The sensing diaphragm of a pressure transducer (PT), as supplied on an outdoor hydrogen compressor, unexpectedly ruptured and released approximately 0.1 kilograms hydrogen to atmosphere from the compressor discharge line. At time of incident, personnel nearby were alerted by a loud 'pop' and dust disturbance. Simultaneously, the facility monitoring system detected loss of the PT signal and initiated equipment shutdown. Facility personnel then closed isolation hand valves to stop the leak, locked and tagged out the equipment, and restricted the area. The failed component, a cigar type PT rated to 20,000 psi, originally supplied and installed by the manufacturer as part of the compressor package, was removed and inspected. Inspection revealed severed wires, a view more

The malfunctioning of the non-return valve of the hydrogen compressor caused the pressure between the hydrogen bottle and the compressor to rise up to the maximum allowed pressure of 275 barg. As a consequence, as foreseen by the safety system, the rupture disk of the safety valve broke and the hydrogen content of the gas bottle and the pipe section involved was released on top of the building. The flame was seen for a very short period by a guard, and could have been caused by the following series of events:

Expansion of hydrogen at the end of the exhaust pipe.
Consequent mixing of hydrogen and air up to a near-stoichiometric mixture and increase of gas temperature.
Mixture ignition due to sparks from static electricity generated by gas molecule friction against view more

The sensing diaphragm of a pressure transducer (PT), as supplied on an outdoor hydrogen compressor, unexpectedly ruptured and released approximately 0.1 kilograms hydrogen to atmosphere from the compressor discharge line. At time of incident, personnel nearby were alerted by a loud 'pop' and dust disturbance. Simultaneously, the facility monitoring system detected loss of the PT signal and initiated equipment shutdown. Facility personnel then closed isolation hand valves to stop the leak, locked and tagged out the equipment, and restricted the area. The failed component, a cigar type PT rated to 20,000 psi, originally supplied and installed by the manufacturer as part of the compressor package, was removed and inspected. Inspection revealed severed wires, a separated wire housing, view more