diff --git a/frontend/src/components/facility3d/HierarchyBreadcrumb.tsx b/frontend/src/components/facility3d/HierarchyBreadcrumb.tsx
index 1fe3e16..18a4560 100644
--- a/frontend/src/components/facility3d/HierarchyBreadcrumb.tsx
+++ b/frontend/src/components/facility3d/HierarchyBreadcrumb.tsx
@@ -25,14 +25,15 @@ const levelIcons: Record<string, React.ReactNode> = {
 };
 
 export function HierarchyBreadcrumb({ data, onNavigate }: HierarchyBreadcrumbProps) {
-    const levels: { key: keyof BreadcrumbData; label: string }[] = [
+    const allLevels: { key: keyof BreadcrumbData; label: string }[] = [
         { key: 'facility', label: data.facility || '' },
         { key: 'building', label: data.building || '' },
         { key: 'floor', label: data.floor || '' },
         { key: 'room', label: data.room || '' },
         { key: 'section', label: data.section || '' },
         { key: 'tier', label: data.tier ? `Tier ${data.tier}` : '' },
-    ].filter(l => l.label);
+    ];
+    const levels = allLevels.filter((l): l is { key: keyof BreadcrumbData; label: string } => !!l.label);
 
     if (levels.length === 0) return null;