How safe is your hydrogen-powered car? - some safety and human factors issues

Scientists have shown that the causes of climate change are mainly due to carbon dioxide (CO₂) and other emission gases generated by burning fossil fuels. Amongst all sectors, tailpipe pollution is always a keyword that cannot be avoided in any climate-related conversations. It has been considered a significant contributor to global air pollution and eventually global warming. Industrial professionals, researchers, and engineers advocate hydrogen as a potential fuel for delivering energy instead of fossil fuel due to its chemical nature. Nowadays, various models and sizes of Hydrogen Fuel Cell Vehicles (HFCVs) are running on the road.

However, the safe retrofitting of fuel cells into areas with little prior experience with hydrogen, especially domestic environments, can raise many new issues. In transport applications, people are most likely to associate hydrogen fuel with the Hindenburg disaster (1937) and mistakenly attribute the explosion to hydrogen. This misunderstanding may steer public perception about hydrogen fuel and mislead the safety judgement. With the growing awareness of HFCVs among a broader audience, extending beyond the Subject Matter Experts (SMEs), their safety has become an ongoing debate to the general public. Therefore, this thesis aims to study the safety issues related to hydrogen fuel cell vehicles from a human factor perspective. The ultimate goal is to understand the potential impacts of HFCV usage on the future road transport system with regard to safety.

The first study of this research is a quantitative study investigating the public safety concern of different vehicle powertrains. It revealed that the awareness of the specifics of hydrogen fuel cell vehicles is not widespread amongst the general public. It is difficult for people to comment on any specific aspect of HFCV safety concerns as they have not had such an experience. Hence, the outcomes of this study also suggested that the second study should provide participants with a certain level of HFCV driving experiences.

The second study of this research assesses the changes in drivers’ perceptions of the HFCV and associated consequences before and after an HFCV test drive. The outcomes of this study revealed that experiencing vehicle performance differences and being able to know hydrogen-related knowledge are the two key factors that cause drivers’ behaviour changes. The impacts of different perception changes are discussed, and potential improvement strategies are also suggested.

The third study of this research investigates the UK emergency responders’ perceptions of hydrogen fuel cell vehicles. This is because, when a Road Traffic Collision (RTC) occurs involving an HFCV, the public will rely on emergency personnel to handle the collision and ensure the safety and efficient rescue of the drivers, passengers, and other road users. However, emergency responders’ perceptions have never been explored and better understood. The results revealed that firefighters have different perceptions of the HFCVs than the general public. Further analysis indicates the differences between their perceptions of HFCV safety and engineers/general public perceptions. Recommendations to address these concerns are discussed as well as the political implications.

Finally, all the findings from these studies are summarised, discussed, and concluded according to the scope of the thesis and research questions, including descriptions of the limitations and identifications of potential improvement pathways.