Final answer:
During installation, case crossings should be inspected to ensure the carrier pipe is supported, sealed, and protected from the casing to maintain the safety and integrity of the pipeline system.
Step-by-step explanation:
Case crossings should be inspected during installation to ensure that the carrier pipe is supported, sealed, and protected from the casing. This is a crucial part of pipeline infrastructure, where the integrity and safety of the pipeline system are maintained by properly installing the carrier pipe within a casing pipe. The carrier pipe must be supported to prevent sagging or buckling, sealed to prevent the ingress of contaminants, and protected to avoid any damage from the casing or external environments.