
Hydrogen Safety and Improved Permit Processes, H2SIPP
The project studies how different types of obstacles to the implementation of hydrogen in the Nordic countries can be overcome, with a focus on permit processes, acceptance and hydrogen safety.
Within the project, material and reliability analyzes in the form of non-destructive testing will be carried out. The results will form the basis of a strategic plan within the safety and permit perspective for the Nordic region with the aim of maintaining leadership and benefiting from the technology developed so far in hydrogen gas for many years to come.
The Hydrogen Safety and Improved Permit Processes, H2SIPP project has a budget of SEK 18 million and has 14 parties from Sweden, Finland and Norway.
Project partners:
Luleå University of Technology, Lund University, Aalto University, Norwegian University of Science and Technology, Energigas Sweden, Zelk Energy, Skoogs Bränslen, Bodens Utveckling AB, Gällivare's business community, SSAB, Gen-H Oy, Hydri, Nordion Energi, AFRY.
Financiers:
Nordic Energy Research with the program Nordic Hydrogen Valleys as Energy Hubs, funded by the Swedish Energy Agency, Business Finland, and Innovation Norway.
Project summary
The overall goal with this project is to develop a strategy to delimit barriers for the implementation of hydrogen in the Nordic countries, from a permit, safety and social acceptance perspective – factors identified as key barriers in recent work. The focus is to support streamlining the permitting process in general and specifically for safety distance determination which are considered one of the major challenges for a broad implementation of hydrogen technologies. The work will be performed by researchers within hydrogen implementation, regulations and organization at LTU in co-operation with hydrogen safety researchers at LTH, material experts in Aalto Uni and researchers within safety at NTNU. The project is strongly supported by actors across the hydrogen value chain, who all witness of the acute need of improving the permit processes, safety analysis and connected barriers as social acceptance. For the analysis of decision-making permit processes, the project will rely on written materials, on stakeholder interviews and network analyses capturing, how the decision-making system on hydrogen de facto is organized, what institutional challenges involved actors identifies, and what is required to overcome them (in terms of new legislation and organization).
Comparing Sweden and Norway, where the experience of gas is much different due to the offshore industry, in this respect will provide valuable lessons for the future. As part of the engineering research, Aalto will add material safety and reliability analysis supported by tailormade plan for nondestructive testing (NDT). The NDT plan will be developed and validated in pipeline prototypes, made of materials and dimensions representative of real conditions. To improve the accuracy of safety distance determination, which is central for location and layout for new hydrogen infrastructure, semiempirical models will be developed for safety distances taking into account the radiative and buoyancy properties of H2-flames, which differs considerably from hydrocarbon flames.
Also, the potential of underground transport and accumulation of H2 will be included in the models for underground pipelines. These models will build upon existing hydrocarbon jet flame theory but will be adapted for properties that make existing models in some respects under-conservative and others over-conservative. All work will be the base to present a plan for the Nordics from the safety and permits perspective, to keep the lead and gain the advantages many years ahead.
Objectives

The project's overall objectives from the text above, with logos for implementing universities in Sweden, Finland and Norway, as well as the financier Nordic Energy Research within the program Nordic Hydrogen Valleys as Energy Hubs.
Social acceptance, political organization and hydrogen security - where do we stand today?
The expansion of the hydrogen system as a central part of the industry's green transition and an increased production of fossil-free energy requires not only new technical solutions but also many other conditions. The implementation of new technology means new societal challenges in terms of such issues as acceptance, security, and policy and permit processes, which in turn can constitute barriers to implementation. For example, today there is neither an expanded infrastructure, adapted legislation nor sufficient experience and knowledge of what the use of hydrogen means for both decision-makers and the public. The necessary societal structures and institutions for a large-scale, efficient implementation of various hydrogen applications are simply lacking. At the same time, it is emphasized from the industry that society's processes are often too slow and that decisions concerning central issues of detailed plans and environmental permits need to be rushed. This creates major challenges for both the legal and the political systems, which are currently not adapted to the new technology, and which also need to deal with the social acceptance of an increased use of hydrogen and the industrial and infrastructural consequences this entails.
The capacity of the current policy system to incorporate hydrogen as part of the energy system means that consideration must be given to the problem of fit* that can arise when new policy, to enable the construction of production facilities and transport pipelines, meets the pre-existing policy landscape*. The risk of policy clashes*, especially when overarching strategies are translated into political practice, is palpable. Incorporating hydrogen as a key component of the energy system is also intimately linked to broader issues of increased fossil-free energy production (for example, an expansion of wind power), which increases the complexity even more. Since the policy system that surrounds these issues also includes a number of different actors, in different policy areas and at different levels – from the national down to local actors and decision makers – the need for clear coordination and coherence* also becomes apparent. Finding ways to avoid isolated decision-making processes and to avoid or overcome coordination externalities* therefore becomes a key issue.
Another key issue that needs attention is social acceptance. This includes the attitudes of political decision-makers at local and regional level, where environmental and planning permits are determined and land use proposals are evaluated, relevant stakeholders such as land and property owners, rights holders and not least Sami representatives and the public. Previous research in other areas clearly shows that the lack of widespread social acceptance constitutes a significant obstacle to the implementation of both new projects and policies. How and why social acceptance varies, between different hydrogen applications and in different contexts, is therefore central to better understanding how acceptance issues can affect the possibilities for implementing hydrogen in the energy system.
In this project, the legal and political prerequisites for the implementation and development of various hydrogen applications are studied, such as permit and other decision-making processes, coordination of actors, policies and goals, as well as the social acceptance concerning both production facilities, storage and transport pipelines. The project begins with a mapping of current actors, decision-makers, authorities, organizations and industry, who are in various ways relevant players in hydrogen gas in Sweden, including their mutual relations in the form of coordination and collaboration, as well as of the current current (permit and decision -) the processes. The actors and their relationships will be illustrated using network maps. The actors' perceptions of the need for development and change in the current legal and policy systems are then analysed. This, together with analyzes of the social acceptance of both current and future hydrogen systems carried out in the form of focus groups/interviews and surveys, allows the project to provide sharp conclusions regarding what measures are necessary to enable a large-scale deployment of hydrogen that a key part of a future Swedish energy system. The lessons learned from these studies will also contribute knowledge that in many cases is also relevant to our Nordic neighboring countries.

