Increasing productivity along the development and verification process of safety-related projects is an important aspect in today’s technological developments, which need to be ever more efficient. The increase of productivity can be achieved by improving the usability of software tools and decreasing the effort of qualifying the software tool for a safety-related project.For safety-critical systems, the output of software tools has to be verified in order to ensure the tools’ suitability for safety-relevant applications. Verification is particularly important for test automation tools that are used to run hardware-in-the-loop (HIL) tests of safety-related software automatically 24/7. This qualification of software tools requires advanced knowledge and effort. This problem can be solved if a tool is suitable for developing safety-related software. This paper explains how this can be achieved for a COTS test automation tool.Maximizing the productivity of a software tool’s use involves more than just considering the pre-qualification of the tool in accordance to safety standards. Enhancements in the tool’s usability can also increase the productivity. Test automation tools usually let users develop tests by dragging blocks that define test steps. Signal-based tests are an advancement of this method, which is described in this paper. The aim of signal-based testing is to define test descriptions as if sketching graphs on a sheet of paper with a plotter-like editor to intuitively describe stimulus signals and reference signals as a sequence of signal segments, thereby lowering the initial hurdle towards setting up an efficient test automation.