What information is indicated by the UN number on hazardous materials?

The UN number serves as a unique identifier for hazardous materials and is essential for their safe and effective transport. This number is part of the United Nations' system for classifying hazardous substances, which facilitates recognition and regulation during transportation. Each UN number corresponds to a specific hazardous material, ensuring that emergency responders, carriers, and shippers can identify the substance quickly and accurately, thus enabling the appropriate safety and handling measures.

For instance, when a vehicle carrying a hazardous material is involved in an accident, the presence of the UN number allows emergency services to determine the specific risks associated with that material. This system enhances safety in logistics and emergency response, supporting the broader goals of hazardous materials transportation regulations.

The other options do not accurately describe the purpose of the UN number. It does not convey pricing, volume, or supplier information, as its primary function is to classify and identify hazardous materials.