FEBRUARY 2025 2025/142 A KNOWLEDGE NOTE SERIES FOR THE ENERGY & EXTRACTIVES GLOBAL PRACTICE Safety aspects of hydrogen and its main derivatives: A literature review for policy makers The bottom line. This Live Wire focuses on safety concerns associated with hydrogen and its main derivatives: ammonia and methanol. After an exhaustive review of the literature and measures on hydrogen safety, the study summarized here found robust, well-established standards developed by reputable institutions. This brief emphasizes the critical importance of adhering to these standards and encourages their full implementation to ensure effective and consistent safety practices. In a word… Since hydrogen is not found in its free form in nature, it must be produced. Clean hydrogen—produced from renewable Hydrogen is the simplest and most abundant element energy sources and fossil fuels with responsible carbon cap- in the universe ture and storage—can play an important role in the global Since its discovery almost 250 years ago by Henry Cavendish energy transition, accelerating progress toward global cli- and Antoine Lavoisier, hydrogen has been seen as a tool of mate goals. progress. Currently, hydrogen is used in many different appli- cations, but not directly; instead, most applications use its As an energy carrier, hydrogen can be used to store, move, two main derivatives, ammonia and methanol. and deliver energy. Derivative chemical products with high added value, such as ammonia or methanol, can also be Hydrogen produced from renewable sources can provide obtained from hydrogen. These derivatives enable efficient environmentally clean, affordable, and secure fuel for storage and transport of hydrogen, making them crucial electricity generation, transportation, and other sectors components in the shift toward sustainable energy systems. (Tchouvelev 2016). While it holds immense potential to rev- By leveraging these technologies, industries can reduce their olutionize the energy sector, it also presents unique safety carbon footprint and contribute to a more sustainable future. challenges that must be addressed to ensure it is produced, stored, and utilized safely (DOE 2016). Widespread adoption The deployment of clean hydrogen is particularly important of hydrogen requires understanding its properties and the for decarbonizing hard-to-abate sectors, such as steel pro- associated safety concerns. duction and long-haul transportation. But as global efforts to develop clean hydrogen intensify, it is essential to guaran- tee that risks are managed effectively. Author Carmen Conde Pardavila is an energy analyst with the Energy Sector Management Assistance Program at the World Bank 2 Safety aspects of hydrogen and its main derivatives: A literature review for policy makers This brief offers an overview of the main risks associated with The storage and handling of hydrogen thus poses significant hydrogen and its primary derivatives, ammonia and meth- challenges. Hydrogen can be stored either as a compressed anol. It aims to enhance policy makers’ understanding of gas or in a cryogenic liquid state. Compressed hydrogen hydrogen safety and promote the development of safe and storage requires high-pressure systems that can withstand sustainable hydrogen policies. To this end, it synthesizes cur- pressures up to 700 bars. Alternatively, storing hydrogen as rent research, identifies potential risks, and offers actionable a liquid necessitates extremely low temperatures, below recommendations to ensure the safe and efficient integra- –253°C, demanding advanced insulation and careful han- tion of hydrogen technologies. International best practices dling to prevent boil-off and leaks. Both storage methods will not be addressed since there are no clear global leaders require robust containment solutions to minimize the risk of in hydrogen safety. leaks and ensure safety (Calabrese et al. 2024). Let’s start with hydrogen, before moving Another crucial issue is material compatibility. Hydrogen on to ammonia and methanol. What are its has the potential to cause embrittlement in certain met- chief properties and safety concerns? als, which can lead to the failure of pipelines and of tanks and other storage vessels. Special materials and protective Safe utilization of hydrogen requires meticulous coatings are required to maintain the integrity of hydrogen management of the safety challenges presented by its storage and transport systems (Calabrese et al. 2024). unique properties Hydrogen is a colorless, odorless, and highly flammable gas Finally, the detection and monitoring of hydrogen leaks under standard conditions. It is the lightest element, with a present their own set of challenges. Given that hydrogen is molecular weight of just 2.02 grams per mole. Hydrogen’s both odorless and colorless, detecting leaks without special- wide flammability range in air (4–75 percent by volume), low ized sensors can be exceedingly difficult. Reliable hydrogen ignition energy (0.02 millijoules [mJ]), and high diffusivity detection systems must therefore be implemented at the mean that it can easily spread in and mix with air. In addi- outset of any project to detect leaks early and prevent haz- tion, hydrogen burns with an almost invisible flame, posing ardous situations. challenges for detection and firefighting (DOE 2016). Fully realizing hydrogen’s potential as a clean energy source, Among the primary concerns is hydrogen’s explosiveness. while ensuring the safety of people and infrastructure, Even minor leaks can quickly result in the formation of explo- requires addressing these safety concerns using rigorous sive mixtures with air, highlighting the critical need for strin- controls, safety protocols, and continuous