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Personal flotation device

technology Maturity 11-13

A life jacket helps you stay afloat.

LifevestlocationSeatbeltreminder.jpg
LifevestlocationSeatbeltreminder.jpg
You wear it in deep water. It keeps your head above the waves. This helps you stay safe. It is a very good tool.
Childs life vest.jpg
Childs life vest.jpg
Do you like to swim in water?

42 words

A life jacket helps you stay afloat.

LifevestlocationSeatbeltreminder.jpg
LifevestlocationSeatbeltreminder.jpg

You wear it in deep water. It keeps your head above the waves. This helps you stay safe.

Childs life vest.jpg
Childs life vest.jpg

These vests can be made of foam. Some use air to float. They can be bright colors like red or yellow. This helps people see you.

Lifejacket2.PNG
Lifejacket2.PNG

Some vests have straps. These straps keep the vest in place. They stop the vest from sliding up. A flap can also help hold your head up.

Life jackets are used on boats and planes. They help you if you fall in. They are great tools for water safety.

105 words

A personal flotation device is often called a PFD.

LifevestlocationSeatbeltreminder.jpg
LifevestlocationSeatbeltreminder.jpg
It can also be called a life jacket or life vest. These tools help keep you afloat in deep water. They keep your head and mouth above the waves. This is important even if you are not awake.
Childs life vest.jpg
Childs life vest.jpg

People wear PFDs on boats, planes, and while swimming. Many are made of foam. Some use air to float. These air vests can be blown up by mouth. They can also use a small tank of gas.

Alaska 2007 075.jpg
Alaska 2007 075.jpg
Most PFDs are bright colors like red or yellow. This makes them easy to see. Some have special tape that shines in the dark. This helps rescuers find you at night.

There are different kinds of PFDs. A buoyancy aid uses foam to help you move easily.

Lifejacket2.PNG
Lifejacket2.PNG
These often have straps. The straps stop the vest from sliding up your neck. Some have a flap to help hold your head up.
AREA 47 Rafting Imster Schlucht, 2018 (cropped).jpg
AREA 47 Rafting Imster Schlucht, 2018 (cropped).jpg
Other types include survival suits. These are full-body suits that protect you from cold water.

185 words

A personal flotation device, or PFD, is a very important tool for staying safe.

LifevestlocationSeatbeltreminder.jpg
LifevestlocationSeatbeltreminder.jpg
People often call them life jackets, life vests, or life preservers. Their main job is to keep a person afloat in deep water. A good PFD keeps your head and mouth above the surface. This means you do not have to swim to stay up. It can even keep you afloat if you are unconscious.
Childs life vest.jpg
Childs life vest.jpg
People wear them on small boats or while swimming. They are also found on large ships for emergencies.

Most PFDs work using one of two main ways. Many are made of foam pieces that naturally float. These are often called buoyancy aids.

Lifejacket2.PNG
Lifejacket2.PNG
Other types use air to stay afloat. Some life jackets have air cells called bladders. You can inflate these by blowing into a tube. You can also use a small canister of gas to fill them.
Alaska 2007 075.jpg
Alaska 2007 075.jpg
These devices are often bright yellow or red. This makes them easy for rescuers to see. Some even have special tape that shines when light hits it.
French bulldog in life jacket.jpg
French bulldog in life jacket.jpg

Humans have used many things to float for a long time. Early people used animal skins or hollow gourds to cross rivers. In 1802, Abraham Bosquet suggested using canvas bags filled with cork shavings.

PSM V31 D669 Cork jacket and life buoy.jpg
PSM V31 D669 Cork jacket and life buoy.jpg
Later, in 1854, Captain John Ross Ward created a cork vest. He worked for the Royal National Lifeboat Institution in the UK. He wanted to protect lifeboat crews from bad weather and drowning. In 1900, Gustave Trouvé even patented a lifejacket that used batteries. It could power a light to send SOS messages.

Many different designs have been made for specific jobs. During World War II, many people used kapok suits. Kapok is a soft material from a vegetable.

Men donning kapok suits on ship delivering oil to Allies during WWII (23558647890).jpg
Men donning kapok suits on ship delivering oil to Allies during WWII (23558647890).jpg
In 1928, Peter Markus invented an inflatable life preserver. People called it a "Mae West" after a famous actress.
Mae West life preserver.jpg
Mae West life preserver.jpg
These were very popular with pilots in the war. In 1972, people began using synthetic foam instead of kapok. These modern jackets are very strong and reliable.

PFDs are designed to fit many different people and activities. They come in different sizes to match a person's weight.

AREA 47 Rafting Imster Schlucht, 2018 (cropped).jpg
AREA 47 Rafting Imster Schlucht, 2018 (cropped).jpg
Some are made for fun activities like water skiing. Others are specialized for scuba diving or even submarines. Some even have extra parts to keep you warm in cold water. This helps prevent a person from getting too cold. Whether you are on a raft or a plane, these tools help keep you safe.

