Severity
Near-Miss
Leak
Yes
Ignition
No

The hydrogen sensor at a hydrogen fueling station detected a slight leakage from the ground packing of the flow control valve during refueling. The refueling operation was stopped immediately. The leak was stopped by tightening the ground packing sealing screw, but it started leaking again in about a week.

The flow control valve was disassembled and inspected. Dust was found at the ground seal and the packing was distorted. Leakage was believed to be due to the dust invasion and repeated tightening of the sealing screw. The packing had been used for four years and two months without replacement.

Incident Date
May 01, 2007
Setting
Fueling Station
Equipment
  • Piping/Fittings/Valves
  • Valve
Damage and Injuries
None
Probable Cause
Inadequate Maintenance
Contributing Factors
Incomplete O&M procedures
Characteristics
High Pressure (> 100 bar)
Lessons Learned

The packing in the flow control valve should be replaced periodically. A planned investigation will determine the optimum time period for packing replacement.

Post date
September, 2017

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