monitoring. gent leak detection and effective ventilation measures (DNV 2021). Hydrogen is no more or less dangerous than other flam- mable fuels, including gasoline and natural gas. The safety concerns surrounding hydrogen are not a cause for alarm, “Clean hydrogen—produced from renewable but are simply different from the customary concerns sur- rounding gasoline or natural gas. In fact, some of hydrogen’s energy sources and fossil fuels with particularities actually provide safety benefits compared responsible carbon capture and storage—can with gasoline or other fuels. Some of the most notable differ- ences are listed below (NHA 2010). play an important role in the global energy transition, accelerating progress toward Hydrogen is lighter than air and diffuses rapidly. Hydrogen has high diffusivity (3.8 times faster than that of natural gas); global climate goals.” this means that, when released, it dilutes quickly into a non- flammable concentration. Hydrogen rises twice as fast as helium and six times faster than natural gas—at a speed of Safety aspects of hydrogen and its main derivatives: A literature review for policy makers 3 almost 45 miles per hour (20 m/s). Therefore, unless a roof, “To become a fire hazard, hydrogen must a poorly ventilated room, or some other structure contains the rising gas, the laws of physics prevent hydrogen from first be confined—but confining the lightest lingering near a leak (or near people using hydrogen-fueled element in the universe is very difficult.” equipment). Simply stated, to become a fire hazard, hydro- gen must first be confined—but confining the lightest ele- ment in the universe is very difficult. Engineers consider these Combustion. Like any flammable fuel, hydrogen can com- properties when designing structures where hydrogen will be bust. However, its buoyancy, diffusivity, and small molecular used. Their designs help hydrogen escape up and away from size make it difficult to contain, so a situation where it might users in case of an unexpected release. combust is hard to create. An adequate concentration of hydrogen, an ignition source, and the right amount of oxi- Hydrogen is odorless, colorless, and tasteless, so most dizer (like oxygen) must all be present at the same time for human senses will not help detect a leak. For that and other a hydrogen fire to occur. Hydrogen has a wide flammability reasons, the industry often uses hydrogen sensors to help range (4–75 percent in air) and might require quite a low detect leaks and has maintained a high safety record using amount of energy to ignite (0.02 mJ). However, the energy these for decades. By comparison, natural gas is also odorless, required to ignite it is high at low concentrations (below 10 colorless, and tasteless, but the industry adds a sulfur-con- percent)—similar to the energy required to ignite natural gas taining odorant, called mercaptan, to make it detectable by and gasoline in their respective flammability ranges—mak- smell. However, all known odorants contaminate fuel cells (a ing hydrogen realistically more difficult to ignite near the popular application for hydrogen). Researchers are investi- lower flammability limit. On the other hand, if conditions gating other possible hydrogen detection methods: tracers, allow an increase of hydrogen’s concentration toward the new odorant technologies, advanced sensors, and others. stoichiometric (most easily ignited) mixture of 29 percent (in air), then the ignition energy drops to about one-fifteenth of Hydrogen flames have low radiant heat. Hydrogen com- that required to ignite natural gas (or one-tenth for gasoline). bustion primarily produces heat and water. Since it produces Table 1 summarizes the main properties of widely used fuels. not carbon but a heat-absorbing water vapor, a hydrogen fire has significantly less radiant heat than a hydrocarbon Explosion. An explosion cannot occur in a tank or any con- fire. The heat released near a hydrogen flame is low (though tainment that stores only hydrogen. An explosion requires an the flame itself is just as hot), meaning that the risk of sec- oxidizer in a specific concentration (e.g., pure oxygen in a ondary fires is also low. This fact has significant implications concentration of at least 10 percent or air in a concentration for the public and for rescue workers. of 41 percent). Hydrogen can be explosive at concentra- tions of 18.3–59 percent. While this range is wide, it is worth Table 1. Comparison of the properties of widely used fuels Hydrogen Ammonia Gasoline vapor Natural gas Flammability limits (in air) 4–75% 15–28% 1.4–7.6% 5.3–15% Explosion limits (in air) 18.3–59.0% 15–28% 1.1–3.3% 5.7–14% Ignition energy (millijoules) 0.02 0.2 0.20 0.29 Flame temperature in air (ºC) 2,045 1,800 2,197 1,875 Stoichiometric mixture (most easily ignited in air) 29% 15% 2% 9% Source: Original compilation based on NHA (2010), New Jersey Department of Health (2016), National Institute for Occupational Safety and Health (2024), and Kobayashi et al. (2018). 