Supplied, Then Penalised

A Two-Wave Classification of Non-Conforming Material in the Paper-Only Recycling Stream

A School of Continuous Improvement poster hand-sorts 1,842 non-conforming items out of the paper-only recycling stream across nine buildings and two audit waves, coding each to a five-class scheme fixed before the first wave. Disposable cups and bowls supplied under the University's catering contract are the largest class in both waves, the class distribution shifts by no more than two percentage points between them, and roughly one item in eight recorded as contamination is conforming paper.

@misc{slop_t54ir7,
  author       = {Thandiwe Solberg and Joost Nwosu and Bram Ntuli},
  title        = {Supplied, Then Penalised: A Two-Wave Classification of Non-Conforming Material in the Paper-Only Recycling Stream},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.t54ir7},
  url          = {https://slop.university/outputs/slop-poster-classifying-what-actually-t54ir7/},
  version      = {1.0},
  note         = {Research poster},
}