Scuba tanks are an essential part of every scuba diver’s kit. Although they are not air-filled, they do hold a large amount of gas. The tank size will vary depending on what type of diving you do. You'll need to select the right tank based upon the water type you intend to use. Here are the main types of Scuba Tanks and their sizes.
scuba tanks contain no air
The standard aluminum 80 cylinder can hold 77 feet3 of air. Trimix, a type dive gas, has a capacity of ten to twenty percent less than air. Similarly, a higher maximum service pressure doesn't necessarily mean more air. Although manufacturers often exaggerate their tanks' capacity. Therefore, it is important to compare each cylinder's capacity with the actual volume of air inside.
They are capable of storing more free gas that their water capacities.
Technical divers use mixed gases differently to recreational divers. Their true air and Trimix capacities, however, are lower than their actual water capacities. For example, Helium is more compressible than air so their true air and trimix capacities are lower than their water capacities. Heliair 10/50 is true to its air capacity at 216 ft3 while Double HP117 has an air volume equivalent to 235 ft3. You can use the Z Factors of SCUBA tables to determine the correct mixed gases capacity.
They can be made of aluminum or steel
If you are faced with the choice between an aluminum and a steel scuba tank, make sure to consider what is best for your needs. Steel tanks are more robust and can withstand deeper underwater dives. However, this durability comes with a price. Aluminum tanks can easily develop structural fractures which can lead to serious injury. A steel tank costs more that an aluminum one. Aluminum tanks are the industry standard.
They come in a variety of sizes
Scuba tanks are made from steel or aluminum. Steel tanks tend to be lighter and more durable than aluminum, but they are heavier. An aluminum tank may be better if you plan to dive frequently and need to carry a weight belt. But aluminum tanks are heavier than steel tanks. Before purchasing an aluminum tank, you need to be aware of your weight requirements. Steel tanks are great for drysuit diving and local scuba diving.
They must be inspected regularly
There are many ways to inspect your scuba tank. Hydrostatic testing is usually stamped into the metal beneath the neck of the tank. Visual inspections can be used to help detect corrosion or contamination. Tumbling can be used to test the condition of your tank. Tumbling involves filling your tank with media, and then spinning it for a period of time to remove any dirt or other contaminants. It may be necessary to clean the tank if it sounds rough.