Explosion on a Hydrogen Production Unit
At approximately 8:45 a.m. an employee was troubleshooting a thermal chamber, evaluating a Hydrogen on Demand (HOD) unit. The chamber was reported inoperative that morning. Two units were being tested on a work bench and they were connected by an exhaust hose to an HOD inside the test chamber. The gas was not properly exhausted and began to back up into the hose that was attached to the HOD. The employee removed the side panel on the chamber and it exploded while he were standing in front of it. He was killed by the explosion.
Event Date
May 22, 2012
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Causes
Cause Comments
The IMMEDIATE CAUSE was the unexpected and undetected presence of hydrogen in the testing chamber when it was open to air. The ROOT CAUSE was a series of shortcoming in the design of the whole installation, including a lack of operative and maintenance procedures
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
hydrogen on demand unit, testing chamber
Storage/Process Medium
Location Type
Location description
Industrial Area
Operational Condition
Pre-event Summary
The chamber was reported inoperative that morning and was being troubleshooted.
Consequences
Number of Injured Persons
1
Lessons Learned
Lessons Learned
The OHSA investigation found that the employer failed to provide employees and a place of employment free from recognized hazards (explosion hazards when the employer failed to ventilate hydrogen gas adequately).The following conditions increased the potential for an explosion: (1) Hydrogen was being created by hydrogen-on-demand (HOD) units being tested and the exhaust system was not designed, constructed, installed, tested and maintained properly to provide safety to life from fires and explosions.(2) Procedures were not developed, documented and utilized for the control of potentially hazardous energy when employees were engaged in activities with the environmental test chamber. The exhaust hoses used to exhaust the hydrogen gas created on the test bench were connected to an exhaust hose on the HOD inside the test chamber. The air conditioning section of the chamber contains open wire heating elements. (3) Areas designated as hazardous (classified) locations were not properly documented.(4) The equipment was not approved for the class of location and for the ignitable or combustible properties of the specific gas that would be present.(5) The employer did not develop a material safety data sheet for the hydrogen generated by the electrolysis process
Event Nature
Emergency Action
The local fire department responded and pulled the employee from the building.
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Source Category
References
References
OHSA Report 0524200
https://www.osha.gov/ords/imis/establishment.inspection_detail?id=44407…
(accessedOctober2023)