What is the minimum amount of slack that should be provided for splicing fiber-optic cable in underground installations?

Providing enough slack fiber-optic cable is crucial for both the installation and future maintenance or repairs. The specified minimum amount of slack for splicing in underground installations is typically based on the need to accommodate potential length changes due to environmental factors, ease of handling, and ensuring there is enough cable to work with without causing damage during splicing or other operations.

The option indicating 15 meters of slack on both the inbound and outbound spans is important because it allows technicians to splice the fibers properly and ensures there's enough cable available to handle adjustments or repositioning of the fibers in case of future needs. Having this amount of slack also helps prevent excessive tension on the fibers during installation or as a result of ground movement, which can lead to cable breakage or impairment of the signal.

Other choices provide differing amounts of slack but may not meet industry standards for ensuring reliable splicing and future access to the cable. For instance, slack amounts less than 15 meters might restrict movement and increase the risk of damage to the cables themselves during future maintenance. Thus, the minimum guideline of 15 meters on both spans is designed for optimal operational efficiency and safety, aligning with best practices in the industry.