The single hull oil product tanker was in ballast with no cargo on board
lying at the anchorage of a West African port.
An Able Seaman and an Ordinary Seaman were employed in cleaning No. 1 Centre Tank;
at the same time a Deck Fitter and another Ordinary Seaman were working
on the catwalk to repair the rail on the catwalk.
The site of this repair was directly above the Butterworth hatch in No. 1 Centre Tank
and they were equipped with a grinding machine.
This work was ordered by the Chief Officer.
An explosion occurred in No. 1 Centre Tank at 1345 hours (local time).
The two men working in No. 1 Tank were injured and brought to the deck by 1350 by crew
who assembled to assist in dealing with the incident.
The two men who had been working on the catwalk were also injured and given assistance.
All of the injured seamen were given first aid
and then conveyed to hospital for medical treatment.
Later, the two men who had been working in the tank died from their severe burn injuries.
The vessel sustained extensive structural damage.
The explosion was most probably caused by the ignition of pockets of gas in No. 1 Centre Tank
by sparks from grinding work on the catwalk immediately above an open tank cleaning hatch.
The grinding work on the catwalk while tank cleaning was in operation
was in contravention of the procedures laid down in the Safety Manual of the vessel.
The risk of carrying out hot work on tankers is recognized
in the procedures in the Safety Manual which require that:
- Permits are required for all hot work;
- Hot work is not to be carried out while tank cleaning is in progress;
- Procedure for hot work is reviewed by those concerned before beginning.