This case study involves a hatch cover located on a pressurized barge unloading concrete. The hatch cover exploded as a workman was kicking off one of the locking cams holding the cover to the deck. The cover, attached to the barge by a hinge, utilized six locking cams to hold the pressure seal to the compartment. The cover was 0.51 metres in diameter and fabricated from A356-T6 aluminum. The pressure to off-load the cement was 206.8 kPa. A finite element study was performed to determine the stresses in the cover as a function of locking geometry. Fracture toughness tests to determine K_Ic, a nondestructive inspection to determine crack size and crack population, and a design study to determine pressure vessel design characteristics were undertaken. A failure analysis was also conducted. Results of the studies indicate that the design choices (internal piping, hatch cover attachment, and material selection) allowed a potentially catastrophic situation to develop. Recommendations for design improvements are given.