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A full-scale burn test of a 1992 compact pick-up truck was conducted to evaluate how temperature distributions changed over time, the manner in which the fire spread, and how burn patterns produced during the fire correlated with important characteristics of the fire such as the area of origin. After the fire was initiated on the lower portion of the dashboard of the test vehicle, it spread locally to nearby dashboard material and, at the same time, developed a strong temperature gradient from the ceiling to the floor. Once the ceiling temperature reached about 600°C, the rate of fire spread increased and, within 1 minute, the passenger compartment was fully involved. Initiation of the engine compartment fire, which occurred about 4 minutes after the passenger compartment was fully involved, was consistent with fire spread through the heating, ventilation, and air conditioning (HVAC) duct that passed through the passenger's side of the bulkhead.

Data from a full-scale vehicle burn test involving a cargo van illustrated how temperature distributions changed over time, the manner in which fire spread, and how patterns produced correlated to the origin of the fire. The fire was initiated on the driver’s side of the engine compartment and initially grew slowly with the high-temperature zone near the area of origin. Once the peak temperature reached about 540°C, the rate of flame spread increased such that over the next 4 minutes the fire spread across the entire engine compartment. In the next stage of the fire, which occurred shortly after full involvement of the engine compartment, the fire spread into the passenger compartment. A strong vertical temperature gradient developed from the ceiling to the floor and as the passenger compartment became fully involved, the passenger compartment temperatures both increased and became more uniform.

Temperature measurements during a full-scale burn test of a 2001 full-size pickup truck showed that the fire progressed in distinct stages in both the engine and passenger compartments. Although the fire started in the engine compartment and had a relatively long growth period, when a localized area reached about 700°C, a distinct transition occurred where the rate of fire spread increased, leading to full involvement of all engine compartment combustibles. As the engine compartment became fully involved, a hot gas layer then accumulated at the ceiling of the passenger compartment, producing a strong vertical temperature gradient. When the temperature at the ceiling reached about 600°C, another distinct transition occurred where the rate of fire spread increased, leading to full involvement of the passenger compartment. The highest temperature during the test occurred within the engine compartment in an area that had the greatest fuel load, and not the area of origin.