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Lifejackets
Nowadays there are many different types of lifejacket, and finding your way to the model which best suits your needs isn’t easy.
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Lifejackets versus Buoyancy aids
Generally speaking a buoyancy aid is a jacket which may or may not support the full weight of its wearer, and may or may not turn the wearer face-up if unconscious. A
lifejacket should support the full weight of the wearer, and should turn the wearer face-up if unconscious.
A buoyancy should not be considered as a true safety device. The one possible exception is for children under five years old, where the buoyancy aid is capable of supporting
the child’s entire weight and it incorporates a collar to turn the child face-up. A buoyancy aid may be less bulky than a lifejacket which could be easily damaged. At least one true
lifejacket should always be carried for each crew member and spares are highly recommended for long voyages.
Foam Lifejackets
These are the good old-fashioned lifejackets that you still see on passenger ferries. They remain the most reliable lifejackets on the market, but are big and clumsy, and
difficult to store. They are also not very comfortable to wear at all times. They are however a must for small children, if you want full lifejacket status, as there is no risk of
deflation, or setting them off accidentally.
Gas Inflatable Lifejackets
These lifejackets are essentially inflatable bladders which are stored in a folded state, usually around the neck. They can all be manually inflated by blowing through a
tube, or by pulling a tag. Some can automatically inflate when in contact with water. There are various different types of gas inflatable lifejacket and it is very important to
appreciate the various differences.
Bladder Packaging
The bladder is normally packed around the neck. It can either be totally enclosed within a protective casing (We’ll call this type A) or part of the bladder is reinforced
and folded to form a protective case (Type B). A third type of lifejacket (Type C) folds into a pouch that can be worn around the waist.
A type A bladder is far better protected from both tearing and UV rays. It is also easier to store extra equipment such as lights and hoods within a type A jacket.
They can be secured around the outside by either a zip or Velcro. A zip is likely to last longer if well looked after.
A type B is generally lighter, cheaper and often more comfortable to wear, although the way that they are usually folded tends to rub against the back of the neck.
A type C lifejacket is light and comfortable to wear. It can not be made to automatically inflate so is only suitable for good swimmers, and worn in low risk situations.
It is particularly suited to rowing ashore to explore as it is extremely compact. It is awkward to inflate, as the bladder has to be removed from its pouch and passed over the head before
pulling the inflation tag.
Automatic Inflation
The advantages of automatic inflation are obvious… if someone who can’t swim falls overboard or if someone is knocked unconscious, then it could mean the difference between life
or death. There are two common types of inflator, each with its advantages.
Salt Crystal (or silicone) Inflation - This is the original type of automatic inflation. A cartridge filled with salt
crystals is positioned to retain a firing pin. When immersed in water, the salt dissolves allowing the firing pin to pierce a carbon dioxide cylinder, inflating
the lifejacket. It is a reliable, almost foolproof system which results in almost instant inflation. The main drawback with this system is that it has a tendency to inflate the
lifejacket accidentally. Water dripping down onto the jacket in the wet locker can easily dissolve the crystals.
Hydrostatic or “Hammer action” Inflation - This more
advanced system was designed to get around the accidental inflation tendency of the salt-crystal system. The head will not fire unless immersed adequately in water for the firing head to
come under pressure. Whilst virtually eliminating any chance of accidental inflation, many people feel that there is an increased chance of no inflation occurring, or a substantial
delay before inflation. We are not aware of any real evidence to support this view.
Harness
Most inflatable lifejackets are available with or without a harness. This is essentially just a D-ring stitched into the webbing, but it has to conform to certain
regulations. It is well worth paying the extra to have in integral harness, but it must be accompanied by a crotch strap.
Crotch or leg Strap
Not included with all lifejackets, it should be added if necessary. The absence of a crotch or leg strap will mean that the jacket can ride up and pull off over the head
especially if pulled by a harness lifeline.
Hoods
Rarely included as standard, a hood could well make the difference between life or death during prolonged exposure. A large percentage of one’s body heat is lost through
the head and the constant cooling effect of waves will make matters worse. Hoods have been proved to significantly increase the chances of survival. They are available as
after-market accessories.
Lights
Again, these are rarely fitted as standard. Lights which illuminate on contact with water are the most popular, but are not necessarily the most visible.
Strobes can be seen better, but the batteries will not last as long. Sealed batteries are the norm, but are expensive to replace, often requiring the whole light to be replaced. Also
they will be set off even in daylight, wasting the precious battery.
What Size should I choose?
The standard size for all adults is 150N. Children under nine years old normally have 100N jackets. 270N lifejackets are also available and are generally recommended
for commercial and prolonged situations.
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