4 Safety aspects of hydrogen and its main derivatives: A literature review for policy makers remembering that gasoline can be more hazardous, since it can explode at much lower concentrations (1.1–3.3 per- hydrogen ultra-cold uses double-walled, vacuum-jacketed, cent). Further, there is very little likelihood that hydrogen will superinsulated liquid hydrogen storage containers that are explode in open air, because of its tendency to rise quickly. designed to vent hydrogen safely in gaseous form if a breach This is the opposite of heavier gases such as propane or gas- of either the outer or the inner wall is detected. These robust oline fumes, which hover near the ground, creating a greater construction and redundant safety features dramatically explosion risk. reduce the likelihood of human contact. For more information on hydrogen’s properties and main safety concerns, the following sources may be consulted: “Occasional explosions at hydrogen refueling stations contribute to the public’s perception 3 “Properties and Effects of Hydrogen” (EIGA 2019, chapter 4) of hydrogen as unsafe, though the explosion 3 “Hydrogen Has Unique Physical Properties Making It risk is not greater than for other gases.” Significantly More Reactive When Compared to Methane” (Accufacts Inc. 2022, chapter 4) 3 Hydrogen Technologies Safety Guide (NREL 2015) The need for an oxidizer for a hydrogen explosion means the explosion risk is lower than commonly perceived. It neverthe- 3 “Safety Aspects of Green Hydrogen Production on less remains a safety concern that needs to be addressed. Industrial Scale” (ISPT 2023) Occasional explosions at hydrogen refueling stations, for example, in Germany in June 2024 or in Norway in January 3 “Hydrogen Safety Challenges: A Comprehensive Review 2024 (Electrive 2024), contribute to the public’s perception of on Production, Storage, Transport, Utilization, and CFD- hydrogen as unsafe, though the explosion risk is not greater Based Consequence and Risk Assessment” (Calabrese than for other gases. But since hydrogen is a relatively new et al. 2024) industry, these incidents create significant public aversion. Implementing more security measures and disseminating 3 The Hydrogen Incident and Accidents Database- HIAD 2.1 risk assessments—for example, the “Hydrogen Leakage Risk (European Commission 2023c) Assessment for Hydrogen Refueling Stations,” published in the International Journal of Hydrogen Energy in 2023—could 3 “Hydrogen: How to Meet the Safety Challenges” (Dräger help improve hydrogen’s image (Wang and Gao 2023). 2020) Asphyxiation. All gases except oxygen can cause asphyx- 3 “Regulatory Framework, Safety Aspects, and Social iation. However, hydrogen’s buoyancy and diffusivity mean Acceptance of Hydrogen Energy Technologies,” chapter 6 that in most scenarios, it is unlikely to be confined sufficiently of Science and Engineering of Hydrogen-Based Energy for asphyxiation. Technologies (Tchouvelev, de Oliveira, and Neves 2018) Toxicity/poison. Hydrogen is nontoxic and nonpoisonous. It 3 The Center for Hydrogen Safety (CHS 2024), a global non- will not contaminate groundwater (it is a gas under normal profit founded in 2019 to provide guidance, education, atmospheric conditions), nor will its release pollute the envi- and collaborative forums on hydrogen safety and global ronment. Hydrogen does not create “fumes.” best practices Cryogenic burns. Any cryogenic liquid (hydrogen becomes 3 Hydrogen Safety Review (NETL 2023) a liquid below -423°F) can cause severe freeze burns upon contact with skin. However, the current method to keep 3 Fundamentals of Hydrogen Safety Engineering II (Molkov 2012). Safety aspects of hydrogen and its main derivatives: A literature review for policy makers 5 Apart from the above references, the European Commission directed toward fertilizers, while 18 percent is used in indus- Joint Research Centre, through the Major Accidents trial processes, and a small percentage is used in refrigera- Hazards Bureau and in particular the Minerva Portal, tion and air-conditioning systems. organized a two-part webinar on hydrogen risks—the first part in September 2023 and the second in February 2024 (European Commission 2023a, 2024). It was a comprehen- “Ammonia toxicity poses a particular threat sive webinar; many countries participated (e.g., Germany, to aquatic habitats in coral reefs, polar the Netherlands, Japan, Finland, France, and the United Kingdom). Participants discussed the most relevant safety regions, and mangroves, with potential issues in the industry, revealing different concerns at the implications for food chain dynamics. national and international levels. For the purpose of this Live Wire, a European Commission document outlining relevant Effective spill management is crucial to reliable hydrogen safety resources is particularly noteworthy prevent contamination and protect aquatic (European Commission 2023b). environments.” Development institutions such as the Inter-American Development Bank (IDB) have conducted studies on green hydrogen’s safety. “Environmental, Health, Safety, and Social The Haber-Bosch process is often considered to have high Management of Green Hydrogen in Latin America and the energy and cost requirements, but the vast majority of the Caribbean” was published in May 2023. energy inputs, carbon dioxide emissions, capital, and opera- tional costs are actually related to hydrogen production; the Moving on to ammonia, what are its chief synthesis of ammonia from hydrogen requires relatively small safety challenges? additional effort and investment. Although no more or less dangerous than other fuels, Many low-emission ammonia plants are now under develop- ammonia’s safety profile is distinct ment or have recently become operational, demonstrating Ammonia (NH₃) is a clear, colorless gas with a pungent odor the technical feasibility of decarbonizing ammonia produc- at room temperature and under atmospheric pressure. Under tion. Low-emission ammonia plants constituting over 22.5 normal conditions, it is highly soluble in water and forms a million tons of capacity are likely to become operational in solution known as ammonium hydroxide (NH₄OH), which is 2030; more than 293.3 million tons are under development a weak base. For industrial purposes, ammonia is typically (Ammonia Energy Association 2024b). pressurized and cooled to be stored and transported as a liquid to increase efficiency and safety. Ammonia is no more