Scuba tanks should be a part of every diver's kit. While they contain no air, they do contain a large volume of free gas, which is generally greater than the amount of water they can hold. 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. Below is a list of the most common scuba tanks, along with their sizes.
scuba tanks contain no air
The standard aluminum 80 can holds 77 feet3 air. Trimix, a dive gas, is 10-20% smaller than air. A higher maximum operating pressure doesn’t necessarily mean that there is more air. Although manufacturers overestimate the tank's capacity, they often do so. It is therefore important to check the capacity of each individual cylinder against the actual volume.
They have a greater volume of free gas than their water capacity
Technical divers use different mixed gases than recreational divers, and their true air and Trimix capacities are less than their actual water capacities. Helium, for example, is less compressible than air, so the true air and Trimix capacities are smaller than their water capacity. The true air volume of Double HP117 cylinders is 235 ft3, while Heliair 10/50 cylinders have a true capacity of 216 Ft3. Use the Z Factors (SCUBA tables) to determine the correct mixed gasoline capacity.
They are made from aluminum or steel
When choosing between a steel and an aluminum scuba tank, consider which is more suitable for a divers' needs. Steel tanks can withstand deeper dives and are more durable. This durability comes at a price. Aluminum tanks are more susceptible to structural fractures and can prove dangerous. A steel tank can also be more expensive than an aluminium one. But aluminum tanks are now the industry standard.
They come in a variety of sizes
Two materials are used to make scuba tanks: aluminum and steel. Steel tanks are lighter and more durable, but tend to weigh more. An aluminum tank may be better if you plan to dive frequently and need to carry a weight belt. You should know that aluminum tanks can be heavier than steel tanks and are therefore lighter than steel tanks. Steel tanks can be used for local and drysuit diving.
They must be inspected often
There are many methods to test your scuba tanks. Hydrostatic testing usually is done below the tank's neck. You can also inspect the tank visually to detect corrosion and contamination. Tumbling is another method to inspect the tank's condition. Tumbling involves filling it with media and spinning it for a certain period of time to remove dirt and other contaminants. If the tank's sound is unusual, it might be an indication that it needs to get cleaned.