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Precis File
source Static Electric Discharge Hazard On Bulk Oil Tank Vessels, Phase 1 Report, Michael G. Dyer, DTS-73, Volpe National Transportation Systems Center
type A
dead 1

3.1 FIONA (31 August 1988)
The forward cargo tank of the FIONA exploded while a surveyor measured cargo temperature prior to unloading, resulting in one death. The National Transportation Safety Board (NTSB) concluded that a steam leak in the tank caused static charge to be generated, that the charge accumulated on an ungrounded temperature probe and discharged as the probe was withdrawn from the tank, and that the resulting sparks ignited explosive vapors from the residue of the tank's previous cargo.

NTSB's recommendations addressed the foregoing items and other contributory factors:

FIONA's cargo tanks should have been inerted, and the ISGOTT should state more clearly that the inert gas system (IGS) should be used with all cargoes unless tanks are gas free.

The main source of the explosive vapors was contamination of the cargo (No. 6 fuel oil) by previous condensate cargo, while release of light hydrocarbons by the No. 6 fuel oil may have been contributory. Masters of vessels carrying Grade E cargoes should certify that explosive vapors are not present prior to sampling or measuring cargoes with a combustible gas indicator device.

The static charge was generated by a steam leak in the cargo heating pipes and accumulated on an ungrounded temperature probe. Better maintenance might have prevented the casualty. The probe lacked a precautionary nameplate stating the, need for grounding the instrument during use. Underwriters Laboratory UL) should adopt the Canadian Standards Association requirement for such a nameplate. The internal grounding wiring on these probes should also be checked periodically.

source CTXK
type C
material F
dead 1

Sounds like tank was not inerted which is incredible in 1988. ISGOTT cannot be more clear than it already is.

There is a ship called Fiona, IMO Number 5240851, but this ship was built in 1957, so unlikely to be the right vsl. The NTSB Report is Mar 89-03, NTIS Number PB89-916403 but CTX has not yet seen.