Scuba Tank Size Chart
Samuel Johnson March 7th, 2022 Posted In: Articles Tags: SCUBA
Scuba Tank Size Chart
SCUBA cylinders or SCUBA tanks are used to hold compressed air or a mix of gasses that a diver can breathe while underwater. What does SCUBA stand for? Find out! There are many different sizes of SCUBA tanks available from small rescue tanks to large steel cylinders. However, there are only a few manufacturers of these tanks.
SCUBA Tank Sizes
The best known manufacturers of SCUBA tank cylinders are Catalina, Faber, Luxfer, Metal Impact, and the now closed Pressed Steel Tank Co (PST). Cylinder specifications are regulated by the Department of Transportation (DOT) in the U.S., and various regulatory entities internationally like Transport Canada (TC). Here are some SCUBA cylinders by various manufacturers and their related specifications:
SCUBA Cylinder Size Chart (In order by height or length)
| Manufacturer | Model #(HP = HighPressure) | Capacity (Volume in Cu Ft) | Length/Height (Inches) | Diameter (Inches) | Weight (When Empty in lbs) |
| Metal Impact | S06 | 6.0 | 11.1 | 3.20 | 2.5 |
| SpareAir | 300PK | 3.0 | 13.4 | 2.25 | 2.2 |
| Metal Impact | S40 | 40.0 | 14.6 | 5.25 | 15.3 |
| Catalina | S19 | 19.0 | 17.7 | 4.38 | 7.8 |
| Faber (Steel) | HP80 | 80.0 | 20.9 | 7.24 | 28.6 |
| Catalina | S80 | 77.5 | 25.9 | 7.25 | 31.3 |
| Luxfer | S106W (HP) | 105.0 | 26.1 | 7.40 | 33.8 |
| Metal Impact | S100 | 98.8 | 26.2 | 8.00 | 41.1 |
| Faber (Steel) | HP120 | 120.0 | 29.1 | 7.25 | 39.2 |
Differences between U.S. and international standards, when it comes to SCUBA tanks, boil down to imperial versus metric measurements. The Department of Transportation (DOT) in the U.S. uses Pounds per Square Inch (PSI) instead of Bars in reference to pressure. Inches (In) instead of millimeters(Mm), Cubic Feet (Cu Ft) versus liters (L), and so on. Most of the SCUBA cylinders you will see are rated up to 3000 PSI. There are times when a tank can be overfilled, but this is complicated and depends on many conditions.
SCUBA Tank Safety
Safety is the priority when dealing with compressed gasses. Also check out these SCUBA Diving Safety Rules. There are High Pressure (HP) tanks, like the Luxfer S106W rated for 4350 PSI, and Low Pressure (LP) tanks as well. Air fill stations like those found at Dive shops are typically geared towards 3000 PSI tanks and the compressor may not be able to fill High Pressure (HP) or non standard tanks to capacity.
1 Bar or 14.5 PSI, is roughly equal to the average atmospheric pressure of the Earth at sea level.
Which SCUBA cylinder is right for you depends a great deal on personal preference as well as the location, depth, and length of your dive. Looking at the table above you can see the larger tanks become quite heavy when empty and even heavier when filled with compressed air! An AL80 SCUBA cylinder, which is an aluminum 80 cubic foot tank, can increase in weight by over six pounds when filled. Notice that a steel 80 cubic foot capacity tank like the Faber HP80 weighs less empty than a comparable aluminum version and is almost five inches smaller!
SCUBA Tank Size Chart Continued
Total weight can become an issue when you factor in other SCUBA gear. Check out this blog “How Heavy is a SCUBA Tank & Gear?” for more info. Steel cylinders are stronger and manufacturers can use less material to make them when compared to an aluminum tank of the same capacity. Disadvantages of steel tanks include corrosion potential and increased cost. One of the most commonly used rental and training cylinders at SCUBA dive shops are the aluminum (AL) 80 cubic foot tanks.
The length of these tanks range in the area of 21-26 inches and are generally well handled by beginners and novices. A beginner SCUBA course will cover much of the basics and science behind compressed air cylinders and how to safely operate them. You may also be interested in this blog on the reasons to wear a wetsuit. One will often see SCUBA cylinders referred to by their capacity rather than their length or actual size.
In fact, SCUBA tanks come stamped at the top with regulatory information that includes the metal type, manufacturer, original hydrostatic test date, and capacity at service pressure. Divers can customize their SCUBA loadout with multiple tanks, different yokes and adaptors, and even take along an emergency SpareAir container.
SCUBA Tank Sizes
There are a wide variety of SCUBA tanks in different sizes, metals, and capacities. One could stop by a local SCUBA shop to examine some available options and compare the size and weight. Generally the higher the capacity, the larger and heavier the cylinder. SCUBA tanks do have a limited lifetime depending on maintenance and general care. They must undergo hydrostatic testing and visual inspections often to prevent accidents and underwater emergencies. The chart shown earlier helps compare some of the major differences between SCUBA tanks available on the market today.
