I am an Instructional Designer and am currently developing DeltaV training for Genentech OCN, and have a question - When is it appropriate to abort a batch in the BOI? I need a list of circumstances or events that cause an operator to abort a batch, and some examples would be great too! Thanks for your help!
The ISA S88 Standard describes abort as:
— ABORTING: The procedural element has received an ABORT command and is
executing its ABORT logic, which is the logic that facilitates a quicker, but not necessarily
controlled, abnormal stop. If no sequencing is required, then the procedural element
transitions immediately to the ABORTED state.
DeltaV Books on line describes abort as :
Abort - This command invokes the aborting logic for applicable phases of a batch, to reach the aborted state. The operator cannot restart a batch after an abort command. Abort is an emergency stop.
I'm not sure I completely agree with the latter, after all, hitting the physical emergency stop on a piece of processing equipment shouldn't necessarily equate with aborting the batch. Abort is unrecoverable, so it can have an immediate adverse financial, compliance, or quality impact on the batch product. Hold is more often practiced as the failsafe or emergency stop response, because it is recoverable. Abort is distinguished from Stop due to it's abnormal nature, (stop can be valid and expected way to end a batch).
I have not seen in the pharmaceutical industry a case where operators would abort a batch representing product manufacture without weigh-in from various other departments, as the cost associated with such an action should be recognized and agreed upon by all stakeholders. When batch processing for cleaning or steaming, abort is more commonly used by the operations staff to flag these activities as failed in preparation for starting over (perhaps after a maintenance or equipment issue has been addressed). A cleaning or steaming abort is a small loss compared to aborting product processing, and could lead to product loss if not aborted and re-executed correctly.
Usually, a batch is aborted when there is little to lose - no product in the tank yet, but perhaps pressure check has failed, or scheduling conflicts prevent proceeding with the batch as defined. In a semi-continuous process, where multiple successful sub batches of product have been produced, but the WIP product is suspect, consideration as to whether an aborted status on the overall batch could be detrimental to successfully produced sub batches should be taken. In these scenarios, a stop may be more appropriate.