33 CFR § 183.588 - Slosh test.
A fuel tank is tested by performing the following procedures in the following order:
(a) Perform the static pressure test under § 183.580.
(b) Perform the pressure impulse test under § 183.586.
(c) Secure the tank to the platform of a tank rocker assembly.
(d) Fill the tank to one-half capacity with water.
(e) Cap and seal each opening in the tank.
(f) Apply 500,000 cycles or rocking motion 15 degrees to each side of the tank centerline at the rate of 15 to 20 cycles a minute. The axis of rotation of the rocker and fuel tank must be perpendicular to the centerline of the tank length at a level six inches or less above or below the tank's bottom.
(g) Perform the static pressure test under § 183.580.