On a boat what causes the greatest fire danger?

The greatest fire dangers on boats are:

• fumes of flammable or combustible fuels;
• fuel spills near hot engines, cooking or heating appliances;
• use of volatile chemicals for cleaning, stripping, or painting;
• unsafe disposal of smoking materials;
• improper disposal of tung oil rags and other drying chemicals;
• use of propane/butane or other torches or electric heat guns;
• use of fireworks, flare guns or firearms;
• engine backfire; and
• anything else where fuel, air and a source of ignition are mixed.