While operating a trash compactor on a client's property the injured worker noticed hydraulic fluid on the ground. He had punched the start button on the compactor and it began its cycle. While the compactor was cycling, he looked for the source of the hydraulic leak and in doing so reached forward to touch the hose. The hose became pressurized when the hydraulic ram reversed. There was a hole in the line and hydraulic fluid injected into his right thumb. He was hospitalized for chemical exposure and debridement of the thumb.