Hercules Shipbuilding Company was a major participant in Baltimore's maritime sector, manufacturing ships for commercial usage as well as wartime Navy construction and maintenance. Many of the Hercules Shipyard employees were exposed to harmful dust and fibers while loading and unloading asbestos-containing materials, and during construction activities. Workers involved in repairing Navy vessels in shipyards were also exposed to asbestos on a continuous basis owing to the high concentrations of asbestos fibers in damaged and war-torn ships. Exposure levels at shipyards were increased due to a failure to equip employees with personal respiratory protection.