diff --git a/app/templates/v2/screens/admin_queue.html b/app/templates/v2/screens/admin_queue.html
index fe8c2d9..5cfd84d 100644
--- a/app/templates/v2/screens/admin_queue.html
+++ b/app/templates/v2/screens/admin_queue.html
@@ -216,16 +216,22 @@ async function refresh() {
   }
 }
 
+// Polling-Frequenz: 15s (vorher 5s) — die Queue ändert sich pro Sekunde
+// ohnehin nicht spürbar, das senkt CPU + Network ohne UX-Verlust (#183).
+var _queuePollMs = 15000;
 refresh();
-let _queueInterval = setInterval(refresh, 5000);
-// Pause-Polling wenn Tab versteckt (#183).
+let _queueInterval = setInterval(refresh, _queuePollMs);
+// Pause-Polling wenn Tab versteckt + beim Verlassen der Page (#183).
 document.addEventListener('visibilitychange', function () {
   if (document.hidden) {
     if (_queueInterval) { clearInterval(_queueInterval); _queueInterval = null; }
   } else if (!_queueInterval) {
     refresh();
-    _queueInterval = setInterval(refresh, 5000);
+    _queueInterval = setInterval(refresh, _queuePollMs);
   }
 });
+window.addEventListener('pagehide', function () {
+  if (_queueInterval) { clearInterval(_queueInterval); _queueInterval = null; }
+});
 </script>
 {% endblock %}
diff --git a/app/templates/v2/screens/admin_stand.html b/app/templates/v2/screens/admin_stand.html
index c3fcb98..4c6367a 100644
--- a/app/templates/v2/screens/admin_stand.html
+++ b/app/templates/v2/screens/admin_stand.html
@@ -330,7 +330,7 @@ async function loadStand() {
 
 loadStand();
 let _standInterval = setInterval(loadStand, 30000);
-// Pause-Polling wenn Tab versteckt (#183).
+// Pause-Polling wenn Tab versteckt + beim Verlassen der Page (#183).
 document.addEventListener('visibilitychange', function () {
   if (document.hidden) {
     if (_standInterval) { clearInterval(_standInterval); _standInterval = null; }
@@ -339,5 +339,8 @@ document.addEventListener('visibilitychange', function () {
     _standInterval = setInterval(loadStand, 30000);
   }
 });
+window.addEventListener('pagehide', function () {
+  if (_standInterval) { clearInterval(_standInterval); _standInterval = null; }
+});
 </script>
 {% endblock %}
diff --git a/app/templates/v2/screens/auswertungen.html b/app/templates/v2/screens/auswertungen.html
index 9eb8a56..f84f0bc 100644
--- a/app/templates/v2/screens/auswertungen.html
+++ b/app/templates/v2/screens/auswertungen.html
@@ -424,6 +424,22 @@ let _histChart = null;
 let _svCharts = { index: null, heuchelei: null, empfehlung: null, crossBl: null, zeitreihe: null };
 let _svMatrixAxis = 'werte'; // 'werte' or 'gruppen'
 
+// Cleanup beim Verlassen der Page (#183) — alle Charts zerstören.
+// Verhindert hängende Chart.js-Instanzen + ihre Canvas-Contexts in Memory,
+// wenn der Browser die Page nur cachet (zB. Back/Forward-Cache).
+window.addEventListener('pagehide', function () {
+  try {
+    if (_histChart) { _histChart.destroy(); _histChart = null; }
+    Object.keys(_svCharts).forEach(function (k) {
+      if (_svCharts[k]) { try { _svCharts[k].destroy(); } catch (_) {} _svCharts[k] = null; }
+    });
+    if (window._zeitreiheModalChart) {
+      try { window._zeitreiheModalChart.destroy(); } catch (_) {}
+      window._zeitreiheModalChart = null;
+    }
+  } catch (_) {}
+});
+
 function setMatrixAxis(axis) {
   _svMatrixAxis = axis;
   const werteBtn = document.getElementById('sv-axis-werte');