Abstract: Employee #1, the operator of a Grove RT 630 crane, had shut down the crane for refueling and lubricating by the company service truck. The delivery man placed a 7 to 8 oz can of Aviex starting fluid, a combination of ether and propane, on the floor of the crane under the seat. The crane cab has a diesel fuel heater that is on a separate system from the crane motor, meaning the heater can be left on while the motor is off. The crane operator was sitting in his cab during lunch hour with the motor off when the contents of the can expanded until the can ruptured and ignited into a brief flash fire that burned Employee #1. Tools, lubricating materials, and other supplies are normally kept in a toolbox at the front of the crane, not in the cab. The operator had no need for starting fluid at the time and if the delivery man had handed the fluid container to him he would have placed it in the toolbox. Employee #1 received on-the-job safety training and attended regularly scheduled onsite tool box safety meetings. He is required to wear a hard hat when he is outside the crane cab at a job site.