Severity
Incident
Leak
Yes
Ignition
No

Hydrogen leaked from a 9,000-gallon horizontal liquid hydrogen tank in the rear of a high-intensity lamp manufacturing facility. The facility manager noticed the leak during his normal morning rounds and initiated the plant's emergency response policy, which included calling the local fire department. A large vapor plume (actually condensed moisture in the air) was visible 200 feet above the tank. The technician for the hydrogen supplier arrived on site, thawed out the ice buildup around the gland nut from which the leak originated using warm water, and tightened the nut, thus ending the problem. The technician verified that the leak originated from packing material around the valve that had come loose because of the recent extreme cold weather.

The fire department requested that the facility not shut down, but rather continue operations to draw normal levels of hydrogen from the tank. A checkpoint was established near the tank side of the building where hydrogen level readings were taken and reported every 5 minutes. Employees of the plant were notified to exit the front of the building in the event of an evacuation signal. As hoses were turned on by the fire department, a drop in water pressure tripped the internal alarm, causing an evacuation of the plant. All employees were accounted for and were asked to return to work, as this was a false alarm condition. Two local streets were closed, radios, cell phones, and other electronic devices were shut down within a 500-foot safety zone to eliminate any static electricity that could ignite the hydrogen gas, and airplanes were diverted from their normal flight path to the local airport. Firefighters set up combustible gas monitors inside the building, but no gas was detected. The incident lasted approximately two hours.

Incident Date
Jan 19, 2009
Equipment
  • Piping/Fittings/Valves
  • Valve
Damage and Injuries
Probable Cause
Contributing Factors
Characteristics
When Incident Discovered
Lessons Learned

Excessive venting of hydrogen from the tank due to lower facility consumption, in combination with extreme temperature conditions, placed thermal stress on the gland nut, causing a leak. The low consumption of hydrogen resulted from the shutdown of some production equipment and the delay of additional production equipment coming online. The tank size is too large for the facility's current hydrogen demand.

The hydrogen supplier will conduct annual training on handling all types of gases used by the facility and will include the local fire department in this training. The facility will continue daily rounds to look for visual evidence of leaks, and the hydrogen supplier will exchange the 9,000-gallon tank for a smaller 4,500-gallon tank to significantly reduce pressure build up from lower usage.

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