60. When required to work in an area where explosive gases may accumulate, you should use hand tools which are __________.

Non-ferrous hand tools are required in areas with explosive gases to minimize the risk of sparks that could cause ignition. Ferrous tools, like high carbon steel, and tools with ferrous coverings, produce sparks; Coast Guard approval is irrelevant to the tool's material composition. Therefore, non-ferrous tools are the only safe option.