Severity
Incident
Leak
Yes
Ignition
No

A 2000-psia-rated gas cylinder (nominal size 10"x1 1/2") was being filled with hydrogen to a target pressure of 1500 psia. The cylinder suffered a failure at an indicated pressure of 1500 psia during filling. Investigation of the failure subsequently revealed that a faulty digital readout had allowed the cylinder to be over-pressurized. There were no safety consequences due to the failure and no damage to the facility or equipment. The cylinder was being filled in a test vault that was specially designed for the high-pressure burst testing of pressure vessels and components. While no over-pressure cylinders were released from the laboratory for use, this incident is being reported to address the potential and subsequent lessons learned.

Investigations revealed that the pressure transducer was faulty and the actual pressure could have been more than five times the indicated pressure. Although the high-pressure manifold has rupture-disk protection, the rupture disk was not adequately sized to provide protection for this type of cylinder. Thus, the failed digital pressure instrument was the single barrier to over pressurizing a cylinder.

Incident Date
Mar 17, 1999
Setting
Equipment
  • Pressure Relief Devices
  • Pressure Transducer
  • Pressure Relief Devices
  • Burst Disk
Damage and Injuries
Probable Cause
Characteristics
When Incident Discovered
Lessons Learned

This occurrence underscores the importance of completing a hazard analysis for each different process. Non-safety-related systems or equipment may be used for purposes other than their primary purpose so long as potential hazards are identified and engineering and administrative controls are applied to eliminate or minimize them. The filling of lecture bottles seemed to fall within the safety envelope previously established for high-pressure testing; however, the rupture of a cylinder revealed an unanticipated potential to release an overfilled gas cylinder to laboratory personnel.

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