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 researcher was using numerous compressed gases in his lab. To facilitate reconfiguring his experimental apparatus, he installed "quick-disconnect" fittings on flexible tubing connected to his compressed gas cylinders/regulators. He also fitted all of the equipment that needed gas with complementary "quick-disconnect" fittings.

The day of the incident, he needed to purge his IR spectrometer with nitrogen as the element heated up. He mistakenly attached the "quick-disconnect" fitting from a cylinder of 10% nitrogen and 90% hydrogen to the "quick-disconnect" fitting on his spectrometer. As soon as the gas started flowing and he switched on the element, the instrument exploded, completely destroying a $6,000 piece of equipment. Only minor view more

A researcher was unplugging an electrical cord when 1/8-inch copper tubing supplying nitrogen to a gas chromatograph came in contact with the energized electrical plug, causing an electrical arc. This caused a hole in the copper tubing. A nearby hydrogen line was unaffected.

The bottled gas supply was shut off. Craftsmen were brought in to reinstall the copper tubing, at a safe distance from the electrical outlet.

An over-pressurization of two 55-gallon drums of waste phosphoric acid resulted in a material failure of the drum bottoms, releasing the contents of both drums (about 100 gallons) onto the facility floor. The spillage was collected within the sumps that are part of the facility's spill control system. The waste material had been packaged into DOT-specified containers earlier that day and the drums were placed into an assigned storage cell. That evening a staff member heard a noise in the high bay where hazardous wastes are stored. Upon investigating, he discovered the breached drums and spilled material.

The only material released to the environment was hydrogen gas. The maximum concentration of hydrogen released into the facility was 0.035%, well below the lower view more

Only 25 minutes after the normal work shift ended, an explosion occurred at a hydrogen storage and use facility that had been in a non-operational mode for several months while undergoing modifications for future tests. No one was in the facility at the time of the explosion. The event was viewed about 30 seconds after the explosion by two engineers in a blockhouse 1000 feet away. Authorities were notified and calls were placed to other personnel needed to secure the area. About 8 minutes later, the engineers moved to a vantage point about 450 feet from the facility. There they viewed heat waves rising from a central location on the test pad, heard popping sounds similar to gaseous hydrogen (GH2) venting on a burn pond, and suspected that a hydrogen fire was in process. They returned view more

An accident occurred during setup for a popular hydrogen-oxygen balloon science demonstration at a local public school. The demonstrator suffered painful second-degree burns to his right forearm and was taken to the hospital. The paramedics feared that grave respiratory damage (due to flame inhalation) might have occurred.

The demonstrator had transported 15 helium-quality balloons, pre-filled with a hydrogen-oxygen mixture, in a large, black, polyethylene garbage bag. During the setup, he opened the bag to remove a single balloon for stringing and floating. Without warning, the entire bag of balloons detonated violently. Fortunately, the incident occurred an hour prior to the program and no one else was near. It was also fortunate that only a small box caught fire and none of view more

During the early morning hours on a Tuesday, a university support staff member was preparing for an off-campus community outreach program for high-school-age students in the community. One of the program demonstrations was to show students the reaction energy and properties of the hydrogen + oxygen = water chemical reaction. It was a demonstration that the professor and the staff member overseeing the program had done for over 15 years with no incidents ever occurring.

To prepare for the demonstration, eight balloons were filled, four with pure hydrogen and four with the proper combination of hydrogen and oxygen. The balloons were placed into a larger plastic garbage bag and carried outside to a university-owned SUV located next to the building's loading dock. The bag of view more

In the fall of 2007, the operations team began a procedure (a written procedure was being followed) to sample the liquid hydrogen (LH2) storage vessels ("tanks"), and associated transfer system. This procedure was being performed to determine the conditions within the system, and if necessary, to purge the system of any excess gaseous hydrogen (GH2) in preparation for reactivation of the system. The system had not been used since 2003.

The LH2 storage system contains two (2) spherical pressure vessels of 225,000 gallons in volume, with a maximum working pressure (MAWP) of 50 psig. Eight-inch transfer piping connects them to the usage point. Operations began with activation of the burnstack for the LH2 storage area. Pneumatic gaseous nitrogen (GN2) systems in the view more

A hydrogen explosion occurred in a university biochemistry laboratory. Four persons were taken to the hospital for injuries. Three of these were treated and released shortly thereafter; the fourth was kept overnight and released the following evening. All of the exterior windows in the laboratory were blown out and there was significant damage within the laboratory. One sprinkler was activated that controlled a fire associated with a compressed hydrogen gas cylinder.

First responders from the local community and the university campus were quickly on the scene. Once the injured were attended to and the site secured, response efforts focused first on assessing potential hazards (electrical, fire, hazardous materials, etc). Campus personnel worked into the night to board up windows view more

Severe vibrations caused by broken low-pressure turbine blades damaged the main turbine generator at a nuclear power plant. These vibrations also caused multiple hydrogen leaks at equipment connections to the generator, resulting in hydrogen flames outside of the generator casing that caused minimal damage to the facility. Hydrogen is used to internally cool the plant's electric generators. Water from the fire suppression system and oil released from the turbine lube oil system during the event were contained within the plant, resulting in no impact to the environment. The plant's nuclear systems were unaffected by the event.

During a test run of a hybrid, fuel-cell-powered passenger ship, the on-board lead-acid batteries overheated, resulting a fire in the battery compartment. The local fire department was able to quickly put the fire out.The batteries had been replaced a few days prior from the battery supplier and were in the process of being tested for the first time on the river.The batteries are charged slowly from the fuel cell and the power is made available for cast-off and driving maneuvers.It was systematically confirmed that the fire, which was comparable to a conventional cable fire, posed no risk to the fuel cells or the hydrogen storage tanks. There was never a danger to the captain or crew, and the fire department confirmed that there was never a risk of fire spreading to the other view more