Release and Ignition of Hydrogen Due to a Trailer Collision
A tractor - semitrailer with horizontally mounted cylinders filled with compressed hydrogen struck a northbound pickup truck that had veered in front of it.The tractor-semitrailer then went out of control and overturned while continuing along the highway. It went off the road to the east and travelled 300 or more feet before it stopped (ca. 100 m). During the process, some of the cylinders, valves, piping, and fittings at the rear of the semitrailer were damaged and released hydrogen. The hydrogen ignited and burned the rear of the semitrailer. In the meantime, the pickup truck had also run off the road. The pickup truck's fuel line ruptured, resulting in the truck being destroyed by fire.As a result of the accident, the truck driver was killed, and the driver of the pickup truck was seriously injured. Residents of five homes in the vicinity of the accident were asked to evacuate, and the highway was closed for more than 12 hours. Damage, clean-up, and lost revenues were estimated at $155,000.
Event Date
May 1, 2001
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Causes
Cause Comments
Direct cause was collision of the hydrogen trailer with another vehicles.Contributing to the severity of the accident were the inadequate standards aiming at protecting and shielding cylinders, valves, piping, and fittings and at securing cylinders on the semitrailer.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
trailer with 10 horizontally mounted hydrogen cylinders
Storage/Process Medium
Actual Pressure
170
Design Pressure
170
Location Type
Location description
Countryside Road Or Highway
Pre-event Summary
The metal cylinder had nominal working pressure of 2,500 psig (ca. 170 bar) and a volume of 14100 cubic feet (ca. 400 m^3).
Lessons Learned
Lessons Learned
As a result of its investigation, the National Transportation Safety Board made the following safety recommendations to the Research and Special Programs Administration:1. Modify the Code of Federal Regulations to clearly require that valves, piping, and fittings for cylinders that are horizontally mounted and used to transport hazardous materials are protected from multi-directional forces that are likely to occur during accidents, including rollovers. 2. Require that cylinders that transport hazardous materials and are horizontally mounted on a semitrailer be protected from impact with the roadway or terrain to reduce the likelihood of their being fractured and ejected during a rollover accident. 3. Revise the information about hydrogen in the North American Emergency Response Guidebook so that it specifically identifies the unique chemical and flammability properties of hydrogen.
Event Nature
Emergency Action
A very detailed Emergency Response record is given in the HAZMAT report in the references.
Release Type
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Flame Type
Source Category
References
References
Full NTSB report:
https://www.ntsb.gov/investigations/Pages/DCA01MZ001.aspx
(accessed Dec 2022)
NTBS news 17 September 2002
https://www.ntsb.gov/news/press-releases/Pages/NTSB_Determines_that_Sec…
Report of the National Transportation Safety Board (NTSB) 17 September 2012,
available at the link given (accessed June 2020)