How Does a Rebreather Work?
To understand how a rebreather works, let’s look at a normal scuba tank first. With a traditional scuba tank, every time you breathe in, you draw fresh oxygen or surface air from the tank. When you breathe out, the air (carbon dioxide) is exhaled into the water around you (this is what makes bubbles).
How Does a Rebreather Differ From a Traditional Scuba Tank?
Essentially, a rebreather takes advantage of the oxygen resource in your exhaled air and recirculates it back to your mouthpiece, so you can breathe it over and over again. The breathing loop that a rebreather creates extends your oxygen supply. Most divers who use rebreathers choose them because they are a more efficient use of oxygen and they are nearly silent (don’t disturb marine life). There are other benefits as well, such as you don’t exhale most of your body heat with a rebreather the way you do with a traditional tank, so you stay warmer. And deep water scuba divers have fewer decompression issues when they use rebreathers.But to rebreathe your air safely, the rebreather has to do a few things.http://www.scubadiving.com/training/basic-skills/are-you-ready-rebreathers
It has to scrub your exhaled air of carbon dioxide.
To do this, the rebreather circulates your exhaled air through a canister of sodium hydroxide. Sodium hydroxide turns carbon dioxide into a hard solid (called calcium carbonate). Once it is solid, the carbon dioxide can’t recirculate back to your mouthpiece.
Give you more oxygen.
There isn’t a lot of oxygen left in the air we exhale, so it needs to be supplemented with additional oxygen. Rebreathers have a small canister that adds oxygen or a gas combination to the breathing loop.
Employ the use of oxygen sensors.
It is important the rebreather can monitor the oxygen pressure in the breathing loop and use this information to control the amount of oxygen or mixed gases that is added to the breathing loop.
Who Uses Rebreathers?
Many divers are choosing to use rebreathers over traditional tanks because they are a better use of resources. Traditional tanks waste a lot of oxygen but you don’t get this waste with a rebreather. Rebreathers are also significantly lighter. This is because traditional tanks have to employ the use of nitrogen which takes up most of the space in the tank. Rebreathers don’t use nitrogen so the same amount of oxygen that you would get with a traditional tank would be lighter in a rebreather.
Divers who like to go deeper than the “no decompression” depths also like rebreathers because they can stay down longer without incurring an obligation to decompress. And if the divers do find that they have to decompress, it is usually a shorter decompression time than with traditional tanks.
Rebreathers are almost completely silent and they produce no bubbles or very few bubbles. This is important for observing marine life as the bubbles emitted from a traditional tank are “loud” and will alert marine life to the diver’s presence. Initially, rebreathers were designed for military use. Now they are frequently used by advanced scuba divers who have undergone specific training on how to use a rebreather.visit the original site for more information.