Running a three-day conference: what changes on day two

Single-day events hide a design flaw that multi-day conferences expose immediately: most ticketing systems treat a ticket as something that is used once.

Scan it, it is spent. That works for a concert. For a three-day conference it means day two and day three are unrecordable.

Why it matters beyond tidiness

If your certificates carry CME credit, attendance is the evidence behind the credit. "Attended the conference" is not the same claim as "attended two of the three days", and if your door cannot tell the difference then neither can you when somebody asks.

The fix is structural, not a workaround: attendance is a record per **person per day**, not a flag on a ticket. One row per (ticket, day). A delegate who comes on all three days produces three rows.

What that changes at the door

The day has to be obvious and default to today. On the morning of day two, nobody should have to remember to change a dropdown. Every scan from the moment the doors open belongs to today unless somebody says otherwise.

A repeat scan is normal, not an error. Someone stepping out for tea and back is the commonest scan of the day. Showing a red cross for that teaches volunteers to ignore red crosses, which is precisely when a genuinely invalid badge walks through. A repeat should read calmly: already checked in at 09:14.

The verdict has to be readable at arm's length. The volunteer is looking at a queue, not the screen. The person's name should be the largest thing, with the outcome as a coloured badge beside it — not the other way round.

What to prepare before day one

Test the scanner on the actual phone, on the actual venue Wi-Fi, standing at the actual door. Camera permissions, the network, and the lighting all behave differently there than at your desk.

Print a few spare badges. Somebody always forgets theirs, and looking a person up by name is slower than reprinting.

Decide who is allowed to check people in, and make sure they can sign in before the queue forms, not during it.

Agree what happens when the network drops. This is the honest limitation to plan around: a door scanner that needs a connection stops working when the venue Wi-Fi does. A system that quietly pretends a scan was recorded is worse than one that says it failed — but either way, the answer is a fallback you have agreed in advance. Usually that means a printed delegate list and a pen, reconciled afterwards.

The accompanying-person trap

Multi-day events are where companion tickets go wrong. If an accompanying person is a quantity on somebody else's booking rather than a person with their own badge, then on day two you have no way to record that the delegate came and their companion did not. Give companions their own badge and their own code from the start.

Undo, and why you need it

Somebody will wave the wrong badge. A volunteer will pick the wrong day. Without a way to reverse one check-in, a mis-scan becomes permanent attendance — and on a conference that feeds certificates, permanent attendance becomes a certificate somebody did not earn.

Undo should be narrow: remove that one person on that one day, leave every other day intact. Undoing day two must not un-attend somebody who genuinely came on day one.