Life Jackets Are More Important Than Clothes.

Life jacket is a portable life saving tool that can be carried and used for personal use. It can provide buoyancy and buoyancy distribution in case of emergency, so that the drowning person can turn to the head and float on the rescue posture. It is an individual life saving equipment for water, and is widely used in various aquatic activities such as fishing, water pportation, water operations, water sports and other special industries and departments such as Customs Smuggling, army and so on.

The development of individual lifesaving equipment, the structure of lifejackets is diversified. Many lifejackets are no longer worn on the body like clothes, but buoyant components are integrated on mesh vest or other clothes, or hang in the bag in the waist, when used in the neck and so on. Therefore, the connotation and denotation of the concept of life jacket has been separated, and can no longer accurately reflect the structural characteristics of the existing diversified individual life-saving equipment.

The the United State Coast Guard and International Standard Organization call it the personal floating device (Personal Flotation Devices), and the US military specification is called life jacket (Personal), which does not contain the concept of "clothes". The British standard is called lifejackets and buoyancy equipment, but this jacket is actually vest.

As an individual water lifesaving equipment, no matter what type of life jacket, it should have the following performance.

Safe floating performance.

Lifejackets can provide enough buoyancy and reasonable buoyancy distribution, so that the drowning personnel can appear above the water surface in the water, without affecting the safe floating posture of breathing.

Performance.

Lifejackets should provide rescue devices, such as position lights, whistles and other acoustic and light display devices and bright colors; provide rescue and rescue devices such as rescue harness; provide to deal with dangerous substances such as shark agent, and some of the survival of the genus such as fresh water.

Aptamer performance.

Lifejackets must be suitable for body, convenient to carry, and comfortable when they are used for a long time, and do not interfere with other activities of users.

Thermal performance.

For cold waters, lifejackets must have certain thermal insulation properties to avoid death caused by rapid loss of body temperature and excessive body temperature.

In the above four performances, the safety floating performance is the basic performance that each life jacket must have, and the life jacket with different uses has different emphasis on the other three performances.

For example, the coating materials for military life jackets often require fire retardant and flame retardancy. In order to carry weapons, they require high buoyancy and higher requirements for rescue performance.

In addition to safety and floatability, sports life jackets tend to pay more attention to their fitness.

Natural buoyancy life vest

The structure of lifejacket determines buoyancy distribution and aptamer performance, and affects the selection of fittings, buoyancy materials and buoyancy. Different buoyancy materials also require different structures.

At present, there are two types of natural buoyancy life jackets: kapok lifejacket and foam plastic life jacket.

Because kapok and foam plastics are soft materials, they are easy to cut into prefabricated parts. They are often used in vest life jackets with high fitness requirements, also known as lifesaving jackets.

Kapok lifejacket.

Kapok is a flocculent fiber material that provides buoyancy through the fiber's hollow height and interfiber space.

Kapok lifejacket is made of kapok fiber filled in coated fabric.

The usual style is vest style, such as our early life vest 64.

Generally, there are two cysts distributed around the left and right chest, and no buoyancy material behind them.

The waist is equipped with a fixed mediation band, partly equipped with crotch strap or adjusted by shoulder strap.

Foam plastic life vest.

Because of its easy processing performance, low price, excellent closed cell structure and water repellency, foam plastics become the most widely used buoyancy material.

There are fixed belt in the Department, mostly used for life vest, large and low sleeves arc, round neck, adjustable sides, thin shoulder straps, back for buoyancy material, part of the heel can be folded, with good aptamer, most of the sports lifejackets are this kind; the top collar, sleeveless, buoyancy material on front and both sides, buoyancy distribution is divided into different sizes and thickness, so as to increase fitness and reduce buoyancy loss, generally equipped with three to four fixed adjustment belts, some with crotch strap, and a vest type life vest with buoyancy material but partly hollowed out, which is conducive to ventilation and heat dissipation, and is mostly used for homework. The most common type is the vest pattern, with the following structures: small pointed collar, sleeveless, no buoyancy material on the back, waist.

In addition to vest, foam plastic lifesaving clothing also has the following styles: Yoke type, buoyancy material behind neck, front two straight strip, waist fixed adjustment belt, sleeve type, thick foam, front two pieces, collar part, bottom fixed adjustment belt, some in chest and waist, many for passenger ship use; jacket type, with sleeves, bottom and cuff elastic band can be folded, and has warm function.

Inflatable lifejacket

The life jacket provides buoyancy by inflating the hot air bag, and the airbag should have good air tightness.

Inflatable lifejackets usually have the following structures:

Yoke.

The air bag is inverted U shaped in the neck of the user, with a single capsule and a double bag.

The capsule and the capsule of the double pocket yoke life jacket are independent of each other, and are equipped with an inflatable device and an air filling valve respectively.

The yoke life jacket is usually buoyancy free, with buoyancy concentrated on the chest and some buoyancy behind the neck to support the head. It can ensure that the user is safe and floating in the water. In order to avoid the escape of the life jacket from the body, there is an adjustable fastening belt at the waist of the yoke lifejacket. There is also a rope fixed to the back waist or a front pocket with a rope fixed to the front waist. Some lifejackets have one or two crotch bands. For example, the American military MK-46PA parachute life jacket is often equipped with two crotch belts, and the child life vest for aviation is equipped with a crotch strap.

There are two types of yoke lifejackets: one is no collar strip, or even a narrow strip after folding, but the inflatable folding part is still enough buoyancy. It is mainly used for working life jackets. The other is a non collar circular arc. After inflating, the front part of the air bag has a circular arc enlargement, so that the neck position is more suitable for the human body to slip away, and the mouth and nose are not easy to water, and is used for aviation and navigation.

Sleeve type.

Like yoke lifejackets, there are single and double bursts.

The anterior airbag and the chest and waist are inflated, and the chest airbags are rectangular to provide most of the buoyancy. The buoyancy behind the neck is used to support the head.

Because the collar of the collar is less than the head circumference of the human body, the life jacket is not easy to slip away from the human body. In order to fix the anterior chest airbag, it is usually equipped with a waistband to adjust the belt.

The life jacket is generally suitable for the marine environment with complex and harsh conditions, mostly for oceangoing freighters.

There are two ways of placing the life jacket on the head when it is not inflated. One is directly put on the neck. After water, it can inflate the air bag to provide buoyancy by automatic or manual inflation. One is to fold it in a specially made bag and hang it in the waist, and when it is used, it is removed and put on the neck.

Armpit type.

Generally, it is a double capsule structure, with each side of the left and right axillary sac, which is fixed on the human body through the waist belt. Buoyancy is distributed under two armpits, so that the human body is upright and floating in the water, for example, our air force pilots wear lifejackets.

When not inflated, it can be folded under two armpits, small in size and easy to carry.

Vest type.

The yoke type air bag is fixed on the vest, and the vest is replaced by the fabric. The air bag is fixed on the user body and has better wearing comfort.

The life-saving effect is the same as yoke.