P worked for D as a farm truck and machinery mechanic. P was removing a leaky fuel tank from a 1978 Ford F-250 pickup truck. He used a 4-ton floor jack to raise the truck and a floor creeper to roll under the vehicle on his back. Simmons hung a shop light with an incandescent bulb from the pickup's frame for illumination. The tank was less than half full of gasoline when P began working, and he did not drain that gasoline from the tank. P noticed the fuel tank was not secured with factory or replacement fastenings. P started using a pneumatic air-powered wrench to loosen a bolt securing the makeshift plumbing strap when the tank fell to one side, covering P in gasoline. He tried to escape from under the truck, but his foot caught on the shop light, which fell from the pickup's frame. The incandescent bulb shattered, and the gasoline ignited. His lawsuit was not barred by the Kansas Workers Compensation Act. D raised assumption of risk as an affirmative defense. Even though P claimed D was negligent P had the knowledge and experience to appreciate the fire risk and was voluntarily removing the fuel tank despite his awareness of that risk. The court granted D summary judgment. P appealed, arguing the assumption of risk doctrine should be overruled or, in the alternative, that disputed material facts prohibited summary judgment. The court of appeals affirmed. P appealed.