Prepared material and working charge
Prepared material is what the team makes available for the run. Minimum working charge is the amount needed to operate the actual vessel and circuit under the stated procedure. It depends on the chosen configuration and operating sequence, so it cannot be inferred from vessel capacity or another model's small-batch claim.
Inventory and unrecovered material
Circuit hold-up is the product contained in the named path at a stated condition. Some may later leave the circuit; some may remain at shutdown. Record terminal material left in that circuit separately from its full inventory. If the vessel heel or handling loss lies outside that circuit, put it in a clearly separate allowance.
Discard and representative output
Startup discard covers material used before the agreed collection state. Transition discard covers changes between conditions. Steady output is all material leaving during the accepted stable window; labelled analytical samples are only part of it. Do not add sample volume a second time after accounting for steady output.
Product and cleaning supplies
Cleaning water and chemicals are separate requirements. A product-water interface that cannot be used belongs in a named product-discard category, with its measurement basis clear. Ask for a configuration-specific trial-volume account rather than a single unexplained minimum number.