Hazmat is short for “hazardous materials,” which means substances that could harm people, animals, or the environment if not handled carefully. These materials might be poisonous, flammable, explosive, radioactive, or corrosive (able to burn through things). Common examples include certain chemicals, gasoline, batteries, cleaning products, and medical waste.

You've probably seen hazmat warnings on trucks carrying chemicals along the highway, or noticed diamond-shaped hazmat labels on containers that indicate what kind of danger they pose. Workers who handle hazmat materials wear special protective suits to keep the dangerous substances away from their skin and lungs.

The word appears often in news reports about accidents or spills. When a hazmat team responds to an emergency, they're specially trained experts who know how to clean up dangerous spills safely and protect everyone nearby. Schools, hospitals, and factories all follow strict hazmat rules about storing and disposing of dangerous materials.

Even everyday items can be hazmat. Old paint, certain batteries, and some electronics contain materials that shouldn't just go in regular trash. That's why communities have special hazmat collection days where people can safely dispose of these items.