Prof Simon Matti, Political Science, LTU
* Glossary
Policy: decided goals, strategies and approaches. Often political, but also found in other activities.
Policy landscape: the total amount of policies that exist within an area (and neighboring areas) at a given time.
Policy conflicts: when policies in the policy landscape express incompatible or countervailing goals and strategies, or involve the implementation of countervailing policies.
Coherence: agreement.
Coordination externalities: costs incurred when two or more actors try to coordinate their activities.
Significant reductions in safety distances for hydrogen installations
A key issue in the establishment of new hydrogen plants is how it can be placed in relation to the surroundings and what distances are required between different parts of the plant. The guidance on how this should be determined has been very limited, which has meant that the issue has been handled differently in different projects. Based on completed installations, it can be stated that this has led to different results and thus varying safety levels. Additionally, the permitting process has often been prolonged due to extensive dialogue between installers and rescue services.
Energigas Sweden's guidance for filling stations, H2-TSA, as well as MSB's planned rules for hydrogen plants can be expected to lead to more efficient and uniform management in the future. However, it has turned out that there is a lack of knowledge needed to be able to determine relevant distances, which has forced conservative assumptions on the part of the regulatory authorities, something that complicates and makes installation more expensive. For some applications, such as hydrogen pipelines, there is currently a complete lack of guidance. Even for large-scale installations, where H2-TSA does not provide any guidance, the situation is unclear. A recent compilation of research needs in hydrogen and battery safety (Runefors, 2024) highlights safety distances as the single most important area for future research, as identified by both researchers and stakeholders.
The research need that this work package intends to address is linked partly to conducting experiments to be able to meet the above knowledge needs and thus be able to reduce the safety distances for hydrogen plants while maintaining the safety level and to produce a knowledge base for applications where guidance on safety distances is currently lacking.
Particular focus is placed on scenarios relevant to hydrogen pipelines. One example is investigations of underground leakage of hydrogen gas to study how it is transported in the ground and whether there is a risk of accumulation under frost or building structures. Studies are also being conducted to study both radiation from hydrogen jet flames and delayed ignition of the released hydrogen, which can lead to a pressure wave. These studies, which are carried out as a combination of experiments and simulation/models development, constitute a central knowledge base for developing safety distances for hydrogen pipelines.
After extensive data analysis, we have finalized a new model to calculate the distance at which combustion products from a hydrogen jet flame begin to “turn upwards.” This turning point marks the transition from a momentum-driven jet to buoyancy-dominated flow (see Figure 1). The model allows for significant reductions in safety distances for hydrogen installations in accordance with, for example, the Swedish guideline H2-TSA and the upcoming national regulations. A scientific paper describing the experiments and model is currently under peer review and expected to be published in the coming months.

Figure 1 – Illustration of the part of the release that is dominated by inertia (momentum-driven jet) and buoyancy.
Underground Releases
A feasibility study on the experimental setup for underground hydrogen releases has been completed and submitted to the International Conference on Hydrogen Safety (ICHS) in September. This work has established sufficient experimental confidence to proceed with full-scale empirical studies. These will include:
- A comparative analysis of underground migration behaviors for hydrogen and methane
- Development of a validation dataset for model scaling from laboratory to real-world applications
Simulation of Pipeline Damage Scenarios
We are also conducting simulations of large hydrogen releases, based on a typical scenario where an excavator damages a hydrogen pipeline. This scenario is commonly used in, for example, Sweden and the UK to determine pipeline safety distances. The simulation model has been adapted to account for:
- Overpressure effects from delayed ignition
- Radiative heat transfer from hydrogen jet flames
Radiative Heat Transfer Studies
Finally, we are investigating radiative heat transfer from hydrogen jet flames to nearby objects. The effective absorptivity, the proportion of thermal radiation absorbed, has been measured for different industrial materials:
Sample | Effective absorptivity for H2 flames |
Blue power cable | 93 % |
Protective insulation cap | 84 % |
Protective aluminium cap | 13 % |
We are currently examining how air humidity between the flame and the object affects radiation attenuation and spectral distortion, which could have important implications for risk assessment and material selection in hydrogen environments.
This means that we can now perform calculations for hydrogen-specific flame behavior. Based on molecular physics, it is now possible to make precise predictions of thermal radiation from hydrogen jet flames and assess their effects on the surrounding environment.

