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. Listed below are the main types of scuba tanks and their sizes.
scuba tanks contain no air
The standard aluminum 80 cylinder has a capacity of 77 ft3 of air. Trimix, a type of dive gas, has a ten to twenty-percent lower capacity than air. The same goes for air. A higher maximum pressure doesn't necessarily indicate more air. However, manufacturers tend to exaggerate the tanks' capacities. You should therefore compare the capacity of each cylindrical against the actual volume.
They contain a volume of free gas greater than their water capacity
Technical divers use different mixture gases than recreational divers. The true air and trimix capacities of technical divers are smaller than their actual water capacity. Helium, for example, is less compressible than air, so the true air and Trimix capacities are smaller than their water capacity. Double HP117 cylinders contain a true air volume of 235 ft3 while Heliair 10/50 has a true air capacity of 216 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
It is important to decide which scuba tank is better for divers. Steel tanks are more durable and can withstand deeper dives. This durability comes with a price. Aluminum tanks can easily develop structural fractures which can lead to serious injury. Additionally, an aluminum tank will cost more than a steel one. But, aluminum tanks are now the industry standard.
They are available in various sizes
Scuba tanks can be made from two materials: aluminum or steel. Steel tanks are lighter, more durable and heavier than aluminum tanks. However, they tend to be heavier. A lightweight aluminum tank might be the best option if you intend to dive a lot or bring 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 excellent for drysuit diving as well as local scuba divers.
They should be inspected frequently
There are many options for checking your scuba diving tank. Hydrostatic testing is often done beneath the neck of a tank. A visual inspection is also a good way to find any corrosion or contamination. Tumbling can be used to test the condition of your tank. Tumbling involves filling it with media and spinning it for a certain period of time to remove dirt and other contaminants. If the tank sounds rattly, it may mean it needs to be cleaned.