A petroleum refinery experienced a catastrophic rupture at one bank of three heat exchangers in a catalytic reformer/naphtha hydrotreater unit because of high temperature hydrogen attack (HTHA). Hydrogen and naphtha at more than 500F were released from the ruptured heat exchanger and ignited, causing an explosion and an intense fire burned for more than three hours.

The rupture fatally injured seven employees working in the immediate vicinity of heat exchanger at the time of the incident. The workers were in the final stages of a start-up activity to put a parallel bank of three heat exchangers back in service following cleaning. Such start-up activities had resulted in frequent leaks and occasional fires in the past and should have been considered as hazardous and nonroutine. 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 laboratory technician died and three others were injured when hydrogen gas being used in experiments leaked and ignited a flash fire.

The incident occurred in a 5,700-square-foot, single-story building of unprotected non-combustible construction. The building was not equipped with automatic gas detection or fire suppression systems.

Employees in the laboratory were conducting high-pressure, high-temperature experiments with animal and vegetable oils in a catalytic cracker under a gas blanket. They were using a liquefied petroleum gas burner to supply heat in the process.

Investigators believe that a large volume of hydrogen leaked into the room through a pump seal or a pipe union, spread throughout the laboratory, and ignited after coming into contact with the view more

SummaryA fire occurred in a battery manufacturing plant that was about to cease operations for the night. The fire caused an estimated $2.4 million in property damage when an electrical source ignited combustible hydrogen vapors.BackgroundThe incident occurred in the forming room, where wet cell batteries were stored for charging on metal racks. The facility had a wet-pipe sprinkler system, but no automatic hydrogen detection equipment.Incident SynopsisAt 11:52 pm, a security guard on patrol noticed a free burning fire in the forming room and notified the fire department. It took fire fighters almost three hours to bring the fire under control.Although the facility was equipped with a wet-pipe sprinkler system, the forming room's branch had been disconnected 10 to 15 years before 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.