As a marine plumber, you perform plumbing and pipefitting tasks onboard a ship. This includes installing new systems, repairing existing systems and tanks, and modifying pipes when making changes to a system. You perform electrical work when install pumps or similar equipment, inspect all piping to ensure it meets safety standards, and reroute tubing away from walkways and visible areas. Other responsibilities include working in potentially inclement weather, traveling to reach ships that need repair, and maintaining a friendly and professional attitude while dealing with customers.