What is the flash point range for highly flammable substances?

The flash point of a substance is the lowest temperature at which it can vaporize to form an ignitable mixture in air. Highly flammable substances typically have a flash point below 100°F. This means that such materials can ignite easily at relatively low temperatures, posing significant safety risks in environments where they are stored and handled.

Substances with a flash point under 100°F are classified as flammable liquids and need to be managed with care to prevent accidents, particularly in situations where they could be exposed to open flames or sparks. Knowing this identifying feature helps in assessing the hazards associated with handling and using these substances.

In contrast, the classification based on other ranges, such as less than 70°F or below 80°F, is more specific and would encompass a wider variety of highly flammable materials but does not capture the general threshold where the majority of flammable substances are categorized. The option referring to above 100°F does not apply to highly flammable substances, as these would generally be considered less hazardous compared to those with lower flash points.