What information must be included about the container's retest on a DOT label?

The inclusion of the retest date on a Department of Transportation (DOT) label is essential for ensuring the safety and reliability of pressurized gas containers. This date indicates when the container has been inspected and tested to confirm that it meets safety standards for continued use.

Knowing the retest date allows users to be aware of when a cylinder may need to be replaced or re-tested. It serves as a critical piece of information for maintaining safety in handling, storage, and transportation of gases. This regulation is important for preventing accidents that could arise from using outdated or improperly tested containers.

Other information, such as the type of gas stored, could be beneficial but does not specifically address the operational safety of the container itself over time. While the owner's contact information and usage instructions are helpful, they do not provide the necessary safety assurance that the retest date does. Thus, the retest date is the key piece of information that ensures compliance with safety regulations and guidelines established by the DOT.