Katsu

Official wording

Non-food contact surface or equipment made of unacceptable material, not kept clean, or not properly sealed, raised, spaced or movable to allow accessibility for cleaning on all sides, above and underneath the unit.

In plain English

Dishes, equipment, or surfaces that touch food were not properly washed, rinsed, and sanitized, or sanitizer was not at the right strength. Clean surfaces help stop germs from spreading to food.