Safety-Critical Systems CTEL-TM-SM Practice Questions (Page 1)

Questions 1–5

1. 1application · medium

   A test manager for a SIL 3 industrial control system must report test progress to stakeholders. The stakeholders want to know whether the system is ready for release. Which metric set provides the most meaningful indication of safety readiness?

   • ANumber of test automation scripts and the time spent on test execution.
   • BRequirements coverage percentage and the number of open safety-critical defects.
   • CTotal number of test cases executed and the total number of testers on the team.
   • DLines of code written and the number of code reviews completed.
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2. 2foundation · easy

   Which statement correctly differentiates verification from validation in a safety-critical context?

   • AVerification checks that the system meets its specified requirements, while validation checks that the system meets the user's needs and expectations.
   • BVerification is performed by developers, while validation is performed by testers.
   • CVerification is only done at the end of development, while validation is done throughout.
   • DVerification is a static activity, while validation is a dynamic activity.
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4. 3expert · hard

   A company is developing a braking system for a new electric vehicle and must comply with ISO 26262. The system is classified as ASIL D. The team is considering using a third-party software component for the braking algorithm. The component was developed for a non-automotive application and has no safety certification. What is the most appropriate action for the test manager?

   • AUse the component and rely on system-level testing to catch any defects.
   • BUse the component but document it as a 'proven in use' argument to justify its safety.
   • CUse the component as-is because it has been widely used in other applications and is likely reliable.
   • DDo not use the component unless it can be re-qualified to ASIL D, which may require extensive additional testing and documentation.
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5. 4expert · hard

   A team is testing a satellite attitude control system. The system uses reaction wheels and thrusters to maintain orientation. The test environment includes a simulation of the space environment, but the team has limited access to the actual hardware. The test manager must plan the test environment to maximize confidence in the system's behavior. Which approach is most appropriate?

   • AUse a hardware-in-the-loop simulation that includes the actual flight software and representative hardware for critical components.
   • BRely on pure software simulation because the space environment cannot be accurately replicated on Earth.
   • CUse a mock-up of the hardware that does not include all sensors and actuators.
   • DTest only the actual hardware in a vacuum chamber to replicate space conditions.
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6. 5application · medium

   A team is testing an autonomous vehicle's obstacle detection system. The system uses cameras and LiDAR to detect pedestrians. The test manager must plan the test environment. Which approach best ensures that the test environment accurately represents operational conditions for this safety-critical system?

   • AUse only physical test tracks because they provide the most realistic conditions.
   • BUse a combination of simulation for edge cases and physical test tracks for real-world sensor validation.
   • CRely exclusively on simulation to test millions of scenarios quickly and safely.
   • DTest only in a controlled lab with artificial lighting and static obstacles.
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