1. All components in the fuel system must be capable of withstanding a 2.5 minute burn test (exposure to burning diesel fuel). You are not an engineer and so you may not know if any component is capable of withstanding this test. However, if it's suspect, such as an outboard primer bulb that is one-fourth the thickness of type A fuel hose, then it's worth noting and further research. In order to pass this test, Racor and other filters equipped with clear sight bowls must be equipped with heat shields. Most automotive versions of these filters, which lack the heat shield, do not meet this requirement.
  2. Drain valves on filters and tanks shall be of the variety that cannot be opened inadvertently (uncapped ball or lever type valves for instance). No other drains are permitted in the fuel system.
  3. If a sight glass is used for fuel level measurement, it must be equipped with valves at the top and bottom and it must carry a label indicating that valves are to be left in the closed condition at all times other than when measurements are being taken.
  4. All flexible (rubber) fuel lines must be USCG TYPE A. The hose should be marked with this information as well as date of manufacture every 12 inches.
  5. Any material touching a metallic fuel tank (mild steel or aluminum, stainless steel is prohibited except under very rare circumstances), chocks, hangers, supports, straps etc. must be non-hydroscopic in nature. This means, the tank may not be in contact with wood, carpeting or insulation. The tank must not rest on a shelf where water may stand. The tank bottom should be separated from the shelf surface by a one-quarter inch air gap.
  6. Tank tops must be self-draining and the tank bottom must be above the normal accumulation of bilge water.
  7. Fuel tanks must carry a label that is visible when the tank is installed indication the manufacturer, type of fuel for which it is rated, capacity, material and thickness, date, test pressure.
  8. Every fuel tank must be equipped with an accessible (accessible means it can be reached, even if a substantial amount of equipment has to be removed, as long as this does not require cutting holes in hull or decks) inspection port that will gain access into every baffled chamber of a tank.
  9. When the boat is in the static floating position, no fuel must enter the boat if an overflow should occur at the fill port.
  10. Fuel vent fittings shall be installed so they do not allow water to enter the system (even in rough weather). Fuel should not leak from this fitting while the tank is being filled.
  11. A shut-off valve is required at the fuel tank where fuel may siphon or in gravity feed systems. My opinion is that every fitting on every tank other than fills, should be equipped with a shut off valve located at the tank, for service and leak mitigation purposes.
  12. All metallic components that are in contact with fuel and the fuel tank must be grounded to the boat's bonding system. This means filters, valves, manifolds etc.
  13. Copper alloy components, such as brass, bronze and copper, must not make direct contact with aluminum tanks under any circumstances. A stainless steel insulating fitting may be installed between the aluminum and copper alloy.