Change Impact Analysis (CIA) during software evolution of safety-critical systems is a labor-intensive task. Several authors have proposed tool support for CIA, but very few tools were evaluated in industry. We present a case study on ImpRec, a recommendation System for Software Engineering (RSSE), tailored for CIA at a process automation company. ImpRec builds on assisted tracing, using information retrieval solutions and mining software repositories to recommend development artifacts, potentially impacted when resolving incoming issue reports. In contrast to the majority of tools for automated CIA, ImpRec explicitly targets development artifacts that are not source code. We evaluate ImpRec in a two-phase study. First, we measure the correctness of ImpRec's recommendations by a simulation based on 12 years' worth of issue reports in the company. Second, we assess the utility of working with ImpRec by deploying the RSSE in two development teams on different continents. The results suggest that ImpRec presents about 40 percent of the true impact among the top-10 recommendations. Furthermore, user log analysis indicates that ImpRec can support CIA in industry, and developers acknowledge the value of ImpRec in interviews. In conclusion, our findings show the potential of reusing traceability associated with developers' past activities in an RSSE.