What do ISO markings on a container signify?

ISO markings on a container signify compliance with ISO standards, specifically the International Organization for Standardization (ISO) regulations pertaining to the design and performance of shipping containers. These standards ensure that containers are built to specific criteria, which facilitate safe and efficient transport and interchangeability across various modes of transport. The presence of ISO markings indicates that the container meets established safety and quality benchmarks, which is crucial for standardization in global trade.

The other options do not accurately represent the role of ISO markings. While containers may indeed be used to transport hazardous materials, this association is not what the ISO markings denote. Ownership is typically indicated by other markings, such as a company logo or owner identification number, and containers do not have an expiration date in the same sense that perishable goods might. Instead, their usability is often subject to periodic inspections and assessments based on the ISO guidelines.