This report describes the results of the study into electrostatic discharge under realistic conditions that can lead to the ignition of hydrogen-air mixtures outside gas transport and distribution systems. This was prompted by the increasing transport and distribution of hydrogen, where the lower (concentration-dependent) minimum ignition energy (MIE) and broader flammability limits lead to a higher susceptibility to ignition compared to natural gas (at certain concentrations). This raises the question of the extent to which electrostatic discharge can lead to the ignition of hydrogen-air mixtures in practice, and to what degree this risk is relevant for working on gas infrastructure. This involves the use of components such as those applied by Dutch grid operators. The research is based on a combination of literature review and experiments. Initially, the extent to which electrostatic discharge can occur to components in the gas network was investigated. Subsequently, it is determined experimentally under which conditions this discharge can actually lead to the ignition of a hydrogen-air mixture (during maintenance activities or outside the pipeline). The results demonstrate that electrostatic discharge from a person to a component can occur under realistic conditions. So-called conductive components, such as metal pipes and valves, exhibit consistent discharge even at relatively low voltage levels (2–4 kV). These voltages fall within a range which can quite easily be generated by people during everyday activities, particularly under dry conditions (10% LFL), personal protective equipment must be used, and professional competence is prioritized through training, instructions and supervision. It can therefore be concluded that the risk of ignition due to electrostatic discharge is sufficiently mitigated in current practice. Safety is based partly on avoiding the circumstances under which ignition can occur, and not on excluding static electricity as a physical ignition mechanism. The results provide insight into the underlying mechanisms and confirm that electrostatic ignition is physically plausible but is operationally controlled within current working practice. Overall, the factors underline the importance of continued attention to and correct application of existing safety measures, particularly given the higher susceptibility of hydrogen to potential ignition compared to natural gas.

Dit project is medegefinancierd door TKI Nieuw Gas | Topsector Energie uit de PPS-toeslag onder referentienummer TKI2025-HyDelta.