Canadian hydrogen safety program

2015

The rapid evolution of information related to hydrogen safety is multidimensional ranging from developing codes and standards to CFD simulations and experimental studies of hydrogen releases to a variety of risk assessment approaches. This information needs to be transformed into system design, risk decision-making and first responder tools for use by hydrogen community stakeholders. The Canadian Transportation Fuel Cell Alliance (CTFCA) has developed HySTARtm, an interactive Hydrogen Safety, Training And Risk System. The HySTARtm user interacts with a Web-based 3-D graphical user interface to input hydrogen system configurations. The system includes a Codes and Standards Expert System that identifies the applicable codes and standards in a number of national jurisdictions that apply to the facility and its components. A Siting Compliance and Planning Expert System assesses compliance with clearance distance requirements in these jurisdictions. Incorporating the results of other CTF...

The rapid evolution of information related to hydrogen safety is multidimensional ranging from developing codes and standards to CFD simulations and experimental studies of hydrogen releases to a variety of risk assessment approaches. This information needs to be transformed into system design, risk decision-making and first responder tools for use by hydrogen community stakeholders. The Canadian Transportation Fuel Cell Alliance (CTFCA) has developed HySTARtm, an interactive Hydrogen Safety, Training And Risk System. The HySTARtm user interacts with a Web-based 3-D graphical user interface to input hydrogen system configurations. The system includes a Codes and Standards Expert System that identifies the applicable codes and standards in a number of national jurisdictions that apply to the facility and its components. A Siting Compliance and Planning Expert System assesses compliance with clearance distance requirements in these jurisdictions. Incorporating the results of other CTF...

International Journal of Hydrogen Energy, 2009

The permitting process for hydrogen fueling stations varies from country to country. However, a common step in the permitting process is the demonstration that the proposed fueling station meets certain safety requirements. Currently, many permitting authorities rely on compliance with wellknown codes and standards as a means to permit a facility. Current codes and standards for hydrogen facilities require certain safety features, specify equipment made of material suitable for hydrogen environment, and include separation or safety distances. Thus, compliance with the code and standard requirements is widely accepted as evidence of a safe design. However, to ensure that a hydrogen facility is indeed safe, the code and standard requirements should be identified using a risk-informed process that utilizes an acceptable level of risk. When compliance with one or more code or standard requirements is not possible, a n evaluation of the risk associated with the exemptions to the requirements should be understood and conveyed to the Authority Having Jurisdiction (AHJ). Establishment of a consistent risk assessment toolset and associated data is essential to performing these risk evaluations. This paper describes an approach for risk-informing the permitting process for hydrogen fueling stations that relies primarily on the establishment of risk-informed codes and standards. The proposed risk-informed process begins with the establishment of acceptable risk criteria associated with the operation of hydrogen fueling stations. Using accepted Quantitative Risk Assessment (QRA) techniques and the established risk criteria, the minimum code and standard requirements necessary to ensure the safe operation of hydrogen facilities can be identified. Riskinformed permitting processes exist in some countries and are being developed in others. To facilitate consistent risk-informed approaches, the participants in the International Energy Agency (IEA) Task 19 on hydrogen safety are working to identify acceptable risk criteria, QRA models, and supporting data 1 . 1 This work is being conducted as part of Task 19 -Hydrogen Safety, a collaboration of experts from eight countries, under the Hydrogen Implementing Agreement of the International Energy Agency which operates under an international agreement of more than 26 countries. The overall goal of the IEA task on hydrogen safety is to develop data and other information that will facilitate the accelerated adoption of hydrogen systems and supports the accomplishment of the Hydrogen Implementing Agreement's stated mission: "…to accelerate hydrogen implementation and widespread utilization." Because of the nature of the International Energy Agency as an international agreement between governments, it is hoped that such collaboration will complement other efforts to build the technology base around which codes and standards can be developed.

