Don't take the risk with aged and damaged tippet. - It is probably time for a refresh.
"I knew I should have bought new tippet... you wouldn't believe the fish I lost, it just broke me right off."
To say we hear that a few times a year, usually with a few more 4-letter words, is an understatement!
Old tippet means weakened tippet. Both nylon and fluorocarbon age (nylon much faster than fluorocarbon), and age does take its toll, especially once exposed to nature's elements.
Monofilament, often referred to as 'mono', stored tightly on spools ends up forming to the shape of the spool; we call this memory, and it can be easily seen in the coils after you remove monofilament from any spool. That memory gets more difficult to remove the older the material is. A fresh spool of tippet will have far less memory than any aged spool, and it usually can be straightened simply by running the line through pinched fingers or a leader straightener, If it is older material it may take multiple attempts, or may not straighten at all.
Breaking strengths of monofilament are greatly reduced through age, improper storage, high temperatures, and exposure to UV light. So, if your tippet and leaders have been out on the water exposed to the sun, stashed with your gear in the trunk of your car parked during the summer, and were bought early last year, you're due for a change.
When you're sorting through your gear this season and find old spools of tippet more than a year old (and especially the lighter weights), do yourself a favour and re-purpose them.
We have the privilege in the shop of reviewing many people's gear with them and we often find spools of tippet that have not been produced in this decade. It doesn't take long to convince the angler that their best bet is to chuck the old stuff and grab a new spool of tippet and leaders after we take a length of line off their aged spool and break it consistently below its rated weight.