Technical Visual Inspections Enhance Cylinder Safety

Author's note: Although this article is based upon Canadian and US laws and standards, the general content may provide useful information about cylinder safety.  Edited 2016.

Visual cylinder inspection (VCI) does not mean the same thing to all who claim to conduct VCI nor to those who write laws or guidelines about VCI. For example, the U.S. Occupational Safety and Health Administration (OSHA) requires all respiratory equipment including SCUBA and SCBA (S/S) used by employees to be visually inspected at least every month and after each use.
Also, OSHA requires that all pressurized cylinders employees may be exposed to shall be safe as determined by visual inspection.  The U.S. Department of Transportation (DOT) requires hydrostatic retesters to conduct a visual inspection as part of the retest process.  The Compressed Gas Association (CGA) publishes cylinder related safety guidelines that are, in some cases, incorporated into law by reference.  Even one cylinder manufacturer (Luxfer Gas Cylinders) and the scuba instructor associations NAUI, PADI, NASDS and SSI have, at one time or another, prepared information about VCI.  Although each of those associations stress the importance of a VCI, none tell the technician clearly just what it is or how to accomplish it.

The PSI-PCI, Inc. Visual Cylinder Inspector textbook, INSPECTING CYLINDERS is the best single volume source for technical VCI information about steel and aluminum S/S and composite SCBA cylinders. It was first published in 1987 and is now in its greatly expanded fifth edition.  PSI-PCI, Inc. produces a program for training employees to their level of exposure as required by the regulations called Cylinder Hazmat/Fill Station Operations Compliance Kit which is available for training by all current PSI-PCI trained visual inspectors.

Luxfer Gas Cylinders published an excellent guide in 1996 that clearly describes how to conduct a technical VCI on Luxfer aluminum scuba cylinders. Much of that information and procedures came from the program developed by PSI-PCI, Inc. over the past 17 years.  Luxfer also published a guide for inspecting SCBA cylinders.  The technical SCBA inspecting guide is printed in two volumes.  Volume I deals with Luxfer aluminum and composite cylinders made before 1988 and volume II covers newer solid wall and several composite materials.

The INSPECTING CYLINDERS book contains the details necessary for a thorough visual inspection.  However, it is not a substitute for formal training as required by USDOT.  A technical visual cylinder inspection is a complete assessment inside and out against standards and damage limits.  Cylinders that meet those standards are returned to service. Many cylinders that do not meet the standards can be serviced, usually cleaned or hydro retested, and returned to service. Damage or other conditions that fail to meet the allowable limits cause the cylinder to be condemned.  Condemned S/S cylinders should not be reconditioned.

For more information about PSI-PCI and cylinder inspection training and safety, visit our web site at, e-mail at  This e-mail address is being protected from spambots. You need JavaScript enabled to view it. or call us at 425.398.4300.  We train fire fighters, fill station operators, equipment repair technicians, hydrostatic retesters, scuba instructors, dive store staff and many more.