Hazardous Materials (HAZMAT) are found everywhere. They are prevalent in industrial facilities, and can be found in residential homes as well. Trucks, trains, and planes can transport these hazards through areas where they may not usually be found. HAZMAT materials can pose airborne, contact, ingestion, and radioactive threats so they are not always easily identified.
Industrial facilities have HAZMAT materials marked. Any material posing any type of risk (including non-HAZMAT) is listed in a Material Safety Data Sheet (MSDS) binder. Most homes do not have this level of identification and safety. Be sure you know where your hazardous materials are kept, and consider securing or marking them to avoid household incidents.
Image: HAZMAT Placards shown by hazard class.