A ton captain is a certified boat captain who is authorized to handle larger commercial boats that carry passengers, such as water taxis, ferries, tour boats, and boats used for commercial or recreational diving excursions. As a ton captain, you also handle any boats that that do not undergo inspection. Your duties and responsibilities include ensuring that the boat you captain is seaworthy and meets all safety standards. You also organize and oversee the crew of the boat. If you captain a passenger boat, you may have some responsibilities related to interacting with your passengers, but you can often delegate this task to a lower crewmember.