For large-scale distribution and use of energy carriers classified as hazardous material in many countries as a method to assist land use planning, to grant licenses, to design a safe installation and to operate it safely some form of risk analysis and assessment is applied. Despite many years of experience the methods have still their weaknesses even the most elaborated ones as e.g. shown by the large spread in results when different teams perform an analysis on a same plant as was done in EU projects. Because a fuel as hydrogen with its different properties will come new in the daily use of many people incidents may happen and risks will be discussed. HySafe and other groups take good preparatory action in this respect and work in the right direction as appears from various documents produced. However, already a superficial examination of the results so far tells that further cooperative work is indispensable. To avoid criticism, skepticism and frustration not only the positive findings should be described and general features of the methods but the community has also to give strong guidance with regard to the uncertainties. Scenario development appears to be very dependent on insight and experience of an individual analyst, leak and ignition probability may vary over a wide range of values, Computational Fluid Dynamics, or CFD models may lead to very different result. The Standard Benchmark Exercise Problems, SBEPs, are a good start but shall produce guidelines or recommendations for CFD use or even perhaps certification of models. Where feasible narrowing of possible details of scenarios to the more probable ones taking into account historical incident data and schematizing in bowties, more explicit use of confidence intervals on e.g. failure rates and ignition probability estimates will help. Further knowledge gaps should be defined.

The paper describes the development of risk acceptance criteria and risk assessment methodology for early phase introduction of hydrogen (H 2) applications. Hydrogen refuelling stations for hydrogen fuelled vehicles were used as case studies. This was done as a task in the European Commission funded research project European Integrated Hydrogen Project phase 2 (EIHP2). The EIHP2 shall provide input to regulatory activities on a European Union and global level facilitating the safe development, introduction and daily operation of hydrogen fuelled vehicles on public roads and their refilling at public hydrogen refuelling stations. The suitability of a risk based approach to development of standards and regulations is discussed. Risk acceptance criteria are an important part of safety management and reflect the targeted safety level. Criteria must be established before conducting risk assessments to enable comparison against the desired safety level. Risk acceptance criteria based on general societal risk were developed, and the resulting risk acceptance criteria are described in detail. Early phase introduction of hydrogen applications in the public domain is characterised by the lack of relevant, detailed technical information and historical incident and accident data. A method for risk assessments was developed to take into account hydrogen specific issues and early concept phase. The risk assessment methodology was then used for risk assessments of different concepts for hydrogen refuelling stations. The conclusion discusses the suitability of the risk acceptance criteria and the risk assessment methodology based on experiences from the case studies. Keys to success are also presented. Acknowledgement: The authors thank the European Commission for partial funding through the EIHP2 project under contract: ENK6-CT2000-00442, and DNV and Norsk Hydro ASA for kind support and financial contributions.

Nuclear Engineering and Technology, 2015

During the course of a severe accident in a light water nuclear reactor, large amounts of hydrogen can be generated and released into the containment during reactor core degradation. Additional burnable gases [hydrogen (H 2) and carbon monoxide (CO)] may be released into the containment in the corium/concrete interaction. This could subsequently raise a combustion hazard. As the Fukushima accidents revealed, hydrogen combustion can cause high pressure spikes that could challenge the reactor buildings and lead to failure of the surrounding buildings. To prevent the gas explosion hazard, most mitigation strategies adopted by European countries are based on the implementation of passive autocatalytic recombiners (PARs). Studies of representative accident sequences indicate that, despite the installation of PARs, it is difficult to prevent at all times and locations, the formation of a combustible mixture that potentially leads to local flame acceleration. Complementary research and development (R&D) projects were recently launched to understand better the phenomena associated with the combustion hazard and to address the issues highlighted after the Fukushima Daiichi events such as explosion hazard in the venting system and the potential flammable mixture migration into spaces beyond the primary containment. The expected results will be used to improve the modeling tools and methodology for hydrogen risk assessment and severe accident management guidelines. The present paper aims to present the methodology adopted by Institut de Radioprotection et de Sû ret e Nucl eaire to assess hydrogen risk in nuclear power plants, in particular French nuclear power plants, the open issues, and the ongoing R&D programs related to hydrogen distribution, mitigation, and combustion.

