We test a wide variety of cylinders, including:
- Scuba Tanks
- Paint Ball Cylinders
- CO2 Fire extinguishers
- SCBA – Fire safety and Hazardous Materials breathing bottles
We do work for private parties as well as many government agencies, municipalities, large companies, and industrial groups, including PepsiCo, local fire departments, ambulance services, Oregon State Fire Marshal Hazmat teams, County Sheriff Search and Rescue teams, fire extinguisher and restaurant hood manufacturing, installation, and service companies, and many more.
Hydrostatic Testing (Hydro Test):
For DOT regulated cylinders is required by Federal law. Very basically*, any high-pressure gas cylinder over two inches in diameter which is loaded into and transported by plane, train, or automobile needs to be Hydro-Tested. One way to tell if your cylinder needs to be tested is to look for the US Department of Transportation number. If the Bottle (Cylinder) is older it may have an “ICC’ number (DOT was formerly called the “Interstate Commerce Commission”). The number will look something like this: DOT3AL-3000 or ICC3AA-1800. This number denotes regulation by the Federal Transportation Division (DOT or ICC), the materials and standards it was manufactured under (3AL or 3AA), and the legal working pressure (1800 or 3000).
Water Jacket Hydrostatic Testing:
Your cylinder will be emptied, the valve removed, and the cylinder visually inspected. It will be filled with water and a special adapter will be threaded into the neck. Your cylinder will be lowered into a much larger tank that is also filled with water and then sealed up. The reason for this is that water does not compress and as pressure is applied to the water inside your cylinder it will expand and we can measure how much water it displaces. Most cylinders are pressurized to 3/5ths their rated pressure. That means that a 3000 PSI scuba tank will be tested at 5000 PSI. At this high pressure your gas cylinder will have a certain amount of permanent expansion. We record these pressures and volume changes. For most cylinders a maximum permanent to total volume ratio, set by the U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (USDOT – PHMSA), is 10% permanent expansion to total expansion ratio.
* This is not meant to be an expansive text, but a primer to teach you the basics of the hydro-testing process. There are many Federal regulations that govern the transportation, handling, filling, repair and hydro-testing of high pressure cylinders. These rules are found in publications like the Code of Federal Regulations (CFR) part 49, The Compressed Gas Association Inc. Guide (CGA), OSHA guidelines and other government texts.