Overview
IEC 62741:2015, titled Demonstration of Dependability Requirements - The Dependability Case, is an international standard developed by the International Electrotechnical Commission (IEC). This standard provides comprehensive guidance on creating, applying, and maintaining a dependability case throughout the lifecycle of a system. The dependability case serves as an evidence-based, traceable argument to demonstrate that a system meets specified dependability requirements, including reliability, availability, maintainability, supportability, usability, testability, and durability.
The standard is intended for use in scenarios where a customer commissions a supplier to deliver a system that adheres to clear dependability requirements and continues through the management of the system until its retirement. IEC 62741:2015 also accommodates adaptations for different application contexts, such as regulatory review or ongoing operational updates.
Key Topics
Dependability Requirements
- Definition and establishment of system dependability goals aligned with customer and stakeholder needs.
- Incorporation of key properties: reliability, availability, maintainability, supportability, usability, testability, and durability.
Structure of the Dependability Case
- Presentation of a structured, reasoned argument supported by evidence gathered throughout the system’s lifecycle.
- Inclusion of claims, sub-claims, and supporting arguments about dependability, clearly linked to documented evidence.
Evidence Framework
- Systematic identification of what evidence will be, or has been, produced to show that risks have been addressed and requirements met.
- Utilization of evidence from a variety of sources such as testing, operation data, expert opinion, modeling, and previous usage.
Progressive Assurance
- The dependability case is developed and updated through all stages: concept, development, realization, utilization, enhancement, and retirement.
- The standard emphasizes reducing uncertainty by progressively building a body of evidence.
Stakeholder Involvement and Communication
- The dependability case acts as a central communication tool among customers, suppliers, users, regulators, and certification bodies.
- Roles and responsibilities are clarified for all participants across the system’s lifecycle.
Applications
IEC 62741:2015 is practically valuable across a wide range of industries and projects where dependability assurance is critical:
- Supply Chain Contracts: Ensures that the supplier delivers a system meeting agreed dependability standards, reducing risk of failure and associated costs.
- Certification and Regulatory Review: Certification bodies and regulators use the dependability case to assess compliance for approval or licensing.
- Lifecycle Management: Facilitates ongoing monitoring, updates, and evidence gathering to address changes in requirements, environment, or system use.
- Complex Systems and Novel Technologies: Especially beneficial for high-value, low-volume systems where direct dependability testing may be impractical.
- Operational Adaptation: Supports users who modify or extend a system’s application by enabling updates to the dependability case, ensuring continued compliance.
Related Standards
IEC 62741:2015 complements and is often used alongside other international standards related to dependability, risk management, and quality assurance, including:
- IEC 60050-192: International Electrotechnical Vocabulary – Dependability
- IEC 60300-1: Dependability Management – Guidance for Management and Application
- ISO 31000: Risk Management – Principles and Guidelines
These standards provide foundational terminology, management processes, and risk assessment methodologies that underpin the development and maintenance of a robust dependability case.
Keywords: dependability case, IEC 62741, dependability requirements, reliability, availability, maintainability, supportability, usability, testability, durability, evidence framework, progressive assurance, lifecycle management, certification, risk management, dependability standards.
