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 pinhole at the base of a hand-held hydrogen torch, allowed hydrogen to leak. In the process of lighting a second torch, the leaking hydrogen was ignited. The operator, being startled by the "pop" of the lighted hydrogen allowed the #2 torch to drop and hang by its hose support approximately 6" from the floor. The hydrogen and oxygen hoses on the #1 torch were burned through and hung approximately 12" from the floor. The free burning #1 hose burned the #2 hydrogen and oxygen hose assembly through, causing both hoses assemblies to burn without valve control. The hose size is 1/4" and is used in various areas of the plant.

While filling a sample cylinder with compressed hydrogen gas, a quick-disconnect coupler fitting came loose within a stainless steel laboratory hood, allowing a small purge of the hydrogen gas to escape directly into the hood through ~1/4-inch Tygon tubing. The stainless steel quick-disconnect fitting struck the stainless steel bottom of the laboratory hood and the hydrogen gas caught fire. It is not known what caused the hydrogen gas to catch fire. The most likely sources of a spark was from metal-to-metal contact of the quick-disconnect fitting with the laboratory hood floor, or the discharge of static electrical charge generated by flow of hydrogen gas through Tygon tubing. The resultant narrow jet of fire, directed toward the left side of the laboratory hood, extinguished itself view more

Incident Synopsis
While disconnecting a liquid H2 fill line from a liquid H2 trailer, liquid H2 escaped, burning a second man who was holding the hose. The man was burned on his hands and on his stomach.

Cause
The liquid H2 shut off valve was partially open, but both men assumed it was closed. Prescribed clothing was being worn.

Incident Synopsis
At an offsite liquid H2 fill station, a liquid hydrogen trailer hit a gaseous H2 purge shut off valve handle. Tubing attached to the purge valve was bent on both ends but did not leak.

Cause
The driver was not sufficiently careful in approaching the liquid H2 system fill point.

A small electrical fire occurred (due to what is believed to be an electrical short circuit) inside a fuel cell test stand. Subsequently, a nearby hydrogen line made of flexible tubing was melted through and ignited the hydrogen, causing a small fire.

The electrical fire was easily extinguished. The hydrogen flame was extinguished by snuffing the flame, shutting off the gas lines and power to the test stand. No one was injured, but damage was incurred in the test stand.

Causes

An electrical short circuit occurred, causing a small electrical fire.
Electrical fire caused a flexible tubing hydrogen line to melt, thus exposing hydrogen to the fire.

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.

A facility uses small crucibles to heat precious metals within a fume hood, with natural gas as the fuel source for the Bunsen burner. Hydrogen is fed into the crucible at low pressure (<20 psi) to control the atmosphere within the vessel in order to prevent oxidation. The hydrogen is routed through a manifold with flexible tubing, which is connected to a ceramic tip and fitted into the crucible through a small opening in the crucible's lid. The hydrogen is consumed in the process. The facility believes that the hydrogen tubing developed a leak which eventually ignited. The plastic interior of the fume hood ignited and started to spread. The person working in the area shut off the natural gas and hydrogen (they had valves at the hood) and used a halon extinguisher in the view more