How Do you Read The Markings On A SCUBA Tank?

By Jose Cernuda

Understanding the Markings on Your SCUBA Tank

Have you ever wondered what all those markings on your SCUBA tank mean? Many people don't know it, but many of the markings that go on SCUBA cylinders are required by law. In the United States, the Department of Transportation regulates SCUBA cylinders. In Canada, it's Transport Canada that regulates SCUBA cylinders. Every country has their own regulatory authority so these two are just examples. 

On most SCUBA tanks the engravings on the shoulder will  indicate the following:

  • Manufacturer
  • The serial number of the cylinder
  • The material the cylinder is made out of (steel or aluminum)
  • Tank capacity (how many cubic feet or liters does the tank hold)
  • Service Pressure (what amount of pressure the tank can be filled to)
  • Original Hydrostatic date (this tells you the age of the cylinder)
  • Department of Transportation or other regulatory markings certifying that the cylinder has passed certain minimum requirements set by the government

Below is an example of markings you’d find engraved on a Luxfer aluminum 80 and next to it an explanation of what the markings mean.

Illustration of the engravings on a luxfer aluminum 80