GALVESTON — A Channelview man working at a Galveston shipyard died Monday afternoon in a construction-related accident involving heavy machinery, an official said. James Mays, 40, was operating a backhoe from outside the cab shortly after 2 p.m. when he became pinned by the boom, said John Florence of the Galveston County Medical Examiner’s Office. Mays was a contract employee working at Southwest Shipyard, 1002 Texas Clipper Road, on Pelican Island, Florence said. A crew was digging a hole on a project at the time of the accident, Florence said. “For some reason, he got off the backhoe and was standing behind it when he went to move the boom,” Florence said. The pedal controlling the boom is capable of being maneuvered even when the operator is outside the cab, Florence said. “It swung around and penned him between the back support leg and the boom,” Florence said. “Another worker pushed the other pedal and freed him.” Mays was pronounced dead at the scene, Florence said.