Cylinders that carry pressurized air are classified as hazardous by the Department of Transportation and shipping regulations for air cylinders are listed in the Code of Federal Regulations, Title 49, Parts 171, 172, 173, 178, 179 and 180. All carriers are subject to DOT regulations even though it is sometimes difficult to make a physical inspection of the air cylinders. In some cases the carrier can only examine the shipping documents, so he must do so carefully.
Carriers have reporting responsibilities for the air cylinders they carry; the cylinders must comply with Department of Transportation regulations. Reporting criteria is published in CFR, Title 49, Sections 171.15 and 171.16. The carrier can spot-check cylinders he is carrying by making sure the cylinders are not being reused if they are single-use cylinders, that they are not being used beyond their test date, that they have valve protection, that the valves are not defective and that there are no bulges, dents or corrosion. Also, the cylinders must have been refilled by the owner or with the owner’s permission and they must not have duplicated serial numbers or any other improper markings.
Air cylinders must be marked with inspection dates. Reusable cylinders must also be marked with the dates they were reinspected or retested. Retesting and reinspecting is required to take place at periodic intervals. Cylinders must also be marked properly with the hazard class, description, shipping name and technical name for the material being shipped. The contents must be correctly identified. Emergency response information and telephone numbers should also be on the cylinder. Empty cylinders must be marked “M7.” The markings must be legible and the symbols must be registered with the DOT.
Valve protection caps on air cylinders that call for them must always be in place while transporting, and they should be hand-tightened. Cylinders must be held in place vertically while being transported, but slings or magnets must not be used. Carriers move the cylinders by tilting and rolling them on their bottom edge. Carriers must not use the valve protection cap to lift the cylinder. A pressurized air cylinder must not be dropped, struck, or permitted to strike another cylinder. A cylinder that is frozen to a surface must not be pried with a bar; warm water should be used to loosen it. While cylinders are being stored they must be kept away from heat. They must also be stored in dry, well-ventilated locations.