What type of documents is the ERG primarily considered to be?

The Emergency Response Guidebook (ERG) is primarily considered a reference guide for emergency responders. It is specifically designed to assist first responders at the scene of a hazardous materials incident. The ERG provides critical information on the identification and initial response to hazardous materials emergencies, including guidance on evacuation distances, protective measures, and basic emergency response procedures.

Its purpose is to facilitate swift and effective action during emergencies involving hazardous materials, ensuring that responders have the necessary information at their fingertips to make informed decisions. The ERG includes a color-coded section for quickly identifying hazardous materials by their UN number, along with various isolation and safety measures that should be taken. This emphasis on immediate and practical response makes it a vital tool for emergency services in managing hazardous situations.

In contrast, the other options focus on aspects that do not align with the ERG's primary purpose. Legal contracts and documentation templates serve different functions within hazardous materials management that are not related to immediate field response. Similarly, while the ERG may provide training elements, it is not a comprehensive training manual aimed at building safety practices.