In column 1, the "+" sign means ____.

The "+" sign in column 1 of the Hazardous Materials Table indicates that the proper shipping name provided is applicable for the material regardless of its specific class. This means that even if a hazardous material can fall under various classifications, the name listed in column 1 is the one that should be used for shipping purposes across all potential classifications. This ensures standardization and clarity in the transportation of hazardous materials, allowing carriers and emergency responders to quickly understand how to handle the material safely.

Other choices refer to specific characteristics of materials, such as flammability, toxicity, and corrosiveness, but they do not pertain to the broader application of shipping names as indicated by the "+" sign in column 1.