A method of leak testing a fluid passage of a part manufactured from a low conductivity material includes measuring an electrical resistance between an interior wall surface of the fluid passage of the part, and an exterior wall surface of the fluid passage of the part. The measured electrical resistance is compared to a threshold value to determine if the measured electrical resistance is equal to or greater than the threshold value, or if the measured electrical resistance is less than the threshold value. The threshold value is equal to a nominal wall thickness of the fluid passage multiplied by a resistivity of the material used to form the part. The part passes the leak test when the measured electrical resistance is equal to or greater than the threshold value. The part fails the leak test when the measured electrical resistance is less than the threshold value.