Coverage

Coverage, in the context of safety-critical software development, measures how much of the intended functionality, code, or design has been thoroughly checked. For example, if you are testing software, code coverage metrics indicate what percentage of your source code has been executed by your tests. Similarly, requirements coverage shows how many of your specified requirements have corresponding tests to verify their implementation. The goal is to identify gaps in testing and analysis, helping to build confidence that the system will behave as intended under all specified conditions.

Coverage is paramount for functional safety because it directly contributes to demonstrating that a system meets its safety objectives. Standards like ISO 26262 for automotive, IEC 61508 for industrial applications, and DO-178C for avionics emphasize the need for adequate coverage. Without sufficient coverage, there is a higher risk of latent defects remaining undetected, which could lead to hazardous situations in a deployed system. By systematically measuring and improving coverage, organizations can provide objective evidence that their processes are thorough, thereby building trust in the safety of their products.

Within the ISO 26262 standard, coverage is a key aspect of various activities, particularly in verification and validation. For software, the standard specifies different levels of code coverage, such as statement coverage, branch coverage, and Modified Condition/Decision Coverage (MC/DC), depending on the Automotive Safety Integrity Level (ASIL) of the component. Higher ASILs demand more rigorous coverage metrics.

Beyond code, ISO 26262 also requires comprehensive requirements coverage to ensure that all safety requirements have been verified. It's not just about running tests; it's about demonstrating that the tests adequately address the defined safety functions and their potential failure modes.

When qualified with Validas, you not only gain confidence in your tools but also meet compliance with safety standards such as ISO 26262 (up to ASIL D), IEC 61508 (up to SIL 4), and DO-330 (for TQL 5). The QKit qualifies the tools in your environment and provides a Tool Safety Manual to handle known limitations.

Validas offers two approaches, One-Time Qualification and Qualification Kit (QKit). Both options ensure compliance, reduce the need for mitigation, and support successful certification outcomes.