UV Degradation Solutions for Running Shorts: Specification Checklist
Use this checklist to write uv degradation requirements for running shorts into a tech pack that a mill can quote against.
Targets to fix before sampling
Write UPF above 50 after 40 hours exposure into the pack. Mills quote against the number on the page, so vague language leads to variable results. Because high cadence movement plus perspiration at the waistband, target checks are made on a worn sample rather than flat fabric alone.
Fabric construction
State structure, composition and finish together. Typical options for this build are lightweight woven or knit body with a knit liner, adjusted to the performance level required. Keep AATCC 183 UPF and ISO 105-B02 light fastness named in the tech pack so every lot is measured the same way.
Seam and trim requirements
The problem shows as colour fading and strength loss after sun exposure. Construction choices either remove the cause or hide it for a few washes, so specify the method instead of the outcome. Where running shorts is worn for road, trail and track training, set tolerances around that range of movement.
Laboratory to request
Ask for AATCC 183 UPF and ISO 105-B02 light fastness on every shade and every size run, not only the approval sample. Any change to lightweight woven or knit body with a knit liner requires re-testing against UPF above 50 after 40 hours exposure before bulk is released.
Acceptance criteria
Agree the limit before sampling starts. Re-testing after disagreement costs more than setting the target clearly at the beginning. Past reports from AATCC 183 UPF and ISO 105-B02 light fastness help the mill reproduce the same recipe on the next order.
