Life Jackets - The Science Behind How They Work

Life Jackets – The Science Behind How They Work

A life jacket is the most important pieces of equipment to have when you're swimming. They come in either vinyl or nylon material that helps the life jacket stay afloat. In this short post, we want to show you how those jackets work.

Our main goal is to teach you the basic concepts of buoyancy; then we'll describe how your jackets stay afloat while submerged in the water. Lastly, we'll show the three main types of life vests, so you'll know which one supports your needs the most.

Buoyancy Basics.

Understanding Density

Density is the first principle that explains why everything floats. Density is also known as how much matter is placed within a specific volume of space. For example, lead has more density than iron because lead ingots weigh more than iron ingots.

Buoyancy Basics

The main reason why your life jacket stays afloat is due to a concept called buoyancy. If an object is less dense than the water it's submerged in, it will begin to float to the water. For example, oil can float on the surface of water due to its low density.

Oil can float on the surface of water due to its low density.

Wood also floats because of the resins and the wood fibers trap the air. As a result, the wood's average density is decreased making it easier for it to stay afloat.

Having a life vest will save your life if you get stuck in the middle of an ocean. This is because the vest will keep you buoyant and allows you to remain above the water instead of being pulled down by the water pressure.

How Do Life Jackets Float

Life Jackets can float because they are made of buoyant materials, but it isn't enough to keep the user fully afloat.

Your jacket must be designed to have a lot of lift so that the jacket being worn doesn't lower the buoyancy of wearer or the jacket itself. This saves you and your jacket from sinking underwater, and it works to keep your body buoyant.

The material inside your life jacket traps air to help keep you afloat. It traps in the air when your jacket is submerged underwater. The trapped air weighs less than the water. As a result, the water pushes up more than the jacket pushing down. This allows your jacket to float and remain buoyant and can hold up extra weight without sinking.

Buoyancy Aid Float Life Vest

Life jackets are categorized and measured based on how much extra weight it can support. Adult jackets usually have a buoyancy range from 15 pounds to 22 pounds. Because the average person needs about 7 to 12 pounds of buoyancy to stay afloat, your life jacket doesn't have to support your whole body weight.

Instead, the life jacket supports that seven to 12 pounds, with a few extra pounds to spare. You can place an item that weighs less than the minimum buoyancy offered by the life jacket, and your jacket will hold the item without it sinking.

Types Of Life Vests

Historically, balsa wood, cork, and kapok (inherently buoyant material that's from a tropical tree that's also used for insulation and a mattress). Today, materials such as plastic foams are used to

Buoyancy Aid Float Life Vest

To understand buoyancy, you need to know the different life vest types. Here is a quick table displaying the different types of life vests that are available:

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    Foam life jackets can float because their plastic foam traps micro air bubbles. This increases the overall buoyancy in the same fashion as wood. Foam jackets are inherently buoyant because you don't have to do anything to activate its flotation.- 
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    Inflatable life jackets are filled with carbon dioxide or air. It's powered by a small cartridge of compressed gas that's only activated when emergencies arise. Jackets that are fueled by carbon dioxide or air. Both carbon dioxide and the air is less dense than water, making them have move mobility and extra lift.
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    Hybrid life jackets are a mixture of manual inflation and natural buoyancy. No matter how the trapped air gets in the vest, you'll weigh much less than the displaced water, and it will hold you afloat in a body of water.

It doesn't matter which one you buy, each of the life vests is designed to protect you when your body comes in contact with the water. By getting an inflatable life vest, you increase the chances of survival when your ship collapses and you're unable to swim back to shore.

Closing Thoughts

Overall, you need to look into a life vest. They are reliable and inexpensive tools that provide enough buoyancy to keep your body floating in the water. Conclusively, we suggest that everyone keeps a life vest nearby the next time they enter a boat. Doing so will save your life and the others around you.

family wearing a life vest

Do you have any questions regarding life vests?

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