CHECK OUT OUR MOST RELEVANT INCIDENT LISTINGS! 

Disclaimer: The Lessons Learned Database includes the incidents that were voluntarily submitted. The database is not a comprehensive source for all incidents that have occurred.

The visiting intern had several years of experience in research projects and tasks that were similar to those in progress at this laboratory. This led to the incorrect assumption that formal introductory training for this laboratory was…

Failure of a diaphragm is not infrequent, but the seizure of the main nut threads is very rare. The manufacturer claimed this had never occurred before with this type of unit. The broken plunger is likely the result of poor instructions/…

For the use of mechanical fittings in hydrogen service, administrative controls should be in place, as in this case, to ensure that leak testing is conducted on a regular basis. It should never be assumed that every fitting is tight. Additional…

Investigation determined that internal galling has caused the failure rendering the needle valve unusable. The galling was caused by a stainless steel stem acting against a stainless steel seat. This failure mode had been observed before and the…

Verify that all PRDs contain fuse-backed adapters.
Explore elimination of rupture disk PRDs and substitution of spring-style relief valves.
Develop new hydrogen unloading procedure using a written checklist. * Add instrumentation to…

This incident highlights the need to properly design safety interlocks. These safety interlocks need to be carefully incorporated into the initial building/plant designs and should consider all of the unexpected occurrences, such as the…

Operation and management of the hydrodesulfurization unit should be strengthened to account for abnormal phenomena such as local corrosion.
The safety review system for remodeling existing equipment and facilities should be strengthened.…

The plant tried to increase production and decrease workload, but failed to notice the potential negative outcomes of this change.
It is necessary to thoroughly simulate all potential negative outcomes of a change in procedures.

The dilution water for making a polythionic acid aqueous solution was changed from industrial water to pure water to lower the chlorine concentration in the piping.
Water that accumulated in the drain was removed before heating began.…

Fail-safe position of control valves in supply lines must be set correctly to prevent damage to pressure vessels.

Recommendation

Set all valves for fail safe operation (open or closed) according to needs before installation in…

Hazards should be eliminated to the extent possible rather than depending on workers to follow an operations manual.

Potassium carbonate draw-off operations should be improved, and the operations manual should be revised. The manual should…

This incident emphasizes the need for proper gas detection and ventilation systems, as well as fire suppression systems, in laboratories using and storing hydrogen. This is especially true when open flame burners are in close proximity.…

Routine maintenance activities on pressurized hydrogen systems should be conducted per written design specifications. The procedures should provide detailed oversight regarding bolt, nut and fitting replacements or repairs. A formal review…

Although a functional fire protection system would have helped to extinguish the fire, a properly installed hydrogen detection system, coupled with a properly designed ventilation system, could have prevented the incident altogether.Hydrogen…

The uncontrolled release of hydrogen occurred as a result of the rupture of the No. 6 hydrogen storage tube’s burst disc. This disc failed in response to being overloaded by mechanical stresses developed as water expanded and formed ice while in…

Lessons Learned
Construction errors are difficult to detect once construction is complete. It is important to develop and use a systematic oversight process for minimizing construction errors during the construction process.

Lessons Learned The site initiated the establishment of a field patrol and strengthened their onsite monitoring of mechanical equipment during a plant-wide temperature rise.

Quantitative control of tightening torque on bolts should be…

One needs to take extreme care with both new and supposedly spent hydride samples; the spent materials may contain pockets of unoxidized alanates that could react violently when being transferred.
Work with small samples so if something…

Now, when conducting a sulfur deprivation test, vessels are ventilated to prevent over pressurization and safely facilitate the release of excess hydrogen.

Maintain an internal process for verifying component wetted material compatibility for intended use as part of the procurement process for hydrogen system equipment. It is critical that component parts be appropriately rated for the materials,…

Key:

  • = No Ignition
  • = Explosion
  • = Fire
Hydrogen Incident Summaries by Equipment and Primary Cause/Issue
Equipment / Cause Equipment Design or Selection Component Failure Operational Error Installation or Maintenance Inadequate Gas or Flame Detection Emergency Shutdown Response Other or Unknown
Hydrogen Gas Metal Cylinder or Regulator   3/31/2012
4/30/1995
2/6/2013
4/26/2010 12/31/1969     3/17/1999
11/1/2001
12/23/2003
Piping/Valves 4/4/2002
2/2/2008
5/11/1999
4/20/1987
11/4/1997
12/31/1969
8/19/1986
7/27/1991
12/19/2004
2/6/2008
10/3/2008
4/5/2006
5/1/2007
9/19/2007
10/31/1980
2/7/2009 1/24/1999
2/24/2006
6/8/1998
12/31/1969
2/7/2009

9/1/1992
10/31/1980

10/3/2008  
Tubing/Fittings/Hose   9/23/1999
8/2/2004
8/6/2008
9/19/2007
1/1/1982 9/30/2004
10/7/2005
  10/7/2005  
Compressor   10/5/2009
6/10/2007
8/21/2008
1/15/2019
    10/5/2009 8/21/2008  
Liquid Hydrogen Tank or Delivery Truck 4/27/1989 12/19/2004
1/19/2009
8/6/2004 12/31/1969   1/1/1974 12/17/2004
Pressure Relief Device 7/25/2013
5/4/2012
1/15/2002
1/08/2007
12/31/1969        
Instrument 1/15/2019 3/17/1999
12/31/1969
2/6/2013
    11/13/73    
Hydrogen Generation Equipment 7/27/1999     10/23/2001      
Vehicle or Lift Truck   7/21/2011         2/8/2011
12/9/2010
Fuel Dispenser   8/2/2004
5/1/2007
6/11/2007
9/19/2007
  2/24/2006
1/22/2009
     
Fuel Cell Stack            

5/3/2004
12/9/2010
2/8/2011

Hydrogen Cooled Generator       12/31/1969
2/7/2009
     
Other (floor drain, lab
anaerobic chamber,
heated glassware,
test chamber,
gaseous hydrogen
composite cylinder,
delivery truck)
  11/14/1994
7/21/2011
7/27/1999
6/28/2010
8/21/2008
12/31/1969
3/22/2018
    6/10/2019
  • = No Ignition
  • = Explosion
  • = Fire