diff --git a/net_alerter/net_alerter.py b/net_alerter/net_alerter.py
index 63f7e1d..533afc9 100644
--- a/net_alerter/net_alerter.py
+++ b/net_alerter/net_alerter.py
@@ -83,7 +83,8 @@ _churn_tracker = {}       # {mac: [timestamps of departure events]}
 _churn_lock = threading.Lock()
 CHURN_THRESHOLD = 3       # cycles in window before suppression
 CHURN_WINDOW_SEC = 1800   # 30 minutes
-WATCHDOG_TIMEOUT_SEC = int(os.getenv("NET_ALERTER_WATCHDOG_TIMEOUT", "900"))
+WATCHDOG_TIMEOUT_SEC = int(os.getenv("NET_ALERTER_WATCHDOG_TIMEOUT", "180"))
+DEPARTURE_DEBOUNCE_SEC = int(os.getenv("NET_ALERTER_DEPARTURE_DEBOUNCE", "180"))
 
 # Mobile device OUI prefixes for personal device detection
 MOBILE_DEVICE_OUIS = {
@@ -1142,8 +1143,8 @@ def on_arrival(mac: str, ip: str, hostname: str = "") -> None:
 
 def on_departure(mac: str) -> None:
     """
-    Handle device departure with 15-minute debounce.
-    Only sends alert if device still gone after 15 min.
+    Handle device departure with debounce.
+    Only sends alert if device still gone after DEPARTURE_DEBOUNCE_SEC.
     """
     with known_lock:
         if mac not in known_devices:
@@ -1175,7 +1176,7 @@ def on_departure(mac: str) -> None:
         known_devices[mac]['departing'] = True
         known_devices[mac]['depart_initiated'] = time.time()
 
-    # Start 15-minute debounce timer
+    # Start departure debounce timer
     # Extract timer to cancel outside of lock to avoid deadlock
     timer_to_cancel = None
     with departure_lock:
@@ -1211,13 +1212,13 @@ def on_departure(mac: str) -> None:
             logging.info(msg)
             send_alert(msg)
 
-        timer = threading.Timer(900.0, send_departure_alert)  # 15 min = 900 sec
+        timer = threading.Timer(float(DEPARTURE_DEBOUNCE_SEC), send_departure_alert)
         timer.daemon = True
         timer.name = f'departure-debounce-{mac}'
         departure_timers[mac] = timer
         timer.start()
 
-    logging.debug(f"Departure debounce started for {mac}, will alert in 15 min if still gone")
+    logging.debug(f"Departure debounce started for {mac}, will alert in {DEPARTURE_DEBOUNCE_SEC}s if still gone")
 
 
 def get_primary_interface() -> str: