What sound indicates a delamination when using a tap hammer?

When assessing the condition of an intermodal dry cargo container using a tap hammer, a dull, hollow sound is indicative of delamination. This sound arises from the separation of the layers of material, which creates a void space within the structure. A healthy, intact surface will produce a solid and sharp sound, as the layers are bonded effectively together. Thus, when delamination occurs, the sound becomes dull and hollow, signaling that the integrity of the container's construction has been compromised.

The other types of sounds mentioned, such as a high-pitched sound, metallic clang, or whistling, do not provide the same diagnostic information regarding potential delamination. High-pitched sounds may indicate a solid surface but do not specifically highlight issues of layer separation. A metallic clang generally suggests interaction between hard surfaces or materials and does not relate to the condition of layers. A whistling sound, while it may indicate air movement through a gap, does not serve as an effective diagnostic indicator of delamination within the container's structure. Understanding these distinctions is crucial for properly assessing container integrity during inspections.