or less dangerous than other fuels, including hydrogen, gasoline, and natural gas. Its safety Ammonia is typically produced via the Haber-Bosch process, profile is quite different, however, with toxicity and causticity a high-temperature and high-pressure catalytic reaction replacing flammability. As with hydrogen, the safety con- between nitrogen (N₂) and hydrogen (H₂): cerns surrounding ammonia are not a cause for alarm as N2(g)+3H2(g) ⇌ 2NH3(g) they are already well known and well managed in existing sectors (refrigeration, chemicals, agriculture), but knowledge transfer is critical to ensure that other sectors adopt ammo- This process is one of the largest industrial uses of fossil fuels nia safely. A very important future use of green ammonia will and contributes approximately 1 percent of global carbon be as a shipping fuel. emissions. However, ammonia has an indispensable role in agriculture, where it is used to produce fertilizers such Some of the most notable risks related to ammonia are as as urea, ammonium nitrate, and ammonium sulfate. The follows. vast majority of ammonia produced (about 80 percent) is 6 Safety aspects of hydrogen and its main derivatives: A literature review for policy makers Exposure risk. Exposure to ammonia can be hazardous Storage and handling. Given its hazards, ammonia must due to its corrosive properties and causticity. Ammonia can be stored and handled following stringent safety protocols. corrode metals such as copper, brass, zinc, and some alloys, Storage tanks must be made of materials that can resist causing structural failures in equipment and containment ammonia’s corrosive effects. These tanks are often equipped systems. This poses risks to industrial infrastructure and can with safety features such as pressure release valves, and lead to leaks or spills, which may cause further hazards. they must be inspected regularly for leaks or structural weaknesses. Causticity specifically relates to ammonia’s immediate harmful impact on living organisms through direct contact— If a leak occurs, ammonia can spread rapidly and must be unlike toxicity, which involves longer-term systemic effects. contained and evacuated immediately. Facilities handling Ammonia is highly alkaline and can cause severe damage ammonia in large quantities are often required to have to skin, eyes, and mucous membranes upon direct contact. emergency response plans, including ammonia detection Inhalation of ammonia vapors can lead to respiratory tract systems, personal protective equipment for workers, and irritation, swelling, or even permanent damage, depend- access to medical facilities. ing on concentration levels. To mitigate this risk, the US Occupational Safety and Health Administration has set the The following are some useful resources on the safety of permissible exposure limit for ammonia at 50 parts per mil- ammonia: lion (ppm) over an eight-hour workday, and the short-term exposure limit is 35 ppm for 15 minutes. 3 “Safety Assessment of Ammonia as a Transport Fuel” (Risø National Laboratory 2005) Toxicity. Toxicity refers to the potential harmful effects of substances on aquatic life. When a spill occurs, toxic mate- 3 “Hydrogen and Ammonia Infrastructure: Safety and Risk rials can infiltrate water bodies, causing severe ecological Information and Guidance” (Lloyd’s Register 2020) damage. Prolonged exposure can disrupt marine ecosys- tems, poisoning fish, plants, and microorganisms. According 3 “Review of Global Regulations for Anhydrous Ammonia to the Environmental Defense Fund’s 2022 report” Ammonia Production, Use, and Storage” (Institution of Chemical at Sea: Studying the Potential Impact of Ammonia as a Engineers 2016) Shipping Fuel on Marine Ecosystems,” toxicity poses a par- ticular threat to aquatic habitats in coral reefs, polar regions, 3 “Ammonia Safety Study” (Zero Carbon Shipping 2022) and mangroves, with potential implications for food chain dynamics. Effective spill management is crucial to prevent 3 Ammonia Safety in Ammonia Plants and Related Facilities contamination and protect aquatic environments. This Symposium, an annual event, organized by the American includes stringent protocols for handling and containment, Institute of Chemical Engineers since 1955. and emergency response measures to minimize toxic expo- sure and mitigate long-term environmental impacts. Further, numerous organizations maintain ammonia safety standards; examples include the International Institute of Flammability and explosive potential. Ammonia is clas- All-Natural Refrigeration, a global organization dedicated sified as a flammable gas, despite its narrow flammability to promoting the use of natural refrigerants in cooling and limits: from 15 percent to 28 percent by volume in air. When refrigeration systems. The institute provides resources, stan- mixed with air, especially at high concentrations, ammonia dards, and technical guidance to ensure the safe, efficient, can form explosive mixtures, posing significant risks in indus- and environmentally friendly use of natural refrigerants such trial settings. However, ammonia’s relatively high auto-igni- as ammonia and carbon dioxide in various applications. The tion temperature (651°C) makes accidental ignition less likely following standards cover the ammonia detection and alarm compared with more volatile fuels like methane or hydrogen. requirements in the IIAR Standards: Safety aspects of hydrogen and its main derivatives: A literature review for policy makers 7 3 ANSI/IIAR 2-2021 Standard for Design of Safety Closed- the tank (instead of on the side of the tank), and (2) a tertiary Circuit Ammonia Refrigeration Systems (IIAR 2019). concrete outer wall to minimize the effect of any external impact (Yara 2023). 