What must be used with all round pin shackles to ensure safety?

To ensure safety when using round pin shackles, cotter pins must be used to prevent the pin from inadvertently coming loose during lifting operations. Cotter pins serve as a securing mechanism that holds the pin in place and stops it from sliding out, which can prevent the shackle from disconnecting under load. This is particularly important in rigging scenarios where safety is paramount, as a disconnected shackle can lead to dangerous situations, including potential accidents and injuries.

While locking pins, spring clips, and split rings might also be used in different applications or contexts for securing connections, they do not provide the same level of reliability and safety in conjunction with round pin shackles as cotter pins do. Cotter pins are specifically designed for this purpose and are a standard safety measure within the rigging industry. Understanding the critical role that cotter pins play in ensuring the integrity of the rigging system underscores their importance in maintaining safe lifting practices.