• Fingerprints (hand cream/sweat residue).
  • Materials in contact with the sample that may generate particles, e.g. paper, cardboard, polymeric foam…
  • Contact of samples with each other with the consequent risk of particle generation.
  • Identification with permanent markers/adhesive labels directly on the sample to be tested.
  • Incorrect closure of the sample bags.
  • Packaging of hot samples (risk of condensation).