3 ANSI/IIAR 6-2019 Standard for Inspection, Testing, and Maintenance of Closed-Circuit Ammonia Refrigeration System (IIAR 2021). “The transition to ammonia as a marine The Compressed Gas Association develops and maintains fuel will require significant investment standards related to the safe storage, handling, and trans- in infrastructure, including specialized portation of ammonia, particularly anhydrous ammonia used in industrial applications. These standards cover various bunkering facilities and retrofitting ships with aspects related to the use of ammonia (for example, equip- ammonia-compatible engines.” ment design, safety practices, and regulatory compliance); help ensure ammonia is used safely in industrial applica- tions; and minimize the risks associated with its toxicity and flammability. A main safety concern with using ammonia as a marine fuel revolves around its toxicity and the potential for leaks during Ammonia is gaining attention as a potential alterna- bunkering, storage, and on-board handling. A GCMD (2023) tive marine fuel owing to its carbon-free combustion and report on ammonia bunkering in Singapore emphasizes the relatively high energy density compared with other hydro- need for robust safety guidelines, including the development gen carriers. Several reports, including the Global Centre of double-walled bunkering lines and tanks to minimize the for Maritime Decarbonisation’s “Safety and Operational risk of leaks, the implementation of advanced ventilation Guidelines for Piloting Ammonia Bunkering in Singapore” and neutralization systems to prevent ammonia build-up, (GCMD 2023) and the European Maritime Safety Agency’s and efforts ensuring that all personnel involved in ammonia report “Potential of Ammonia as Fuel in Shipping” (EMSA handling are properly trained and equipped with suitable 2022), highlight ammonia’s potential as a shipping fuel, its personal protective equipment. benefits, and the regulatory framework supporting its adop- tion. They highlight the safety challenges and the need for The transition to ammonia as a marine fuel will require further technological and regulatory advancements to sup- significant investment in infrastructure, including special- port its widespread use. ized bunkering facilities and retrofitting ships with ammo- nia-compatible engines. It will also require establishing a Several other organizations are also working on reports or comprehensive regulatory framework that addresses safety, tools regarding the use of ammonia as a fuel. For instance, environmental impact, and operational protocols. The indus- the Clean Marine Fuels Working Group within the World Ports try has progressed beyond research and pilot projects, and Sustainability Program has signed a memorandum of under- some ammonia vessels are under construction (e.g., a vessel standing with the Society of Gas as a Marine Fuel to develop being constructed by NYK, IHI, Japan Engine Corporation safety tools for ammonia as a fuel (WPSP 2024). and Nihon Shipyard, due for delivery in November 2026). Established ammonia safety measures are thus of the utmost The Netherlands updated its PGS-12 guidelines for ammo- importance (Ammonia Energy Association 2024a). nia storage and handling, preparing for increased ammo- nia imports to the country (Ammonia Energy Association Ammonia is a critical industrial chemical that offers signifi- 2024d). (The DCMR (the Dutch environmental protection cant benefits but also presents inherent risks. Its expanding agency) has permitted OCI Global to build a 60,000-ton role as a marine fuel brings new safety challenges that must ammonia storage tank in Rotterdam.) Some key changes for be addressed through rigorous safety standards, techno- the PGS-12 code in the Netherlands include (1) submerged logical innovation, and international collaboration. With the pumps for ammonia loading and unloading over the top of global shift toward decarbonization, ammonia’s role both as 8 Safety aspects of hydrogen and its main derivatives: A literature review for policy makers a key agricultural input and a potential clean fuel highlights which is subsequently processed to methanol. An emerging the importance of managing these risks effectively. method is direct synthesis from carbon dioxide and hydro- gen, which involves the catalytic hydrogenation of carbon Some useful resources on the safe use of ammonia as a bun- dioxide. kering fuel are listed below. 3 “Commercialising Early Ammonia-Powered Vessels” “Methanol’s ability to dissolve in water means (Global Maritime Forum 2023) that contamination of groundwater and soil is 3 “Ammonia at Sea: Studying the Potential Impact of a real risk, especially if containment measures Ammonia as a Shipping Fuel on Marine Ecosystems” are inadequate. These risks demand careful (Environmental Defense Fund 2022) monitoring, as even short-term exposure to 3 “Ammonia Powered Bulk Carrier” (Green Shipping Program high concentrations can have harmful effects 2023) on biodiversity.” 