Concerned that heavier occupants might cause commercial vessels to capsize or sink, US Coast Guard officials have added 12kg to the weight of the "average" person used to calculate how many people a ship is licensed to carry.
In the past, stability tests have worked on the basis that the average man, woman or child who sets foot on board would weigh 72kg.
Under the new rules, that has jumped to the more robust figure of 84kg.