Michael Försth, Professor LTU and Marcus Runefors, Associate professor, LTH presenting results at the Nordic Hydrogen Valley conference in Luleå, 23 January 2025
Public events where H2SIPP will be presented in near term
- 27-28 Aug: CH2ESS Researchers Day, Luleå (LTU CH2ESS Research Days 2025 | Luleå tekniska universitet
External link.)
- 22-26 Sept: International Conference on Hydrogen Safety, Seoul (International Conference on Hydrogen Safety — Hydrogen and Fuel Cell Safety
External link.)
- 24-25 Sept: Förebyggandekonferensen 2025, Karlstad (Förebyggandekonferensen 2025 | MSB
External link.)
Public events where H2SIPP was already presented
The Nordic Hydrogen Valleys Conference, 22-23 January 2025, Nordic hydrogen solutions for our shared future – Nordic Energy Research External link.
During the Nordic Hydrogen Valley Conference many of the barriers analysed in the ongoing research project Hydrogen Safety and Improved Permit Processes (H2SIPP) were discussed, such as safety distances, permit processes, and social and political acceptance and engagement, with the following main conclusions:
- The companies struggle with unclear regulations but find their ways.
- The public acceptance and commitment are tested, now that the first hydrogen pipelines are planned in northern Sweden.
- The first experiments within the project are performed, to improve the calculation models on safety distances.
Links to the three specific presentations from the conference, with outcomes from H2SIPP:
- Hydrogen Safety and Improved Permit Processes (H2SIPP)
External link., Cecilia Wallmark, Luleå University of Technology
- Progress in safety distance determination for hydrogen installations
External link., Marcus Runefors, Lund University, and Michael Försth, Luleå Technical University
- Actors’ views on regulations and permitting: Results from a survey
External link., Oskar Johansson, Luleå University of Technology
Public conversations on hydrogen from H2SIPP partners
- Michael Försth from LTU explains that his research focuses on improving safety in hydrogen infrastructure by studying two key areas: (1) how heat radiation from hydrogen flames affects people, vehicles, and buildings, and (2) how hydrogen explosions impact structures both internally and externally. Using advanced modeling and fundamental science, the goal is to create accurate safety guidelines that ensure protection without being overly conservative, enabling a cost-effective green transition. This video is available on YouTube
External link.
- Hydrogen: Shaping a Sustainable Future! The podcast Wattsup!
External link. where Cecilia Wallmark talks about the pivotal role of hydrogen in shaping the future energy market and on long term planning. Recorded on 5/12 2024.
Comment on hydrogen projects at Åland, for local radio by Cecilia Wallmark. Two online versions – 2 and 10 minutes, respectively: Vätgas - Ålands Radio & TV External link., 13/1 2025 (In Swedish)
Newly published related reports
For more information on hydrogen safety read Runefors, M. (2024), "Perceived research needs for Battery and Hydrogen Safety – A Nordic Perspective", Report 7057, Div. of Fire Safety Engineering, Lund University, Sweden External link.
At the Swedish Hydrogen Conference 2024, External link. Cecilia Wallmark, opened the conference by highlighting Sweden’s activities across the entire hydrogen value chain. The hydrogen safety group at LTU contributed with a poster showcasing their research on hydrogen jet fires and explosion impacts, part of the H2SIPP project. For more information, read
Connected education at LTU
Grundläggande vätgassäkerhet | Luleå tekniska universitet (ltu.se) External link.
Read more about the fire and explosion part of the research within H2SIPP at LTU: H2SIPP | Luleå tekniska universitet (ltu.se) External link.

Figure of the project consortia: Luleå tekniska universitet (LTU), Lunds universitet (LTH), Aalto Universitet (Aalto), Norges teknisk-naturvetenskapliga universitet (NTNU), Energigas Sverige, Zelk Energy, Skoogs Bränslen, Bodens Utveckling AB, Gällivares näringsliv, SSAB, Gen-H Oy, Hydri, Nordion Energi, AFRY.
Financiers: Nordic Energy Research with the program Nordic Hydrogen Valleys as Energy Hubs, funded by the Swedish Energy Agency, Business Finland, and Innovation Norway.
Contact
Cecilia Wallmark
- Director, Centre for Hydrogen Energy Systems Sweden, CH2ESS
- 0920-492847
- cecilia.wallmark@ltu.se
- Cecilia Wallmark
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