Looking for the Security 51 isolation decision? The official English descriptions call this checkpoint action quarantine. This guide uses that sourced term and does not treat isolation as a separate confirmed mechanic.
Isolation means quarantine here
Quarantine is a confirmed decision available at the checkpoint. Official descriptions distinguish immediate consequences from effects that may appear several shifts later, but they do not publish a complete outcome table.
Use quarantine for unresolved suspicion
Log the mismatch first: documents, permission, time, count, behavior or an anomalous observation. Quarantine is a decision under uncertainty, not proof that every unusual visitor shares the same outcome.
Track delayed outcomes
Some effects may not surface until later shifts. Exact endings, penalties and character outcomes are not yet backed by a reproducible launch-build record and are intentionally omitted.