3 “External Safety Study—Bunkering of Alternative Marine Fuels for Seagoing Vessels” (DNV 2021) Among methanol’s various applications is its use as a chem- 3 “Final publication of International Maritime Organization ical feedstock in the production of formaldehyde, acetic (IMO) Guidelines for Ammonia as a Fuel in Q4 2024.” acid, and a variety of other chemicals. It also serves as a fuel These guidelines are expected to be adopted at the for internal combustion engines, used either directly or as a December 2024 Maritime Safety Committee meeting component of blended fuels, for example, M85, which is 85 (Ammonia Energy Association 2024c) percent methanol. Methanol is also used as a solvent in lab- oratories and industrial processes. It is also used in windshield 3 “Fuel for Thought: Ammonia Report” (Lloyd’s Register washer fluid and other antifreeze applications. Methanol 2024). can also be used as an energy carrier in fuel cells for the production of electricity. Its use in maritime transportation is Where does methanol fit in? becoming more common. Methanol is a versatile chemical with numerous The DNV (2021) report “External Safety Study—Bunkering of applications. Its principal safety concern is its toxicity Alternative Marine Fuel for Seagoing Vessels,” mentioned Methanol, also known as methyl alcohol, wood spirit, or above, also considers methanol’s safety concerns as a bun- wood alcohol, is a light, volatile, colorless liquid alcohol at kering fuel. Methanol is becoming an increasingly attractive room temperature and under atmospheric pressure. With a option for reaching global climate goals, as discussed in The distinctive odor, it is the simplest alcohol and can be trans- Maritime Executive article “Putting Methanol through Its ported readily. It is widely used in industrial processes, includ- ‘Paces,’ with a Focus on Safety” (2024). However, safety con- ing fuel production and chemical manufacturing. cerns regarding the adoption of methanol as a new fuel also need to be addressed. The Maritime Energy and Sustainable Methanol can be produced by several methods. The most Development Centre of Excellence, in collaboration with the common industrial method is natural gas reforming, which Methanol Institute, has carried out a more in-depth analysis involves the steam reforming of natural gas to produce in the report “Methanol as a Marine Fuel”(MESD Centre of synthesis gas (a mixture of hydrogen, carbon monoxide, Excellence and Methanol Institute 2021). and carbon dioxide), which is then converted to methanol. Another method is biomass gasification, where biomass is The main safety concern regarding methanol is its toxic- used as a feedstock and gasification produces synthesis gas, ity, for which its degradation products, formaldehyde and Safety aspects of hydrogen and its main derivatives: A literature review for policy makers 9 formate, are responsible. Methanol is highly toxic if ingested, impacts requires regulatory compliance in its transportation inhaled, or absorbed through the skin. Ingestion of more than and storage, coupled with stringent environmental pro- 20 milliliters can be lethal, while lesser quantities are known tection protocols. Ensuring quick response measures and to cause irreversible blindness. Methanol’s metabolism and remediation plans in case of spills is also critical to protecting toxicity are similar to those of ethylene glycol. Methanol nearby ecosystems (Methanol Institute 2020). must be handled and dispensed taking adequate precau- tions (IRENA and Methanol Institute 2021). Methanol also poses corrosion risks as it can degrade metals, rubber, and certain plastics over time, and can compromise Exposure to even small quantities of methanol must be the integrity of storage tanks, pipelines, and transport con- followed by immediate medical intervention, making it tainers. Methanol can corrode stainless steel, for instance, vital for industries handling methanol to have appropriate particularly under conditions of water contamination, which emergency response procedures in place. It is also important accelerates the process. This degradation not only increases to consider chronic, low-level exposure, which poses a signif- the likelihood of leaks and accidental releases but also icant concern for workers handling methanol over extended raises maintenance costs for industries handling methanol. periods. Even small but prolonged exposure to methanol Industries must use containers made from resistant mate- can lead to cumulative health impacts, such as headaches, rials, such as specific alloys or treated plastics, and regu- vision impairment, and neurological symptoms (Methanol larly inspect and maintain infrastructure to prevent failure. Institute 2020; US Environmental Protection Agency 2016). Risks can be reduced further by adding corrosion inhibitors to methanol storage systems and fully removing moisture Fire and explosion risks are also prominent in methanol’s (Methanol Institute 2020). risk profile. Because methanol has a low flash point and burns with a nearly invisible flame, it poses serious hazards In the maritime sector, additional safety protocols are in industrial environments. Methanol vapors are particularly required. The 2021 DNV external safety study highlights dangerous as they can form explosive mixtures with air, com- the need for specific guidelines on methanol bunkering; it pounding the risk of fires and explosions in confined or poorly emphasizes the need for port facilities and ship operators ventilated areas. Facilities storing or transporting methanol to ensure they are adequately equipped to handle the fuel must implement stringent fire prevention measures, includ- safely. Appropriate training and safety measures will be ing adequate ventilation and the use of fire-resistant mate- essential as methanol use becomes increasingly common rials. Emergency fire response systems should also consider in this sector (DNV 2021). Spills and transportation risks must the challenge of detecting methanol fires due to its flame also be considered, as methanol’s toxicity and flammability characteristics. The nearly invisible nature of methanol can lead to large-scale hazards in the event of accidents flames also makes fire detection and firefighting particularly during transit. challenging; specialized sensors and fire suppression systems are required (IRENA and Methanol Institute 2021). In conclusion, while methanol offers significant advantages as an