The same three questions keep landing in our inbox.
"How do we set the acceptance limit for the peel test?"
"When do we have to repeat the validation?"
"I'm using the same packaging material for different pack sizes on different machines. Do I really need to validate each one?"
They come from packaging engineers, from quality managers, from people preparing for an audit next month. Different companies, same three questions. So we wrote the answers down.
On the peel limit: it has to be two-sided, and it has to come from your own data. Too weak and the seal opens in distribution. Too strong and the nurse cannot peel it cleanly, tears the porous web, and showers fibers over the sterile field. Both are patient harms. A specification with only a minimum controls one of them. And the EN 868-5 numbers everyone reaches for apply to pouches supplied to hospitals, not to industrial packaging.
On repeating validation: the triggers are written down in ISO 11607-1 Clause 9 and ISO 11607-2 Clause 5.7, and one of them surprises people. A negative trend in a quality or process indicator is a trigger in its own right. You do not wait for a failure.
On different machines and pack sizes: a new machine always needs a new validation. Everything else can usually be bracketed into a family, but sharing a material is not enough on its own. What matters is seal area, seal geometry, device mass and bulk, and what the operator has to handle. ISO/TS 16775 works through exactly this case, including a second identical machine.
Twelve questions in total, each answered against the clause that governs it. Where the standard is silent, we say so.