The Australian Transport Safety Bureau (ATSB) completed a
series of investigations into an incident that occurred on
25 January 2022 during the use of the gas combustion unit
(GCU) on board the pilot demonstration vessel "Suiso
Frontier" berthed at the Port of Hastings, Australia. The
final report was released on 2 February 2023.
The final report concludes that one of the two air fan
discharge dampers in the GCU closed due to the failure of
the solenoid valve that controls the damper. The cause of
this solenoid valve failure was that the incorrect type of
solenoid valve was installed during manufacturing. As a
result, the air supply to the GCU stopped, and the hydrogen
flame, which had been burning normally, became unstable, and
the flame propagated out the unit’s chimney (the vent stack)
on the deck of the ship, as expected. The ATSB report also
mentions that the GCU needs to be equipped to detect whether
the dampers are open or closed.
As reported in the previous report (https://www.hystra.or.jp/en/gallery/article.html#news07),
when the onboard operator saw the light and smoke from this
vent stack for a few seconds, the GCU was immediately and
safely shut down manually, causing no human, equipment or
environmental damage.
In parallel with the ATSB investigation, HySTRA replaced the
solenoid valve that caused the malfunction with a new valve
according to the unit’s specifications, and the GCU control
system logic has been programmed with added safety
parameters which will automatically shut down the GCU if a
similar fault is detected. To date, HySTRA has confirmed
these modifications satisfy the safety measures recommended
by the ATSB in its final report and also once again
confirmed the quality control system with all relevant
parties in order to prevent recurrence of the problem.
HySTRA continues to focus on safety as it delivers hydrogen
energy supply chains.
For the ATSB's final investigation report (English), please
visit the ATSB website at
https://www.atsb.gov.au/publications/investigation_reports/2022/mair/mo-2022-001