What is Lessons Learned?

What is H2LL?

This database is supported by the U.S. Department of Energy. The safety event records have been contributed by a variety of global sources, including industrial, government and academic facilities.

H2LL is a database-driven website intended to facilitate the sharing of lessons learned and other relevant information gained from actual experiences using and working with hydrogen. The database also serves as a voluntary reporting tool for capturing records of events involving either hydrogen or hydrogen-related technologies.

The focus of the database is on characterization of hydrogen-related incidents and near-misses, and ensuing lessons learned from those events. All identifying information, including names of companies or organizations, locations, and the like, is removed to ensure confidentiality and to encourage the unconstrained future reporting of events as they occur.

The intended audience for this website is anyone who is involved in any aspect of hydrogen use. The existing safety event records are mainly focused on laboratory settings that offer valuable insights into the safe use of hydrogen in energy applications and R&D. It is hoped that users will come to this website both to learn valuable lessons from the experiences of others as well as to share information from their own experiences. Improved safety awareness benefits all.

Development of the database has been primarily supported by the U.S. Department of Energy. While every effort is made to verify the accuracy of information contained herein, no guarantee is expressed or implied with respect to the completeness, causal attribution, or suggested remedial measures for avoiding future events of a similar nature. The contents of this database are presented for informational purposes only. Design of any energy system should always be developed in close consultation with safety experts familiar with the particulars of the specific application.

We encourage you to browse through the safety event records on the website and send us your comments and suggestions. We will continue to add new records as they become available.

How does H2LL work?

If you have an incident you would like to include in the H2LL database, please click the "Submit an Incident" button at the top of the page. You will be asked for a wide range of information on your incident. Please enter as much of the information as possible. In order to protect your and your employer's identities, information that may distinguish an incident (your contact information, your company's name, the location of the incident, etc.) will not be displayed in the incident reports on H2LL.

Lessons Learned Corner

Visit the Lessons Learned Corner Archives.

Key themes from the H2Incidents database will be presented in the Lessons Learned Corner. Safety event records will be highlighted to illustrate the relevant lessons learned. Please let us know what you think and what themes you would like to see highlighted in this safety knowledge corner. You can find all the previous topics in the archives.

A student cleaned catalyst that was being used for a fuel cell membrane electrode assembly from a spatula. He then placed the contaminated paper towel into a waste container that contained other waste that was wet with alcohol. The alcohol reacted with the catalyst, igniting a fire within the waste container. The fire was extinguished with a beaker of water.

An explosion occurred within the hydrogen processing system of a chemical plant that produces sodium chlorate for bleaching pulp and paper. The chemical process utilizes electrolytic cells and is pH-dependent. Hydrogen is produced as a byproduct and is utilized as a fuel.

At the time of the incident, the plant was at an abnormal operating level of 25% capacity. A non-routine maintenance operation to repair high-pH liquid piping was in progress. To assist, operations personnel rerouted the high-pH liquid stream to the plant sump. However, in doing this, the liquid eventually made its way back into the electrolytic process by design. Ultimately this created the root cause of the explosive condition in that the pH of the electrolytic process increased faster than the computer- view more

A hydrogen leak and subsequent explosion occurred when tie-downs on a hydrogen transport trailer securing hydrogen cylinder packages failed. The tie-down failure caused the hydrogen cylinder packages to fall off the trailer and eject some cylinders onto the roadway (see Figure 1). The cause of the accident is unknown, but it appears to be unrelated to hydrogen (i.e., likely tie-down strap weakness or error in properly securing tie-downs). The cylinders contained compressed hydrogen gas at 200 bar (2900 psi). The accident caused some hydrogen cylinders to leak and the associated cylinder package plumbing systems were breached. A spark or other local heat source (e.g., from a nearby vehicle motor) ignited the leaking hydrogen and caused a deflagration/explosion that damaged a car view more

A hydrogen leak occurred when hydrogen tube trailer traveling on a rural roadway left the road, overturned on its side, and resulted in a single hydrogen tube valve being opened or broken. The cause of the accident is unknown, however, it appears to be unrelated to hydrogen (i.e., it is likely that human driving errors caused the accident). The hydrogen tubes contained compressed hydrogen gas at 200 bar (2,900 psi). The back end of the tube trailer containing the high-pressure hydrogen plumbing and valves contacted the ground and resulted in the valve opening or breaking and losing all the hydrogen from one tube. The tube/valve that leaked was located on the bottom tier in the center position. The first firefighter crew to arrive at the accident scene verified that the leakage was view more

A hydrogen fire occurred in an early morning accident involving a hydrogen tube trailer and multiple vehicles on a rural highway. The cause of the collision is unknown, however, it appears to be unrelated to hydrogen (i.e., it was likely human driving errors). The hydrogen tubes contained compressed hydrogen gas at a pressure of 15 bar (218 psi). The accident caused a leak in the hydrogen plumbing system and deformed one of the hydrogen tubes, resulting in a 10-centimeter (4-inch) longitudinal crack from which hydrogen began to leak (see Figures 1 and 2). Fire from the conventional vehicles trapped under the hydrogen tube trailer during the accident ignited combustible components on the tube trailer (tires and fuel/oil), and subsequently the leaking hydrogen. Emergency crews arrived view more

During normal operations, a two-inch flame was discovered emanating from a pinhole leak in a hydrogen line at an aircraft parts manufacturing facility. Hydrogen was not in use by any process in the facility at the time. The flame was discovered by a contractor who was about to start welding on scaffolding about 3-5 feet away. Before starting, the welder searched the immediate area for any signs of fire per his training. When he spotted the flame, he called his supervisor.

An operator tried to put out the fire with a fire extinguisher, which resulted in the flame enlarging by one inch. All employees and contractors were instructed to leave the area, and the EHS team leader called 911 and informed the fire department that there was a hydrogen fire at the facility. She then put an view more

During a refueling event, the operator activated the fueling lever in the wrong sequence. The vehicle filled to proper pressure, but filled faster than normal. Under different circumstances, this could have resulted in overheating of the receiving fuel tank.

A fire began in the compression skid for a high-pressure hydrogen fueling station. The initial source of fire was likely a release of hydrogen from a failed weld on a pressure switch. The initial fire cascaded to three stainless steel line failures, release of glycol coolant, and release/combustion of compressor oil. Non-metallic seals and hoses containing hydraulic fluid and coolant melted/burned and caused leakage of the fluid, which was mostly consumed by the fire. The local fire department responded and contained the situation by shutting off the power supply and spraying water on nearby equipment. The compressor skid was a loss and the fire caused moderate damage to surrounding equipment.

Hydrogen leaked from a 9,000-gallon horizontal liquid hydrogen tank in the rear of a high-intensity lamp manufacturing facility. The facility manager noticed the leak during his normal morning rounds and initiated the plant's emergency response policy, which included calling the local fire department. A large vapor plume (actually condensed moisture in the air) was visible 200 feet above the tank. The technician for the hydrogen supplier arrived on site, thawed out the ice buildup around the gland nut from which the leak originated using warm water, and tightened the nut, thus ending the problem. The technician verified that the leak originated from packing material around the valve that had come loose because of the recent extreme cold weather.

The fire department view more

A hose clamp failed on a low-pressure vent line from a hydrogen reactor experiment and effluent was leaked into the laboratory. Unburnt hydrogen in the effluent stream triggered the low-level hydrogen alarm. The hose clamp was resecured and other hose clamps were checked for proper tightness.