Specification :

Lifejackets or life vests are mandatory on airplanes travelling over water ( in which case they consist of a pair of air cells ( bladders) that can be inflated by triggering the release of carbon dioxide gas from a canister— one canister for each separate cell. Or the cells can be inflated " orally" that is by blowing into a flexible tube with a one-way valve to seal the air in the cell) . Lifejackets must also be supplied on commercial seafaring vessels, accessible to all crew and passengers and to be donned in an emergency. Not only people wear any type of personal flotation devices, but some are available for dogs to wear.