Section 183.420 - Batteries(a) Each installed battery must not move more than one inch in any direction when a pulling force of 90 pounds or twice the battery weight, whichever is less, is applied through the center of gravity of the battery as follows:(1) Vertically for a duration of one minute.(2) Horizontally and parallel to the boat's center line for a duration of one minute fore and one minute aft.(3) Horizontally and perpendicular to the boat's center line for a duration of one minute to starboard and one minute to port.(b) Each battery must be installed so that metallic objects cannot come in contact with the ungrounded battery terminals.(c) Each metallic fuel line and fuel system component within 12 inches and above the horizontal plane of the battery top surface as installed must be shielded with dielectric material.(d) Each battery must not be directly above or below a fuel tank, fuel filter, or fitting in a fuel line.(e) A vent system or other means must be provided to permit the discharge from the boat of hydrogen gas released by the battery.(g) Each battery terminal connector must not depend on spring tension for its mechanical connection to the terminal.CGD 73-217, 42 FR 5944, Jan. 31, 1977, as amended by CGD 81-092, 48 FR 55736, Dec. 15, 1983