What the classification says
Unacceptable components have clearly been used (e.g. boards that are too thin, blocks that are too small).
How to spot it
Measure a suspect board: EPAL 1 boards should be 22–24 mm thick (stringers up to 25 mm). Undersized blocks, rotten parts or boards with wane are the poster's examples.
Why it matters
This defect covers parts that were never right for an EPAL pallet: boards that are too thin, blocks that are too small, rotten parts, or boards with wane, the rounded edge where bark was. It usually means someone replaced parts with whatever timber was at hand. EPAL 1 boards are specified at 22 to 24 mm, with stringer boards up to 25 mm, and poplar is not permitted for stringers. A caliper and a tape measure are enough to check, and a mismatched part is strong evidence of an unlicensed repair.
Effect on the pallet's class
Not fit for use. Usually a sign of an unlicensed repair. See Not fit for use for the full criteria.
Repair
A licensed repairer replaces the part with a compliant one.
If no licensed repairer is practical, sell sound timber as non-EPAL wood or send the pallets for recycling.