diff --git a/app.py b/app.py
index 78bca29..e736770 100644
--- a/app.py
+++ b/app.py
@@ -69,7 +69,7 @@ def load_config() -> Settings:
 
     try:
         db_port = int(os.environ["SUPABASE_DB_PORT"])
-        ping_interval = int(os.environ.get("PING_INTERVAL_MINUTES", "4320"))
+        ping_interval = float(os.environ.get("PING_INTERVAL_MINUTES", "4320"))
         web_port = int(os.environ.get("WEB_PORT", "8080"))
         retention_hours = int(os.environ.get("RRD_RETENTION_HOURS", "48"))
         if ping_interval <= 0 or web_port <= 0 or retention_hours <= 0:
@@ -77,7 +77,7 @@ def load_config() -> Settings:
     except ValueError as exc:
         raise RuntimeError(
             "SUPABASE_DB_PORT, PING_INTERVAL_MINUTES, WEB_PORT e "
-            "RRD_RETENTION_HOURS devono essere interi positivi."
+            "RRD_RETENTION_HOURS devono essere numeri positivi."
         ) from exc
 
     return Settings(