Hazardous substances, known as HAZMAT in international terms, refer to substances that can cause harm to property, the environment, or organisms if mishandled or released due to their chemical composition. When it comes to transporting hazardous goods, distinct procedures are followed compared to other shipments. The primary objective is to ensure the secure transportation of these goods. By adhering to specific standards in the air transportation of dangerous substances, risks to human life, the environment, and flight safety are minimized, thereby ensuring a safe and sound transportation process.

Hazardous substances are defined by the UN Committee of Experts in nine classes:

- Explosives

- Gases

- Flammable Liquids

- Combustible solids

- Oxidising agents and organic peroxides

- Toxic and infectious substances

- Radioactive substances

- Abrasives

- Various hazardous substances