They can be sizable depending on the type or how many fibers are run. Marine vs terrestrial are different as well. Repair depends on the type of cut, too. Ae

They can be sizable depending on the type or how many fibers are run. Marine vs terrestrial are different as well. Repair depends on the type of cut, too. Aerial run? Buried? Did the fiber get damaged as a result of an underground gas explosion in a nearby vault that caused several meters to fuse together? :) Often, a splicing is necessary - that involves using special equipment to re-align and fuse the damaged pairs. Slack in the run can be used to bring the damaged ends flush, or a segment can be added to couple them.