Class I and II liquids or Class III liquids in containers exceeding 5.3 gallons at a specific temperature must not be dispensed by which method?

The correct response focuses on the method of dispensing Class I, II, and III liquids in containers exceeding 5.3 gallons. Gravity dispensing is not permitted for these types of liquids, especially at specific temperatures, due to safety concerns.

When liquids of these classifications are dispensed by gravity, there is an increased risk of spills, overflow, and uncontrolled flow into the surrounding area. This can lead to hazardous situations, such as fire or environmental contamination, particularly since Class I and II liquids are flammable. Additionally, governmental regulations and safety standards emphasize the importance of using methods that minimize risk during the handling of potentially dangerous substances.

Other methods, such as pumping, siphoning, or using a transfer hose, may have safety protocols or built-in protections that help reduce the risk of accidents. For instance, pumps can be equipped with automatic shut-offs or can be designed to prevent backflow, whereas siphoning is generally used with smaller amounts and requires careful handling to control the liquid flow. Thus, gravity methods are considered less safe for larger quantities of hazardous liquids.