Gasoline with a flash point of -45°F and a Reid vapor pressure of 6.9 PSI would be classified as:

Gasoline is classified based on its flash point and Reid vapor pressure, which are critical factors in determining its flammability and associated hazards. A flash point of -45°F indicates that the gasoline is highly volatile and can produce flammable vapors at very low temperatures. This low flash point classifies it as having a high risk of ignition, which is an important consideration for safety.

The Reid vapor pressure of 6.9 PSI further indicates the volatility of the gasoline. A Reid vapor pressure between 6.0 to 8.0 PSI typically aligns with Grade C classifications. This is a crucial threshold, as it suggests that the gasoline can produce significant amounts of vapor at standard atmospheric conditions, enhancing its flammability potential.

Therefore, both the flash point and Reid vapor pressure provide critical information that securely place this gasoline within the Grade C category. Other grades have different criteria based on flash point and vapor pressure that would not apply here. Understanding these classifications is vital for safe handling, storage, and transportation of fuel products like gasoline.