industrial feedstock and alternative fuel, its risks, Environmental risks arise when spills or leaks occur during especially related to toxicity, fire, explosion, environmental transport or storage. Methanol is biodegradable, and while contamination, and material degradation, require robust its environmental persistence is lower than that of many safety measures across its life cycle. From handling and other chemicals, large spills into water bodies can disrupt storage to transportation and use, mitigating methanol’s aquatic ecosystems by lowering oxygen levels and impair- risks demands strict regulatory compliance, regular safety ing aquatic life. Additionally, methanol’s ability to dissolve in audits, and investment in corrosion-resistant infrastructure. water means that contamination of groundwater and soil is a Moreover, the development of industry-specific guidelines, real risk, especially if containment measures are inadequate. particularly in emerging sectors such as maritime fuel appli- These risks demand careful monitoring, as even short-term cations, will be critical to ensuring that methanol’s hazards exposure to high concentrations can have harmful effects do not overshadow its benefits. For safe and effective use of on biodiversity. Minimizing methanol’s long-term ecological methanol in both industrial and fuel-related contexts, the 10 Safety aspects of hydrogen and its main derivatives: A literature review for policy makers priorities should be emergency preparedness, continuous 3 Hydrogen Safety Panel. With more than 20 years of expe- worker training, and the adoption of cutting-edge safety rience, the panel is led by the Pacific Northwest National technologies. Laboratory and includes more than 20 experts, includ- ing, among others, engineers, scientists, code officials, The Methanol Institute provides extensive resources on the safety professionals, and equipment providers. Their goal safe handling of methanol. The resources include guidelines, is to apply the best safety practices in a nonregulatory manuals, and technical reports that cover various safety manner. aspects, including detecting and extinguishing a methanol fire, health and safety modules, and guidelines for commu- US DOE—Hydrogen and Fuel Cell Technologies Office. The nication during crises. These resources are crucial for parties HFTO within the DOE also has a website offering a compi- handling methanol to ensure they are prepared for unfore- lation of many reliable resources on safety, codes and stan- seen incidents (Methanol Institute n.d.). dards (HFTO 2024). Where can policy makers find up-to-date Fuel Cell and Hydrogen Energy Association. The FCHEA is information on hydrogen safety? the United States’ leading industry association representing leading and innovative organizations that are advancing Hydrogen components must follow strict guidelines and the production, distribution, and use of clean, safe, and undergo third-party testing for safety and structural reliable hydrogen energy. It publishes the “Hydrogen and integrity Fuel Cell Safety Report,” a bimonthly electronic publication One of the most comprehensive resources regarding hydro- providing information on the development of hydrogen and gen safety is H2 Tools, a portal of the US Department of fuel cell codes and standards, and the related safety infor- Energy (DOE). The Pacific Northwest National Laboratory mation (FCHEA 2024). The FCHEA also manages the H2 Tools developed the H2 Tools Portal with support from the DOE’s Codes and Standards Database, focused on the worldwide Office of Energy Efficiency and Renewable Energy. development of over 400 hydrogen and fuel cell standards (H2 Tools 2024b). The goal of the portal is to support the implementation of practices and procedures that will ensure the safe handling Other relevant publications on regulations for the hydrogen and use of hydrogen in a variety of fuel cell applications. industry are listed below. The portal brings together and enhances the utility of a vari- 3 “Risk-Based Regulatory Design for the Safe Use of ety of tools and web-based content on the safety aspects Hydrogen”(OECD 2023). of hydrogen and fuel cell technologies to help inform those tasked with designing, approving, or using systems and facil- 3 “Regulatory Framework, Safety Aspects, and Social ities, as well as those responding to incidents. Acceptance of Hydrogen Energy Technologies” (chapter 6 in Tchouvelev, de Oliveira, and Neves 2018). Based on more than 20 years of experience, the portal has a section dedicated to fuel cell codes and standards, and another section dedicated to best practices (H2 Tools 2024a). “For safe and effective use of methanol in Among the resources collected in H2 Tools, two are of partic- both industrial and fuel-related contexts, the ular importance: priorities should be emergency preparedness, 3 The Center for Hydrogen Safety. A global nonprofit continuous worker training, and the adoption founded in 2019 to provide guidance, education, and collaborative forums on hydrogen safety and global best of cutting-edge safety technologies.” practices. Safety aspects of hydrogen and its main derivatives: A literature review for policy makers 11 Where do we go from here? by the International Organization for Standardization, the American Society of Mechanical Engineers, and the National Several practical policy recommendations are proposed Fire Protection Association. Label hydrogen storage areas to enhance the safety of hydrogen and its derivatives and equipment with warning signs, and establish clear com- The issue of hydrogen safety has been rigorously addressed munication protocols for informing personnel, contractors, by well-established standards and highly reputable