452 words

A personal flotation device, or PFD, is a specialized piece of equipment designed to prevent drowning.

LifevestlocationSeatbeltreminder.jpg
LifevestlocationSeatbeltreminder.jpg
These devices are known by many names, including life jackets, life vests, and buoyancy aids. Their primary function is to keep a wearer afloat in a body of water. A successful PFD keeps the user's head and mouth above the surface. This allows a person to stay afloat without needing to swim or tread water. Most importantly, a PFD can keep a person afloat even if they are unconscious.
Life vest.jpg
Life vest.jpg

Most PFDs function through the principle of buoyancy. Many are constructed from foam pieces that naturally float in water. Others use air chambers, also called bladders, to provide lift. On airplanes, these bladders are often inflated using a canister of carbon dioxide gas. A person can also inflate these cells orally by blowing into a flexible tube. This tube includes a one-way valve to seal the air inside the bladder.

Alaska 2007 075.jpg
Alaska 2007 075.jpg
Some specialized designs use a combination of both foam and air chambers.

There are three main categories of PFDs: life jackets, buoyancy aids, and survival suits. Buoyancy aids are often made with a foam core to allow for freedom of movement. They are common in sports like rafting because they are inexpensive and require little maintenance. These often include adjustable understraps to prevent the vest from riding up. They may also feature a headrest flap and a grab handle for rescuers. Life jackets and survival suits provide different levels of protection depending on the environment.

Humanity's attempt to stay afloat has evolved significantly over centuries. Early people used inflated animal skins or hollow gourds to cross deep rivers. In 1802, Abraham Bosquet proposed using canvas bags filled with cork shavings.

PSM V31 D669 Cork jacket and life buoy.jpg
PSM V31 D669 Cork jacket and life buoy.jpg
By 1854, Captain John Ross Ward created a cork vest for lifeboat crews. This design provided both buoyancy and protection from harsh weather. In 1900, Gustave Trouvé patented a battery-powered lifejacket. This advanced version could power a light to transmit SOS messages and launch flares.

Material science has changed how PFDs are built. In 1904, hard cork was replaced by pouches filled with kapok. Kapok is a soft, vegetable material that made life jackets more flexible. During World War II, many sailors wore these kapok suits. In 1972, synthetic Beaufort foam became the standard for inherently buoyant jackets. Unlike inflatable models, these foam jackets do not rely on air to function. They are highly reliable and can even support both a rescuer and a rescued person at once.

Some PFDs are famous for their unique histories and names. In 1928, Peter Markus invented an inflatable life preserver.

Mae West life preserver.jpg
Mae West life preserver.jpg
During World War II, airmen nicknamed these "Mae Wests" after a famous actress. This name came from how the inflated vest changed the wearer's appearance. These devices were vital for pilots, such as Eric Brown, who survived a carrier sinking.
The Fleet Air Arm during the Second World War TR1121.jpg
The Fleet Air Arm during the Second World War TR1121.jpg
Other specialized gear includes the UVic Thermo Float, which uses neoprene rubber to protect against hypothermia.

Design and regulation ensure that PFDs meet specific safety needs. Civilian devices for recreational boaters differ from military models. Military PFDs may include ballistic nylon to protect air canisters from gunfire. They must also be compatible with other gear like parachute or rappelling harnesses.

Childs life vest.jpg
Childs life vest.jpg
For visibility, many PFDs are bright orange or yellow. They often feature retroreflective "SOLAS" tape. This tape helps searchlights spot a person in the dark. In the United States, federal laws require children under age 13 to wear a PFD in watercraft.

628 words
🖼️ Images & Media (12)
File:PSM V31 D669 Cork jacket and life buoy.jpg
PSM V31 D669 Cork jacket and life buoy.jpg
File:Men donning kapok suits on ship delivering oil to Allies during WWII (23558647890).jpg
Men donning kapok suits on ship...
File:The Fleet Air Arm during the Second World War TR1121.jpg
The Fleet Air Arm during the Second World...
File:Mae West life preserver.jpg
Mae West life preserver.jpg
File:LifevestlocationSeatbeltreminder.jpg
LifevestlocationSeatbeltreminder.jpg
File:AREA 47 Rafting Imster Schlucht, 2018 (cropped).jpg
AREA 47 Rafting Imster Schlucht, 2018...
File:Lifejacket2.PNG
Lifejacket2.PNG
File:Childs life vest.jpg
Childs life vest.jpg
File:Life vest.jpg
Life vest.jpg
File:Alaska 2007 075.jpg
Alaska 2007 075.jpg
File:Survival suit mg 6520.jpg
Survival suit mg 6520.jpg
File:French bulldog in life jacket.jpg
French bulldog in life jacket.jpg
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