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.

One morning a saltwell pump was placed in operation. Operation of this equipment requires that the Standard Hydrogen Monitoring System (SHMS) cabinet be in operation. Later that morning, during the morning surveillance rounds, the Standard Hydrogen Monitoring System (SHMS) cabinet was found not to be in the operational mode.

On the previous day, the night shift saltwell operator assigned to run the saltwell pump had placed the SHMS monitor in operational mode; however, the saltwell system was not started at this time. Shift turnover was conducted and the condition of the SHMS was turned over to the appropriate saltwell operator and shift manager. During the day shift the day shift operator assigned to the complex received approval from the operations engineer to place the SHMS view more

A violent reaction occurred while hydrolyzing metal in water. The reactive metal treatment began with a review of the chemical inventory and setup of reaction vessels. The sodium metal was cut in shavings and added one at a time to the reaction vessel. After the second addition, an argon purge was added to disperse hydrogen gas faster. After approximately 10 pieces had been treated, the glass beaker shattered, releasing the contents of the reaction vessel (1 liter) inside the hood and causing the chemist's hand to receive superficial cuts. The process was being performed under a hood with all safety equipment in place. The employee was in personal protective equipment (PPE), but did receive two cuts on his hand through the glove. The treatment of reactive metals was being view more

A facility representative observed pipe-fitters enter a containment tent around a riser with a tool bag that contained a mixture of steel and copper/beryllium tools. The top flange was loosened using a copper/beryllium socket and a steel torque wrench. When questioned, the pipe-fitters correctly stated that this was allowable for initial loosening and tightening of these bolts. A copper/beryllium ratchet was used to accomplish the bolt removal. The bonded riser was shifted to allow access for the IH technician. The standard hydrogen monitoring system (SHMS) cabinet and local sample showed no hydrogen/flammable gas was present.

While the continuous vapor sample was being taken, the pipe-fitters proceeded to put together the copper/beryllium ratchet and socket with a 10" view more

A 30-milliliter (mL) vacuum bulb, equipped with a glass stopcock, containing one gram of pentacarbonyl manganese hydride exploded in a refrigerator. This caused the breakage of three other containers, releasing some contents into the refrigerator. The chemicals did not react. The refrigerator contained numerous reactive and flammable chemicals, mostly in glass containers.

The damaged containers were removed and relocated under a hood. The refrigerator was then examined for other breakage and inventoried. All breakage was cleaned up. The safety coordinator was notified and began an investigation.

The direct cause of the occurrence was the failure of a glass vacuum bulb, which either fractured due to some unforeseen chemical reaction forming hydrogen gas, or was unable to view more

The interior of a small high-temperature furnace, approximately 24 inches high by 18 inches wide, became contaminated with an unknown material later identified as magnesium. The furnace was disassembled to clean the unknown material from the interior surfaces, and while attempting to clean the bottom of the furnace, the technician tapped the upper lip of the furnace with a spatula and the magnesium flashed. The technician was stepping back from the furnace when the magnesium flashed. He received minor eye irritation and his eyebrows were singed.

Later that week the same technician was attempting to clean the interior surfaces of the top of the furnace and sprayed, as directed, the interior of the top with a water-based cleaning liquid which consisted of 91% water. He stepped view more

One afternoon, a hydrogen-monitoring system alarm sounded. The system isolated the building hydrogen gas distribution system from the source and purged the distribution piping with argon. Activities were terminated and personnel were immediately evacuated.

Prior to re-entry, the hydrogen system was walked down to ensure that it was in a safe state and that the remote indicator showed no hydrogen present in the facility. Normal operations were suspended until the cause of the alarm could be determined.

The cause of the alarm was not escaping hydrogen gas, but drift in one of the eight monitoring system sensors. The sensor was recalibrated and the monitoring system determined to be functioning properly. The gas distribution system was recharged with hydrogen and verified as view more

Facility management confirmed that a hydrogen gas cylinder did not comply with the limiting condition for operation (LCO) for flammable gas control systems in the lab's safety requirements. Earlier erroneous calculations had shown that a release of the entire contents of the cylinder into the hood could not reach the lower flammability limit (LFL).

The facility manager determined that the LCO was applicable and immediately entered the action statement in the safety system, which required immediate termination of normal operations in the affected wing of the building. Because normal operations had already been terminated in the wing for HVAC maintenance, further efforts to terminate normal operations were not necessary. The hydrogen cylinder was removed from the hood, thus view more

A small hydrogen fire occurred in a chemical process hood. A chemist was performing an experiment reacting manganese dioxide with hydrogen to produce manganese oxide and water. The chemist had left the process, which would take approximately one hour to complete, and was working in a nearby lab. While the chemist was gone, a second worker heard a pop, saw the hydrogen fire in the hood, and requested the activation of a fire alarm. A third employee in the area activated a manual fire alarm. The chemist, upon hearing the fire alarm, returned to the room, shut off the hydrogen fuel supply, and evacuated the facility. The hydrogen fire lasted for approximately one minute. The remaining small fire was extinguished about 10 minutes later with a HALON portable fire extinguisher by a view more

An unplanned shutdown of the hydrogen supply system occurred, affecting the hydrogen furnaces in the plant. The apparent cause was an inadvertent valve closing, which was contrary to the written procedure.

A preventative maintenance activity was being conducted on the hydrogen gas system. Shortly after starting that work, various hydrogen gas users notified the emergency response personnel that the hydrogen supply safety alarms sounded, indicating an interruption of the hydrogen gas supply. As a result, the hydrogen furnaces shut down. This shut down is an automated process which injects an inert gas (nitrogen or argon) to prevent the introduction of oxygen and its mixing with any hydrogen gas. All shut downs functioned as designed. As a precautionary measure, fire protection view more

A laboratory research technician entered a lab to begin preparing samples that were to ultimately be purged in an anaerobic chamber (glove box) located in that room. As the technician walked into the lab, she looked at the chamber to see if it was adequately inflated. This chamber is equipped with a gas concentration meter, capable of simultaneously displaying the oxygen and hydrogen concentrations of the chamber atmosphere. Under normal operating conditions, the atmosphere inside the chamber is comprised of 0% oxygen (as intended/desired for an anaerobic atmosphere), approximately 2-3% hydrogen, and with the remaining balance being nitrogen (approximately 98-97%). Under such normal operating conditions, the hydrogen concentration inside the chamber is less than the lower explosive view more