An inspection finds the defect. Engineering assurance decides what it means: whether the crack can be monitored or must be repaired, what the repair must achieve, and whether the repaired asset can be safely returned to service. Those decisions carry the legal weight, and they should be made by engineers with the evidence in front of them.
We provide engineering review across mobile plant, lifting equipment and fixed structures — from a single defect assessment to documented return-to-service sign-off after major repair.
Inspection scope
- Defect assessment
- Significance of cracks, deformation, wear and corrosion against the design basis, load spectrum and consequence of failure.
- Repair specification
- Repair scope, weld procedure requirements to AS/NZS 1554 and AS/NZS 2980, material and NDT acceptance criteria.
- Repair verification and return to service
- Review of repair records, witness of NDT and load tests, and issue of a documented return-to-service statement.
- Modification review
- Assessment of attachments, structural changes and non-OEM components for effect on design registration, stability and structural capacity.
- Fitness-for-service and life extension
- Assessment of ageing plant and structures for continued operation, including monitoring regimes and inspection intervals.
- Incident investigation support
- Independent technical review of structural or mechanical failures, including evidence preservation and reporting.
What you receive
- Engineering assessment report with basis, assumptions, standards applied and conclusion
- Repair specification and inspection and test plan
- Return-to-service statement identifying the asset, repair scope and verification evidence
- Monitoring plan and re-inspection interval where a defect is accepted in service
- Modification assessment with any registration or documentation actions required
Applicable standards and regulations
| Reference | Title | Relevance |
|---|---|---|
| AS 4100 | Steel structures | Strength, serviceability and fatigue assessment basis for steel structures. |
| AS 3990 | Mechanical equipment — Steelwork | Design basis for machine steelwork and support structures. |
| AS/NZS 1554.1 and 1554.5 | Structural steel welding | Weld category, procedure and acceptance requirements for repairs. |
| AS/NZS 2980 | Qualification of welders for fusion welding of steels | Welder qualification underpinning structural repair welds. |
| AS 1418.1 | Cranes, hoists and winches — General requirements | Design basis for assessing crane structure defects and modifications. |
| AS 2294 series and ISO 3471 / ISO 3449 | Earth-moving machinery — ROPS and FOPS | Assessment of damage or modification to operator protective structures. |
| AS/NZS 3788 | Pressure equipment — In-service inspection | Fitness-for-service and repair requirements for pressure equipment. |
Evidence base for procurement
Public sources · reviewed 19 Sep 2026These regulator and standards sources provide the public basis for the inspection context on this page. They describe requirements and application context; they do not claim that Mining Inspection Australia holds a qualification, accreditation or project history.
Safe Work Australia
The model framework for plant duties, inspection, maintenance and records; check the adopted law in the relevant jurisdiction.
Safe Work Australia
Risk controls, regular inspection and testing, repair or replacement of plant, and the records that support those controls.
Typical findings
- Repair welds carried out without a qualified procedure or post-weld NDT
- Cracks previously ground out and painted over without assessment
- ROPS/FOPS structures drilled, welded or modified without OEM or engineering approval
- Attachments and counterweights fitted outside the design load chart
- Assets operating past their design working period without a life assessment
When to inspect
- An inspection or NDT report has identified a rejectable defect
- A structural repair is planned or has been completed
- Plant has been modified, re-rated or fitted with non-OEM attachments
- A regulator, principal contractor or insurer requires engineering sign-off
- An asset is approaching or past the end of its design working period
Frequently asked questions
When does a defect need an engineering assessment rather than just repair?
When the defect is in a primary structural member or safety-critical component, when the repair will change the original design (material, geometry or welding), when a defect is to be accepted in service and monitored, or when the asset is design-registered. In each case the decision needs to be documented by an engineer.
What does a return-to-service statement include?
Identification of the asset and defect, the repair specification followed, welder and procedure qualifications, NDT and any load test results, and a signed statement that the asset is fit to return to its intended service, with any conditions or monitoring requirements.
Can you assess a modification made by a previous owner?
Yes. Undocumented modifications are common on second-hand plant. We assess the modification against the original design basis and applicable standard, and advise what documentation, testing or rectification is required.
Do you provide the repair as well?
No. We specify, verify and certify repairs so that the assessment remains independent of the repairer.