First responders were dispatched to the waterfront area to investigate a possible explosion on an 85-foot dinner cruise boat that was moored there. Upon arrival, the incident commander noted that nothing out of the ordinary was visible on the exterior of the boat. A crew was sent to the interior of the boat to investigate. The boat was powered by diesel engines and there were no compressed gas cylinders on board.

After further investigation, it became apparent that the explosion had come from the battery compartment in the hull of the boat. The responders concluded that one of the batteries had been giving off hydrogen gas, which gradually built up inside the compartment. Since the compartment was not vented, the gas had nowhere to go. It found an ignition source (possibly a view more

Overview: A hydrogen leak and explosion occurred due to the installation of an incorrectly sized gasket at the suction line of a hydrogen compressor in a refinery hydrodesulfurization plant. The incorrectly sized gasket was mounted during the startup of the plant in 2001 and had never being inspected nor replaced.

Incident synopsis: The operating conditions were stable when the operator received an alarm indicating pressure loss in the circuit. He immediately instructed his field personnel to inspect the area. The hydrogen leak was confined inside the compressor room because the walls and roof were not provided with ventilation devices. An explosion occurred, causing two fatalities and the destruction of the compressor room and some of the surrounding area.

A steel tube with inner diameter of 6 mm and 10 m length was filled with radiolysis gas (stoichiometric H2-O2 mixture) at 70 bar for boiling water reactor simulations. Via a pneumatic valve, a venting line with similar cross-section and 2 m length, filled with atmospheric air, was connected.

For venting the tube, the valve was opened (fast) and an explosion occurred.

Explanation: Due to diffusion ignition in the leading shock, a flame flashed back into the pre-mixed reservoir and induced a detonation there. The tube system and involved measurement technique was destroyed. For safety reasons, the whole installation was set up in a protective container so that no person or other equipment was threatened.

An explosion occurred at a chemical plant in an analysis room containing various analyzer instruments, including a gas chromatograph supplied with hydrogen. A contract operator was performing work to install a new vent line to a benzene analyzer that was part of a group of CO2 analyzers, but separate and unrelated to the gas chromatograph. During the process of this work, a plant supervisor accompanying the contract operator doing the work had an indication of flammable gas present on a portable detector. This was in conflict with the fixed gas detector in the analysis room that was indicating that no flammable gas was present. As a precaution, the plant supervisor immediately cut off the hydrogen supply and, along with the contract operator, began the normal task of determining if view more

Incident Synopsis
During a standard testing procedure, a 3,000 psig relief valve actuated at normal line pressure, releasing gaseous H2. The gaseous H2 combined with air, resulting in an explosion which damaged the test facility.

Cause
The relief valve was improperly set to open at line pressure, and the inspection was inadequate in that it didn't identify this error. Contributing cause was poor design of the venting system, which was installed in a horizontal position, causing inadequate venting and buildup of static electricity.