Which of the following correctly defines a flammable liquid?

A flammable liquid is defined as a liquid that has a flash point below 100°F. This definition is significant within the context of fire safety, hazardous materials handling, and regulatory standards, such as those established by the Occupational Safety and Health Administration (OSHA) and the National Fire Protection Association (NFPA).

The flash point is the lowest temperature at which a liquid can form an ignitable mixture in air. Liquids with flash points below 100°F are particularly dangerous because they can produce enough vapors at relatively low temperatures to ignite and possibly cause fires or explosions. Understanding this classification is crucial for anyone involved in fire investigations, safety planning, or dealing with hazardous materials.

In contrast, a flash point at or above 100°F identifies liquids that are considered combustible but not defined as flammable, making them less hazardous than flammable liquids. Similarly, options that narrow down the flash point range, such as between 70°F and 100°F or below 50°F, do not encompass the broader and more critical definition. Thus, the proper understanding centers around the threshold of 100°F, marking the distinction between flammable and combustible liquids.