French term (edited): jauge de remplissage

"jauge de remplissage" is about measuring how much the venue is already filled, as the public is being admitted - literally:
"filled capacity indicator" or "used capacity indicator"

in fact what's really meant is:

"remaining / available capacity indicator" but you can't put that it the count starts at 0 % and moves towards 100 %

Namely, between opening the doors and starting the show, what needs to be monitored is the remaining capacity - to avoid ending up with numbers over the venue's capacity.


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Note added at 2 days23 hrs (2014-02-19 14:36:27 GMT)
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ST: "Logiciel de gestion de contrôle d’accès
Pilotage en temps réel du contrôle d’accès : compostage, jauge de remplissage, gestion des zones…"

The "remplissage" is about the public getting into the venue before the start of the show, not about filling available places by selling them.