Yajue, WuAbdulaziz, AlQahtani2026-01-072025Harvard standardhttps://hdl.handle.net/20.500.14154/77809Hydrogen is increasingly employed as a clean energy source with the potential to replace fossil fuels and reduce greenhouse gas emissions. Facilities for producing and transmitting hydrogen are growing globally as a result of the global push for sustainable energy. High pressure is often used in pipeline operations, and leaks can quickly combine with air to create extremely flammable clouds that, if ignited, can cause devastating fires or explosions.Abstract Hydrogen is increasingly employed as a clean energy source with the potential to replace fossil fuels and reduce greenhouse gas emissions. Facilities for producing and transmitting hydrogen are growing globally as a result of the global push for sustainable energy. High pressure is often used in pipeline operations, and leaks can quickly combine with air to create extremely flammable clouds that, if ignited, can cause devastating fires or explosions. Environmental factors have a significant impact on hydrogen dispersion and related hazards. Hydrogen pipelines in Saudi Arabia face particular difficulties due to the country's arid climate, sandstorms, and strong winds. These include sand abrasion-induced external erosion or corrosion, delayed leak detection, and elevated ignition risk brought on by electrostatic charges. Strong winds, however, also encourage broader horizontal dispersion, which may lessen concentrations in certain areas. On the other hand, the UK has little exposure to sandstorms and mild wind conditions. In the event of a leak, this raises the possibility of a localized buildup of highconcentration flammable clouds even though it lowers the risks of external erosion. This study compares the impact of sandstorms and wind on the safety of hydrogen pipelines in the UK and Saudi Arabia. A risk assessment methodology was used, combining a review of the literature, qualitative risk analysis, and PHAST software-based dispersion modelling in a varying meteorological condition. There is currently little information available on these environmental effects, and current approaches frequently ignore these local risks, which results in erroneous risk assessments46enAbstractThesis