institu- and emergency responders on hydrogen-related activities. tions. The implementation of these standards and measures is crucial for the safe handling of hydrogen. These recommen- Conduct risk assessments regularly to identify potential dations are directed at policy makers, authorities, inspectors, hazards associated with hydrogen. Mitigation strategies— and other interested stakeholders to promote widespread such as adequate ventilation, leak detection systems, and adherence to safety protocols and foster global cooperation emergency shutdown procedures—must be implemented to in hydrogen safety. ensure safety. Establish clear guidelines or recommendations—for exam- ple, the Anhydrous Ammonia Tank Car Checklist developed “Avoid regulations or policies that are overly by the Fertilizer Institute for the safety of ammonia tank trains. restrictive. This is especially relevant in the Following these procedures is especially relevant when han- dling these substances, given their safety requirements. Also, case of greener fuels, which hold significant other basic procedures, such as emergency response plans potential for the energy transition.” or drill emergencies, are recommended to promote workers’ safety and damage control in the case of an accident. Educate the public—and authorities—on the risk that Avoid regulations or policies that are overly restrictive— hydrogen, ammonia, and methanol production entail. The for example, those where innovation is burdened due to risk main hazardous properties of hydrogen and its derivatives reduction beyond the desired levels. This is especially rele- should be extensively communicated from a young age, and vant for certain applications of hydrogen and its derivatives, safe handling procedures should be emphasized. Personnel for example, greener fuels, which hold significant potential involved in handling, storing, and transporting hydrogen for the energy transition. should receive comprehensive training. Risks must be com- municated in an easy-to-understand manner—not only to the Follow safety-by-design principles, especially for complex public but also to government authorities—so that decisions technologies with significant in-use phases. This approach are made based on a thorough understanding of the risks. focuses on addressing safety concerns early in the design pro- cess, and balances innovation and precaution by front-load- Ensure that hydrogen storage facilities comply with rel- ing safety considerations. By minimizing risks from the outset, evant safety standards and implement stringent filling innovators can reduce the need for extensive mitigation and emptying protocols for storage tanks so as to prevent later in the product life cycle. Effective safety-by-design pressure from exceeding a safe threshold. Personnel must be practices require proactive collaboration among regulators, trained on safe handling practices, including the use of per- innovators, and stakeholders, ensuring regulatory prepared- sonal protective equipment, and must learn to implement ness and the development of appropriate safety frameworks procedures to minimize exposure during loading, unloading, and tools. Collaborative effort will increase innovation while and transfer operations. Hydrogen storage and distribution maintaining high safety standards. equipment must be regularly maintained and inspected. Take critical mitigation actions throughout the life cycle Ensure all operations comply with applicable codes and of electrolyzers and plants. The following is a list of some standards and adhere to relevant international safety essential mitigation actions to take during operation (Zygier standards and regulations, such as those recommended 2024): 12 Safety aspects of hydrogen and its main derivatives: A literature review for policy makers 3 Degradation management. Mitigating the risk of mem- 3 Proactive operational practices. Proactive measures such brane degradation is paramount to prevent failures. as pausing production when equipment operates outside Operators must diligently adhere to prescribed mainte- optimal parameters and developing effective purging nance schedules and procedures to sustain equipment’s and inerting procedures are essential safety practices. integrity. 3 Measures for gas handling and safety. Effectively remov- 3 Optimal operating conditions. Adhering to manufactur- ing flammable and oxidizing gases from processing ers’ specifications and consideration for local operational equipment minimizes losses and increases safety. Strict conditions are essential. adherence to hydrogen hazard management—including good housekeeping, detectors, operational protocols, 3 Early detection and monitoring. Continuous monitoring of and preventive measures against fuel-air mixtures and membrane and diaphragm conditions helps detect deg- ignition sources—ensures safe operations. radation early, thus reducing the likelihood of unexpected failures within the equipment’s projected lifespan. 3 Monitoring key parameters. Regular monitoring of criti- cal parameters such as gas purity, voltage, and current ensures optimal performance and early detection of potential issues. References and resources Ammonia Energy Association. 2024d. “Updated PGS-12 Code: Preparing for Increased Ammonia Imports to the Netherlands.” Accufacts Inc. 2022. Safety of Hydrogen Transportation by /ammo- Ammonia Energy Association, August 16, 2024. https:/ /pstrust.org/ Gas Pipelines. Redmond, WA: Accufacts. https:/ niaenergy.org/articles/updated-pgs-12-code-preparing-for- wp-content/uploads/2022/11/11-28-22-Final-Accufacts-Hy- increased-ammonia-imports-to-the-netherlands/. drogen-Pipeline-Report.pdf. Calabrese, M., M. 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