Fog warning devices are tools designed to alert individuals about low visibility conditions caused by fog. These devices can be found in various forms, including buoys in waterways, roadside signs on highways, and weather stations that monitor atmospheric conditions. They help ensure safety for drivers, sailors, and outdoor enthusiasts by providing timely warnings. Typically, fog warning devices use sensors to detect fog density and visibility levels. When conditions become hazardous, they activate alarms or display warning messages. This information is crucial for preventing accidents and ensuring that people can take necessary precautions when traveling in foggy environments.