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H2Tools: Hydrogen Lessons Learned

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An incident is an event that results in:
  • a lost-time accident and/or injury to personnel
  • damage to project equipment, facilities or property
  • impact to the public or environment
  • an emergency response or should have resulted in an emergency response.
A near-miss is an event that, under slightly different circumstances, could have become an incident. Examples include:
  • any unintentional hydrogen release that ignites, or is sufficient to sustain a flame if ignited, and does not fit the definition for an incident
  • any hydrogen release which accumulates above 25% of the lower flammability limits within an enclosed space and does not fit the definition of an incident
A non-event is a situation, occurrence, or other outcome relevant to safety that does not involve a particular incident or near miss. For example, a non-event might consist of a failed safety inspection.

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The left navigation on the H2LL website is two-fold.

  1. Links
    By clicking on the links in the left navigation, you can view all incident reports matching that lone selection. For example, clicking on "Minor Injury" within the "Damages and Injuries" category will return a list of all incident reports that included "Minor Injury."
  2. Checkboxes
    Selecting checkboxes next to navigation items—then clicking the "Update Criteria" button—will provide a restrictive search on the criteria selected. Each selected checkbox will restrict the results to only incident reports that include that criteria. For example, selecting the checkbox next to "Minor Injury" in the "Damages and Injuries" category and selecting the checkbox next to "Decision Making" in the "Factors" category will return a list of all incident reports that included both "Minor Injury" and "Decision Making."


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Latest Reports

Reacting Ammonia Borane Exposure to Air

Partially spent ammonia borane reaction with water

Total Events Reported: 216 (show all)

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New! Lessons Learned Corner

Hydrogen Leak Detection

Ventilation of Facilities where Hydrogen is Used

Lessons Learned Archives

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.

More About H2LL...

How does H2LL work?

You can access incident reports on H2LL in a number of different ways. Here on the home page, you can go directly to the latest posted incidents using the navigation in the box to the right labeled "Latest Reports." The bottom of this box also contains a total for the number of incident reports in the system. By clicking the "show all" text next to this number, you can view a complete, alphabetical list of incidents.

To look for incidents related to specific details, you can use the left navigation. The five main headings—Settings, Equipment, Damage and Injuries, Probable Causes, Contributing Factors—will help you drill through the collection of incidents to find those that interest you. To see a graphical representation of the number of incidents associated with each of these main headings, simply click on the heading and then mouse over the chart to view a larger image. At any time, you can also use the Advanced Search form, found at the top of the page, for some more options to search the database.

If you have an incident you would like to include in the H2LL database, please visit the Submit an Incident page. This page will ask 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.