Rodent caused short circuiting of 440v bus bar

What happened?

A fire alarm was traced to the emergency generator room. A rodent had found its way into an emergency switchboard cabinet, causing a 440V short circuit, sparks and a foul smell. The board was isolated and the dead rat was removed.

What went wrong? What were the causes?

This appears to be an isolated incident wherein the rodent had come on board during port stay, and gained access to the emergency generator room when the door was opened during routine weekly testing. The vessel crew had not experienced the presence of rodents in recent months. There was no evidence (rat droppings) found anywhere on deck, in the accommodation or in the provision stores. All the doors to accommodation and hatches were kept closed at all times. Rat traps were in place at various locations.

What actions were taken? What lessons were learned?

• The vessel was thoroughly searched for rodents in accommodation, the stores and on the deck after the incident; nothing was found;
• Rat traps remained in place on deck and in accommodation and stores, and the baits renewed;
• During port stay, rat guards were to be used on moorings;
• During the loading of provisions/cargo, crew were to be extra vigilant for presence of rodents.

This incident appears to be unique in the IMCA safety flash database and for that reason is passed onto members.