diff --git a/.replit b/.replit
index 90b1d94..b6a9521 100644
--- a/.replit
+++ b/.replit
@@ -39,6 +39,10 @@ externalPort = 5000
 localPort = 43267
 externalPort = 3003
 
+[[ports]]
+localPort = 44575
+externalPort = 5173
+
 [env]
 PORT = "5000"
 
diff --git a/server/routes.ts b/server/routes.ts
index bcc19b1..48c0ea6 100644
--- a/server/routes.ts
+++ b/server/routes.ts
@@ -1326,6 +1326,7 @@ export async function registerRoutes(app: Express): Promise<Server> {
             .from(shiftAssignments)
             .where(eq(shiftAssignments.guardId, guard.id));
           
+          // Check for time overlaps
           for (const existing of existingAssignments) {
             const hasOverlap = 
               plannedStart < existing.plannedEndTime && 
@@ -1338,6 +1339,34 @@ export async function registerRoutes(app: Express): Promise<Server> {
             }
           }
           
+          // CCNL: Check daily hour limit (max 9h/day)
+          const maxDailyHours = 9;
+          let dailyHoursAlreadyAssigned = 0;
+          
+          for (const existing of existingAssignments) {
+            // Check if assignment is on the same day
+            const existingDate = new Date(existing.plannedStartTime);
+            if (
+              existingDate.getUTCFullYear() === actualYear &&
+              existingDate.getUTCMonth() === actualMonth &&
+              existingDate.getUTCDate() === actualDay
+            ) {
+              const assignmentHours = differenceInHours(
+                existing.plannedEndTime,
+                existing.plannedStartTime
+              );
+              dailyHoursAlreadyAssigned += assignmentHours;
+            }
+          }
+          
+          // Check if new assignment would exceed daily limit
+          if (dailyHoursAlreadyAssigned + durationHours > maxDailyHours) {
+            throw new Error(
+              `Limite giornaliero superato: la guardia ha già ${dailyHoursAlreadyAssigned}h assegnate il ${shiftDate.toLocaleDateString('it-IT')}. ` +
+              `Aggiungendo ${durationHours}h si supererebbero le ${maxDailyHours}h massime giornaliere (CCNL).`
+            );
+          }
+          
           // Create assignment for this day
           const [assignment] = await tx.insert(shiftAssignments).values({
             shiftId: shift.id,