Safety Lines with Flags?!
We used safety belts on a square rigged ship I used to work for that had the tethers that were stitched to provide a "shock absorber" effect if you exceed an amount of force. The tether would break the stitching and lengthen, showing a warning message with an orange box around it. This message meant that the tethers "Shock absorber" feature had been used and the tether should not be used because the feature was no longer available. (Save your old tether. They work well if modified to keep tools from falling when working aloft.)