Which liquids require a permit if stored, handled, or used in amounts exceeding 5 gallons?

The requirement for a permit when storing, handling, or using liquids in amounts exceeding 5 gallons primarily pertains to Class I liquids, with certain specific exclusions. Class I liquids are defined as those with a flashpoint below 100°F, making them highly flammable and thus present a significant fire hazard. The regulation aims to ensure that appropriate safety measures and standards are in place for the storage and use of these dangerous substances, minimizing the risks to life and property.

In the context of fire safety, the control and oversight of these materials are critical in preventing incidents that could arise from their flammability. The permit process typically involves safety inspections and adherence to specific codes that dictate how these liquids should be stored, handled, and used, ensuring compliance with fire safety regulations.

Other liquid categories like Class II and combustible liquids do not impose the same stringent permit requirements for amounts over 5 gallons due to their higher flashpoints and reduced risk compared to Class I liquids. Flammable solids, while also hazardous, are regulated under different criteria and wouldn't directly relate to this specific question about liquid classifications.