In Ireland, transportation accounts for 36% of total energy consumption, mainly due to private cars and heavy goods vehicles, responsible for 70% of transportation sector carbon emissions. Despite some progress in new car carbon intensity, petrol and diesel vehicles remain dominant. Hydrogen (H2) is a non-toxic, highly combustible gas, holds significant potential, especially for heavy-duty vehicles, as a mean to reduce carbon emissions. However, realising this transition requires targeted policies and infrastructure development. A crucial tool for evaluating hydrogen-based transportation is a comprehensive life cycle assessment (LCA). This assesses the full process, from production, transport and use, to disposal, providing insights into environmental impact, including carbon footprint, energy consumption, air pollution, material use and vehicle efficiency. By assessing different hydrogen sources like green and blue hydrogen, the LCA informs decision-makers and aids in developing sustainable transportation strategies. This work highlights the importance of the method to transporting the hydrogen fuel. Fuelling stations show a substantial carbon footprint (1.75 kg CO2 eq./kg H2), while hydrogen transportation through pipelines has minimal emissions (0.0000235 kg CO2 eq./kg H2) compared to moving it in compress cylinders by diesel truck. This underscores the need for careful planning to minimise environmental impacts when deploying hydrogen in transportation systems.