Lifejacket

A personal flotation device (abbreviated as PFD; also referred to as a life jacket, life preserver, life belt, Mae West, life vest, life saver, cork jacket, buoyancy aid or flotation suit) is a piece of equipment designed to assist a wearer to keep afloat in water. The wearer may be either conscious or unconscious.

PFDs are available in different sizes to accommodate variations in body weight. Designs differ depending on wearing convenience and level of protection.

The most ancient examples of primitive life jackets can be traced back to inflated bladders of animal skins or hollow, sealed gourds, for support when crossing deep streams and rivers. Purpose-designed buoyant safety devices consisting of simple blocks of wood or cork were used by Norwegian seamen.

In 1804 a cork life jacket was available for sale. The Sporting Magazine October, 1804, Vol.XXV, No.147, Page 129. MALLISON's SEAMAN'S FRIEND.

Personal flotation devices were not part of the equipment issued to naval sailors until the early 19th century, for example at the Napoleonic Battle of Trafalgar, although seamen who were press-ganged into naval service might have used such devices to jump ship and swim to freedom.

It was not until lifesaving services were formed that the personal safety of boat crews heading out in pulling boats in generally horrific sea conditions was addressed. The modern life jacket is generally credited to one Captain Ward, a Royal National Lifeboat Institution inspector in the United Kingdom, who created a cork vest in 1854 to be worn by lifeboat crews for both weather protection and buoyancy.

In 1900, French electrical engineer, Gustave Trouvé, patented a battery-powered wearable lifejacket. It incorporated small, rubber-insulated maritime electric batteries not only to inflate the jacket, but also to power a light to transmit and receive SOS messages and to launch a distress flare.

The rigid cork material eventually came to be supplanted by pouches containing watertight cells filled with kapok, a vegetable material. These soft cells were much more flexible and comfortable to wear compared with devices utilizing hard cork pieces. Kapok buoyancy was used in many navies fighting in World War II. Foam eventually supplanted kapok for 'inherently buoyant' (vs. inflated and therefore not inherently buoyant) flotation.

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Wikipedia