An adulteration limit of 100 ?g/25cm? (4 ?g/cm?) was proposed for pilot-plant facilities. The dynamic changes in equipment, formulation, and residue determination made implementation of a constantly changing, calculated adulteration limit impractical. A single adulteration limit was simpler to communicate and document, making compliance achievable. The limit would be used only after it was determined to be lower than a health-based evaluation and a visual-cleanliness assessment.
