What must be done to ensure proper packaging of HAZMAT for transport?

To ensure proper packaging of hazardous materials (HAZMAT) for transport, the packaging must be tested and certified to meet Department of Transportation (DOT) specifications. This is crucial because it guarantees that the packaging can safely contain the hazardous materials during transit, preventing leaks or spills that could pose risks to public safety and the environment. The testing process evaluates the packaging for its durability, strength, and resistance to possible chemical reactions with the substance it is meant to contain. Compliance with DOT regulations ensures that all safety standards are met, which is essential for the safe transportation of HAZMAT.

The other options do not address the fundamental requirements for safe HAZMAT packaging. Painting packaging a specific color does not contribute to its safety or performance in transporting hazardous materials. While having a tracking number may be important for logistics purposes, it does not impact the safety of the packaging itself. The requirement to ship within 24 hours is not a general rule for all hazardous materials and does not pertain to the packaging's integrity or compliance with safety standards.