2011

The report describes the findings of a workshop that was held at the Institute for Energy and Transport (JRC) in Petten Netherlands, on the topic “Gap analysis of CFD modelling of hydrogen release and combustion”. The main topic was divided in 6 sub-topics: release and dispersion,auto-ignition, fires, deflagrations, detonations and DDT, and accident consequences. For each sub-topic, the main gaps in CFD modelling were identified and prioritised.Hydrogen is expected to play an important role in the energy mix of a future low carbon society, (the European Strategic Energy Technology Plan of the European Commission (COM 2007 - 723) and in the Hydrogen, Fuel Cells & Infrastructure Technologies Program-Multi-Year Research, Development, and Demonstration Plan of the USA Department of Energy (DoE 2007).Hydrogen safety issues must be addressed in order to ensure that the wide spread deployment and use of hydrogen and fuel cell technologies can occur with the same or lower level of hazardsan...

Within the framework of the internal project HyQRA of the HYSAFE NoE, funded by EC, the participating partners were requested to apply their quantitative risk assessment (QRA) methodologies on an agreed predefined hypothetical gaseous hydrogen fueling station, the BBC station (Benchmark Base Case). The overall aim of the HyQRA was to perform an inter-comparison of the various QRA approaches and identify any knowledge gaps on data and information used in the QRA steps specifically related to hydrogen. Within this internal project, partners NCSRD and UNIPI collaborated on a common QRA. UNIPI identified the hazards on site, selected the most critical ones, defined the events that could be the primary cause of an accident and provided to NCSRD the scenarios listed in risk order for the evaluation of the consequences. NCSRD performed the quantitative analysis using the ADREA-HF CFD code. The predicted spatial and transient evolution of the formed flammable hydrogen-air clouds in the realistic geometry were provided to UNIPI for analysis of the consequences and evaluation of the risk and distances of damage to suggest improvements in the design and management of the BBC station to reduce the risk. In total fifteen scenarios were simulated. The first five were hydrogen releases in confined ventilated environment. Three scenarios concerned leaks inside the compression building, a small leak, a large leak and a pipeline rupture (initial flow rates 0.0114 kg/s, 0.0456 kg/s and 1.14 kg/s respectively), under 150 ACH mechanical ventilation conditions. Two scenarios concerned leaks inside the purification/drying building, a small leak and a pipeline rupture (initial flow rates 0.000138 kg/s and 0.0312 kg/s), under 150 ACH mechanical ventilation as well. The remaining ten scenarios were releases in open/semi-confined environment. Four scenarios concerned the storage cabinet, a small leak and a pipeline rupture (initial flow rates 0.0118 kg/s and 1.18 kg/s), under two ambient wind speed conditions (1.5 and 5 m/s). Four scenarios concerned the storage bank, a leak from one cylinder and a leak fed from the storage bank (0.0472 kg/s initial flow rates in both cases), at two wind speed conditions as above. Finally, the last two scenarios concern a large leak (0.0472 kg/s initial flow rate) from the refueling hose of one dispenser, at two wind speed conditions, as above. This paper presents the CFD methodology applied and discusses the results obtained from the performed calculations. 1 INTRODUCTION Research into hydrogen energy and technology applications is part of the overall efforts to address the challenges of climate change, air pollution and energy independence. Specifically, the hydrogen fuel vehicles are considered to offer many benefits such as zero emissions and improved overall efficiency. Going one step further, the supporting fueling infrastructure is an essential component to the successful adoption of future hydrogen vehicles. Currently, 173 hydrogen fueling stations exist worldwide [1]. Most of them were built for demonstration and testing purposes whereas a few are open to the public. 58 stations are planned to be built in the near future [1]. However, before hydrogen fueling stations become a commonplace in the market, issues such as storage technology, containment, delivery and most of all safety requirements need to be addressed.

International Journal of Hydrogen Energy, 2017

Hydrogen fuels are being deployed around the world as an alternative to traditional petrol and battery technologies. As with all fuels, regulations, codes and standards are a necessary component of the safe deployment of hydrogen technologies. There has been a focused effort in the international hydrogen community to develop codes and standards based on strong scientific principles to accommodate the relatively rapid deployment of hydrogen-energy systems. The need for science-based codes and standards has revealed the need to advance our scientific understanding of hydrogen in engineering environments. This brief review describes research and development activities with emphasis on scientific advances that have aided the advancement of hydrogen regulations, codes and standards for hydrogen technologies in four key areas: (1) the physics of high-pressure hydrogen releases (called hydrogen behavior); (2) quantitative risk assessment; (3) hydrogen compatibility of materials; and (4) hydrogen fuel quality.