Posted by
liren on Thursday, June 11, 2009 4:04:00 PM
A diving suit is a garment or device designed to protect a diver from the underwater environment. Modern diving suits can be divided into two kinds:
* "soft" or ambient pressure
diving suits - examples are wetsuits,
dry suits, semi-dry suits and dive skins
* "hard" or atmospheric pressure
diving suits - an armored suit that permits a diver to remain at atmospheric pressure whilst operating at depth where the water pressure is high.
Wetsuits are relatively inexpensive, simple,
Neoprene suits that are typically used where the water temperature is between 10 and 25 °C (50 to 80 °F). The foamed neoprene of the suit thermally insulates the wearer. Although water can enter the suit, a tight fitting suit prevents excessive heat loss because little of the water warmed inside the suit escapes from the suit.
Proper fit is critical for warmth. A suit that is too loose will allow too much water to circulate over the diver's skin, robbing body heat. A suit that is too tight is very uncomfortable and can impair circulation at the neck, a very dangerous condition which can cause blackouts. For this reason, many divers choose to have wetsuits custom-tailored instead of buying them "off-the-rack." Many companies offer this service and the cost is often comparable to an off-the-rack suit.
Diving wetsuits are limited in their ability to provide warmth by two factors: the wearer is still exposed to some amount of water, and the insulating Neoprene can only be made to a certain thickness before it becomes impractical to don and wear. The thickest commercially-available
wetsuits are usually 8mm thick. Other common thicknesses are 7mm, 5mm, 3mm, and 1mm. A 1mm suit provides very little warmth and is usually considered a dive skin, rather than a wetsuit.
Reprinted from:
Wiki