ERG yellow pages provide __.

The yellow pages of the Emergency Response Guidebook (ERG) are specifically organized to provide the UN/NA ID numbers of hazardous materials. These numbers serve as a standardized identification system, allowing first responders to quickly locate important information about specific substances during emergency situations. When encountering a hazardous material incident, responders can use the UN/NA ID number to find guidance about the material's properties, associated risks, and recommended actions to take. This is crucial for ensuring safety and effective response measures in the face of chemical hazards.

The other options do not reflect the primary function of the yellow pages in the ERG, which is dedicated to these identification numbers rather than general instructions, material names, or safety recommendations. Those aspects are covered in other sections of the ERG.