Subpart K exists because campuses are not factories
The standard hazardous waste rules assume a process that produces a known waste at a known point. A teaching laboratory produces varied small quantities at a bench, by people who are there for a semester. Subpart K is an optional alternative set of standards that eligible academic entities — colleges, universities, teaching hospitals and non-profit research institutes formally affiliated with them — may opt into for their laboratories. It replaces the usual satellite accumulation approach with a laboratory-centered regime: container requirements at the bench, a laboratory clean-out provision, and determinations made when waste leaves the laboratory rather than at the bench. Opting in is a formal act with notification and a written plan, and it is a choice rather than a default. It suits some institutions and not others, and it is worth deciding deliberately instead of discovering it exists during an inspection.