Containment projects often begin with a target OEL and a list of isolated equipment features. The stronger starting point is a material-transfer map covering dispensing, charging, processing, sampling, discharge, cleaning, waste, and maintenance.
Define the operating states
Normal production, changeover, upset recovery, filter handling, and maintenance each create different boundaries. A system that performs during steady operation can still fail the exposure strategy during intervention.
Assign a control principle to every opening
Closed transfer, local extraction, split valves, glove access, wet methods, and procedural controls each have a place. Selection should follow the material route and the credible failure mode.
Test the interfaces together
Surrogate testing should include the actual transfer sequence, operator actions, extraction state, and cleaning method. Interfaces belong in the FAT because they are part of the system performance.