Communication and English Chemical tanker Bow Mariner, 2004

The officers gave orders. The crew did not understand why. The ship exploded.

On 28 February 2004 the chemical tanker Bow Mariner exploded and sank off Virginia while the crew was cleaning cargo tanks that had carried a flammable chemical. 21 of the 27 people on board died.

Words in this case

tank cleaning: Washing cargo tanks after discharge.
flammable vapour: Gas from a cargo that can ignite; measured before any tank is opened.
inerting: Filling a tank with gas low in oxygen so the vapour cannot burn.
toolbox talk: The briefing before a job: what, how, what can go wrong.
ignition source: Anything that can light a vapour: a spark, a flame, static electricity.

More words like these in the glossary and in listening practice.

What happened

Bow Mariner was on a coastal voyage after discharging a cargo of MTBE, a volatile, flammable additive for petrol. The senior officers ordered the crew to open the hatches of the empty tanks and start cleaning them, without inerting the tanks and with the residues still giving off flammable vapour. Vapour spread over the deck and into the tanks; something ignited it, and the ship blew up.

The ship sank within about an hour. Six crew survived in the cold water; 21 died, including most of the officers. The United States Coast Guard investigated because the ship sank in US waters.

The report found the immediate cause in the tank cleaning: opening the tanks of a flammable cargo without inerting or gas-freeing them, contrary to the ship's own procedures. Behind it the investigators found a ship on which the Greek senior officers and the Filipino ratings and junior officers did not communicate: the crew was not told what the cargo was, what the hazards were or why the procedures existed, was not properly trained on the ship, and followed orders it did not understand. Drills had not prepared the crew to abandon ship in the dark.

Why it happened

Cargo tanks that had carried a flammable chemical were opened for cleaning without being inerted or gas-freed.
The officers did not share information with the crew: the crew did not know the cargo, its hazards or the reasons for the procedures.
A culture of orders without explanation across a language and nationality divide, and training that existed on paper.
The abandon ship was chaotic; most of the crew did not get into survival craft.

What to remember on board

Before a cargo operation or tank cleaning, a toolbox talk tells everybody what the cargo is, what can go wrong and what the checks are, in the working language.
On a tanker nobody opens a tank of a flammable cargo without a gas reading and the procedure in front of them; a rating who is told to do it may say "please explain" and must be answered.
Multinational crews work when the officers talk to the crew and check understanding, not when they issue orders in short words and walk away.
Abandon ship drills are done for real conditions: at night, with immersion suits, with the boats and rafts you will actually use.

What changed afterwards

The report reinforced the ISM Code's demand that crews be trained and informed on the ship they serve, and became a standard teaching case on communication across nationalities on tankers.

Three questions

The kind of questions a knowledge test asks about this case. Keys 1 to 4 answer, Enter goes on.

Source: Investigation into the explosion and sinking of the chemical tanker Bow Mariner in the Atlantic Ocean on 28 February 2004, United States Coast Guard, 2005.

On this site: Oil and chemical tankers · Working English on board.

Plain-English summary of an official investigation report. Facts and findings are the investigators'; the wording is ours. Nothing here is legal advice or a substitute for the report itself.