Hazmat Employee is an employee of the Springfield Nuclear Power Plant seen moving uranium.
He is seen transporting uranium and other assorted nuclear products. He is in a sealed room as it is a dangerous procedure. Homer - with Lenny, Carl and Charlie - plays a prank on him, pinching him on the behind with a robotic arm. He then drops the glowing green bar in his hand, releasing a lethal mist. He runs to the safety glass and bangs on it, pleading for help, but Homer and the others fail to respond. They do nothing, assured the glass will protect them. The safety glass seeps out the gas and they attempt to escape through an exit. However, the exit is only painted on and they're consumed by the mist. It is most likely the Hazmat Employee died from the mist as he seen dropping to the ground. Yet Homer and his friends all escape from the mist alive, which leaves a possibility that he also did. However, Charlie describes it as a "miraculous escape," implying there was more to the escape. This means the Hazmat Employee most probably survived.