Tuesday, January 17, 2012

Costa Concordia: The rules of evacuating a ship

Costa Concordia: The rules of evacuating a ship

Costa Concordia
It's been suggested women and children were not given priority for lifeboats when the Costa Concordia capsized. But are there rules governing who leaves a sinking ship first?
It's a famous moment in the Titanic story. "Women and children first!" went the cry.
It's too early to know exactly what happened in the final hours of the Costa Concordia. The captain has already had to deny allegations he left the ship before everyone had been evacuated.
And it has been reported that some male passengers ignored informal injunctions to wait until women and children had made it into the lifeboats.

How did the priority rule begin?

  • This protocol started when HMS Birkenhead sank in 1852
  • "Women and children first" phrase coined in 1860
  • RMS Titanic disaster in 1912 popularised the rule
  • Only 20% of men on board Titanic were saved
  • It is not a part of international maritime law
Edwin Gurd, a retired police chief, told the Times. "We were keen for women and children to go first, and men if they had babies or families. A lot of men regardless of that were trying to save themselves."
But is the traditional maxim of women and children going first really part of the maritime rules?
Once passengers board a cruise ship, they are assigned a lifeboat according to where their cabin is, says Rob Ashdown, operations director at the European Cruise Council.
If there is an accident, as is the case with the Concordia hitting the rocks, it is up to the captain to decide whether to abandon ship. To signal the start of an evacuation, a loud alarm sounds ordering people to go to their muster station.

Costa sinking: How it happened

Infographic of the Costa Concordia
From this point onwards, ships have 30 minutes to load, launch and manoeuvre away the lifeboats, under regulations set down by the International Maritime Organisation. And there is no legal duty to allow women and children to board first, Ashdown says.
The evacuation of the troop ship HMS Birkenhead in 1852 is widely believed to be the first occasion of women and children being told to board the lifeboats first.
The ship was carrying nearly 500 troops and about 26 women and children. After the commanding officer's order for the soldiers to wait, all the women and children survived but most of the men died. The phrase "women and children first" is thought to have come later.
But there is one group who may receive preferential treatment today - disabled people with special mobility needs, Ashdown says.
"This idea of women and children first is just a convention there is for historical reasons," he suggests. "It may be appropriate in certain circumstances and cultures and not elsewhere."
When it comes to air travel, the point is immaterial as prioritising women and children in an evacuation would be impractical.
An argument could be made in relation to ships that men are generally likely to be stronger swimmers than women and therefore have a better chance of survival in the water. But today the argument is less about survival chances and more about treating people fairly.
Prof Ed Galea, an evacuation expert at the University of Greenwich, says orderly behaviour among passengers is crucial to a successful evacuation.
Loss of life headlines The women and children first rule caused more men to die when the Titanic sank
And having studied major disaster situations, including interviewing survivors from the World Trade Center, he says that people don't respond to these evacuations in the way that one might think.
"It's not like Hollywood, it's not like every man for himself. People behave quite selflessly. You'll find people screaming and crying but it doesn't mean they are panicking."
Usually people will help the most vulnerable to leave the scene first. It's not necessarily women, but is likely to be the injured, elderly and young children, he says.
It's too early to know in detail what happened during the Concordia evacuation. But it seems that the crew did an "exemplary" job and that most passengers behaved well, Galea says.
The real problem aboard the Concordia was the slowness of the order to "abandon ship", he argues. Crucial minutes were lost after the ship hit the rocks and reports suggest it was only once the ship began to heel that the evacuation began.
Once a ship heels at 20 degrees it becomes difficult to launch the lifeboats and after the Concordia began to tip over it was soon heeling dramatically.
"They had time," Galea says. "But as I understand it the evacuation didn't start until the ship had a serious heel."

Aye aye 'heats up' middle finger

Aye aye 'heats up' middle finger

The aye aye's cold finger shows up black on thermal images (c) G Moritz / N Dominy Cold finger: the special digit shows up black on thermal images
Madagascar's mysterious aye aye warms up its extra-long finger when searching for dinner, scientists have found.
The lemur, the world's largest nocturnal primate, taps its specialised middle finger on tree trunks to find nutritious beetle larvae.
Studying thermal images, researchers found that the digit was colder than the others but warmed by up to 6C during foraging.
Scientists suggest that the aye aye saves energy by keeping the digit cool.
The findings are published in the International Journal of Primatology.

FINGER FACTS

The aye aye has a delicate middle digit (c) David Haring
  • The aye aye's middle finger is long and very thin - less than half the width of its other digits
  • It has a ball and socket joint so it is far more flexible when it comes to extracting grubs from trees
  • The finger is also used for grooming, scraping out coconuts and drinking. The animal uses it to move water or nectar rapidly into its mouth
The team from Dartmouth University in New Hampshire, US, wanted to investigate the surface temperature of sensitive structures.
The aye aye's unusual middle finger has already been found to be super-sensitive to vibrations, so provided the perfect subject for their study.
"It was striking to see how much cooler the third digit was while not in use and how quickly it warmed to [match] the other digits when engaged in an active foraging task," said graduate student Gillian Moritz, who carried out the study under the guidance of her supervisor, Dr Nathaniel Dominy.
Black and white When not in use, the finger appeared black on thermal images. This indicated a large difference in temperature between it and the white (hot) ears and eyes.
But when the animal was looking for food, the finger rose in temperature by up to 6C.
The finger is hot as it probes a boiled egg (c) G Moritz / N Dominy The finger heats up as it probes a food source
"We think the relatively cooler temperatures of the digit when not in use could be related to its [long, thin] form," said Ms Moritz.
"This form results in a relatively high surface-to-volume ratio [but] such a ratio is bad for retaining heat."
In order to sense the vibrations of beetle larvae through the bark of a tree, the finger is "packed with sensitive nerve endings", the scientist explained.
Because of its specialist sense receptors, using this tapping tool is very costly in terms of energy.
"Like any delicate instrument, it is probably best deactivated when not in use," Ms Moritz told BBC Nature.
Kink in the flow The question of how the lemur controls the heat of a single digit remains unclear.
Ms Moritz suggested two explanations. The first was simply that the blood vessels that supplied the digit could be constricted or dilated.
The second more unusual possibility, she said, was that the creature might employ temperature control method that was linked to the flexibility of its finger.
Ms Moritz explained: "Because the finger is fragile and vulnerable to injury, it is often extended back and out of the way during locomotion and periods of inactivity," she said.
This extension could cause a "kink" in the artery that supplies warm blood to the digit.

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Like any delicate instrument, it is probably best deactivated when not in use”
Gillian Moritz Dartmouth University
In the same way a bent garden hose supplies less water, the artery could supply less blood, keeping the finger much colder than its fully supplied neighbouring digits.
Aye ayes are the only primates known to have this strange adaptation.
The species is listed as Near Threatened by the International Union for Conservation of Nature (IUCN), mainly because of threats to its habitat.
But the odd-looking primate also suffers direct persecution. Superstition in Madagascar describes the species as a bad omen. Those that are pointed at by the creature's mysterious finger are said to meet their death.