This document specifies the requirements for the ultrasonic testing of spheroidal graphite cast iron castings and the techniques for determining internal discontinuities by the pulse-echo technique. This document does not apply to ultrasonic testing of the nodularity of spheroidal graphite cast irons. This document does not apply to phased array technique and to transmission technique. NOTE The transmission technique has insufficient sensitivity to detect the discontinuities found in spheroidal graphite cast iron castings and is used in exceptional cases only.