In a hazmat incident involving a truck carrying magnesium scrap, where should you initially look for guidance if the 4-digit number cannot be obtained?

When addressing a hazmat incident involving materials like magnesium scrap, looking for guidance on how to handle the situation is crucial for safety. In this scenario, if the 4-digit number—typically found on the material’s placard—is unavailable, the correct choice is to refer to the blue-bordered material index. This index includes information for hazardous materials that may not be listed using a four-digit number, providing critical information regarding their handling and emergency procedures.

Using the blue-bordered section is vital because it’s specifically designed to provide guidance on hazardous materials that require particular attention due to their unique dangers and properties. This includes information on health hazards, protective measures, and any specific response actions.

The other options may refer to different sections of material indexes, but they do not focus on the critical information regarding handling hazardous materials when specific identifiers are missing. By starting with the blue-bordered material index, responders ensure they are accessing the most relevant and specific guidance for the material they are dealing with, particularly in situations where standard identification methods are not possible.