022. Pressure vessel registration now follows the model scheme: design registration for hazard level A, B, C or D, and item registration for A, B or C, except serially produced vessels. Operators who registered plant under the previous WA regulations should confirm their current obligations against the 2022 regulations.
Do I need to re-register a design if a vessel moves to WA from another state?
No. WA recognises a plant design registered by the WHS regulator in another Australian state or territory, so you do not re-register the design. You do lodge a WA item registration for the physical vessel, and the in-service inspection obligation travels with the vessel regardless of where the design is registered.
Who administers pressure vessel registration in WA?
WorkSafe WA, within the Department of Local Government, Industry Regulation and Safety, administers plant registration under the Work Health and Safety (General) Regulations 2022. Regulation 246 sets out the items of plant that must be registered. Mine-site pressure vessels may fall under the mining safety regime instead, so confirm the pathway if your vessel is on a mine site.
Are serially produced air receivers exempt from registration in WA?
Serially produced pressure vessels are excluded from item registration in WA even when the hazard level would otherwise require it, but the design still has to be registered. Mass-manufactured receivers on package and tow-behind compressors usually qualify; bespoke receivers usually do not. In-service inspection applies regardless.
Does a 1,000 L air receiver need registering in WA?
Usually yes. A 1,000 L receiver at 1,200 kPa design pressure has a hazard level of B under AS 4343:2014 (H = 10 x 1.2 x 1,000 = 12,000), which requires both design and item registration unless the vessel is serially produced. Run the hazard calculation and confirm the carve-out before you assume.
Related Resources
- Pressure Vessel Registration in Australia: the national overview and state-by-state comparison.
- Air Receiver Tanks Australia: sizing, selection, and AS 1210:2010 design compliance.
- Safe Work Australia Compressed Air Compliance Guide: the WHS framework behind state registration.
- Compressed Air for Mining: WA mining context for pressure equipment on site.
- All CAS Resources: the full reference library on Australian compressed air standards.
General information disclaimer. The information on this page is general in nature and provided for educational purposes only. It is not engineering, safety, or professional advice, and it does not account for the specifics of your site, equipment, or duty. Compressed air system design, pressure equipment selection, and regulatory compliance must be confirmed with a qualified engineer and the relevant work health and safety regulator before you act. Compressed Air Solutions is a publisher and referral service, not a licensed engineering practice, and accepts no liability for decisions made on the basis of this content. Verify all figures, standards references, and regulatory requirements against current primary sources.