Failure Modes, Effects and Criticality Analysis (FMECA) assessments have become a foundational pillar for safe and efficient diving operations across the global subsea industry. As systems grow in complexity and automation becomes more deeply integrated into diving operations, the need for a structured, defensible, and comprehensive approach to identifying equipment failure modes has never been greater.
At Namaka Subsea, we have long championed the adoption of rigorous FMECA methodologies aligned with the latest industry guidance. Our experience in developing and applying IMCA D039 FMECA Guide for Diving Systems, together with our assistance with the development and adherence to the IOGP Diving System Assurance Recommended Practice (Report 468), and our longstanding involvement in IMCA and IDIF diving committees, uniquely positions us to support operators and contractors in strengthening the reliability of their diving systems.
Why FMECA Matters in Diving Operations
A diving system FMECA provides a systematic evaluation of how individual component failures, whether mechanical, electrical, hydraulic, control system based, or procedural, can effect diver safety, system integrity, equipment reliability and operational continuity.
Its purpose is not solely to catalogue failures, but to quantify criticality or failure modes, identify current and missing mitigation, and highlight where design improvements or operational controls are required.
Several high‑profile incidents in the industry, most notably the Byford Dolphin tragedy of 1983, demonstrated what can occur when failure modes are not adequately assessed. Where FMECA is correctly applied, such vulnerabilities, whether caused by design flaws, human error, or insufficient redundancy, can often be identified long before they pose a risk to personnel.
Industry Drivers and Evolving Requirements
Today, FMECA is not just considered best practice, in many global regions it is a mandatory requirement. Prominent organisations shaping these expectations include:
- IOGP – Diving Recommended Practice (Report 411) and Diving System Assurance (Report 468).
- IMCA – Guidance such as IMCA D039 (FMECA Guide), D023 (Surface Supplied Air Systems), D024 (Saturation Systems), D037 (Surface Supplied Mixed Gas Systems), D040 (Mobile/Portable Surface Supplied Systems), and D053 (Hyperbaric Reception Facilities).
- IMO, , ABS, BV, DNV, Lloyd’s Register – Each providing regulatory or classification requirements.
- National regulators such as the HSE (UK), Department of Employment and Labour (South Africa) and NOPSEMA (Australia).
These bodies collectively emphasise that a FMECA must:
- Reflect real operational conditions
- Consider support vessel interfaces
- Capture all system‑level failure modes
- Remain a live document throughout the lifecycle of the diving system
- Be validated through periodic proving trials and verification tests
Common Gaps Found in Diving System FMECA Reviews
During assurance audits, Namaka Subsea routinely identifies significant deficiencies within existing FMECA documentation, including:
- Failure to follow IMCA D039 methodology
- Omission of vessel‑system interfaces
- No reference to operating or emergency procedures
- Inaccurate, outdated, or incomplete system drawings
- Lack of consideration for planned maintenance systems
- No evidence of proving trials
- Misclassification or absence of Safety Critical Elements (SCEs)
- Limited assessment of automation‑related failure modes
Such gaps may compromise diver safety, reduce system resilience, or even lead to non‑conformance with regulatory expectations.
Namaka Subsea’s Methodology: Enhancing Safety and Reliability
Our approach builds on IMCA and IOGP guidance but places additional emphasis on diver and topside personnel safety and the identification of single point failures (SPFs).
Key Components of the Namaka FMECA Process
- Systematic Failure Mode Identification
Each subsystem, pneumatic, electrical, hydraulic, communication, pressure systems, control systems, launch & recovery, is broken down into components. For each we analyse:
- Failure mode
- Initiating cause
- Means of detection
- Operational effect
- Criticality (pre‑ and post‑mitigation)
- SPF impact and mitigation
- Performance Standard Assessment
Aligned with IMCA and IOGP requirements, we verify:
- Functionality – Does the system do what it must?
- Reliability – Does it do so consistently?
- Availability – Is it operational when needed?
- Survivability – Can it protect life under abnormal conditions?
- Proving Trials
Mitigations must be demonstrated through real‑world testing. Trials confirm:
- The system performs as designed
- Emergency procedures and equipment are effective
- Operators are competent and familiar with system behaviours
- Lifecycle Management
A FMECA must evolve. Namaka’s assurance process ensures:
- Annual verification
- Update after any system change or mobilisation
- Integration into maintenance, operations, and emergency procedures
- Use as a training and competency development tool
Competence of FMECA Practitioners
A high‑quality FMECA requires multi‑disciplinary expertise. A competent assessment team should include:
- FMECA lead practitioner
- Mechanical engineer/technician
- Electrical/control systems specialist
- Automation systems engineer
- Experienced diving supervisor or life support specialist
This ensures both the technical elements and the operational impacts of failures are correctly understood.
FMECA as a Strategic Safety Asset
When executed properly, a FMECA becomes much more than a technical document. It becomes:
- A critical risk management tool
- A foundation for operational and emergency procedures
- Evidence of due diligence for regulators and clients
- A continuous improvement driver
- A reference point for maintenance, competence, and assurance
It ensures that any diving system, new or existing, remains fit for purpose, compliant with industry standards, and safe throughout its operational life.
Our Commitment to Industry Excellence
Namaka Subsea continues to support operators, contractors, and system manufacturers in exceeding global expectations for diving safety. Our commitment to IOGP and IMCA, combined with decades of practical experience, ensures that our FMECA work is robust, defensible, and aligned to the latest industry developments.
Whether conducting a full new FMECA, reviewing an existing system, performing a gap analysis, or supporting annual assurance audits, our goal is simple:
Protect divers. Strengthen systems. Improve operational integrity.