Why we freeze it
The presence list is frozen the moment the incident opens, and later movement is kept separately. The two lists are never merged: if everyone who walks out of the gate during the evacuation drops off the list, the number on screen shrinks and it starts to look as if no search is needed.
Three states, two are not enough
A missing record cannot be closed without the last gate and time; it is the only concrete fact a search team can be given.
- Safe: the person was marked at the assembly point.
- Injured: the person was found and needs medical support.
- Missing: the person has not been found; the record is kept with the last gate and time.
Self-reporting at the assembly point
A person can mark themselves safe by scanning a QR code; several stations see the same list, so the same person is not counted twice across two points.
A drill runs in the same flow
A drill does not run on a separate screen: it runs in the same flow and its duration is measured. An unmeasured drill only tells you it happened; a measured drill shows you where you waited.