What type of hazard do flammable substances pose?

Flammable substances primarily pose a fire hazard. This type of hazard relates to the potential for fire or explosion when these substances come into contact with ignition sources such as flames, sparks, or high temperatures. In settings like esthetics practices, the use of certain products that contain alcohol or other volatile compounds increases the risk of fire if not stored or handled properly.

Understanding a fire hazard is crucial for maintaining safety standards in a workspace, particularly in environments where products may accumulate heat or where electrical equipment is in use. While flammable substances can also have health, environmental, and chemical implications, the immediate risk they pose during use or storage revolves around their ability to ignite and cause fire, making fire hazard the most relevant categorization in this context.