Access to dangerous goods training for firefighters in remote areas is limited for financial and logistical reasons. Virtual reality (VR) is a promising solution for this challenge as it is cost-effective, safe, and allows to simulate realistic scenarios that would be dangerous or difficult to implement in the real world. However, rigorous evaluations of VR training tools for first responders are still scarce. In this exploratory user study, a simple VR training tool involving two dangerous goods scenarios was developed. In each scenario, trainees learned how to safely approach a jackknifed truck with a trailer and how to collect and communicate information about the transported materials. The tool was tested with a group of 24 professional firefighter trainees (n = 22) and instructors (n = 2), who each completed the two training scenarios. The main goal of the study was to assess the usability of the VR tool in the given scenarios. Participants provided feedback on cybersickness, perceived workload, and usability. They also filled out a knowledge test before and after the VR training and gave feedback at the end of the study. The VR tool recorded task completion duration and participants' navigation and use of tools events. Overall, the tool provided good usability, acceptance, and satisfaction. However, a wide range in individuals' responses was observed. In addition, no post-training improvement in participants' knowledge was found, likely due to the already high level of knowledge pre-training. Future directions for improving the VR tool, general implications for other VR training tools, and suggestions for future research are discussed.