diff --git a/ampel-firmware/sensor_console.h b/ampel-firmware/sensor_console.h
index a1859b9d26b20d2dc413d092bd74d2641dce1e15..0434d484efef93a7c603b63e00bf42f0dc1553b7 100644
--- a/ampel-firmware/sensor_console.h
+++ b/ampel-firmware/sensor_console.h
@@ -1,3 +1,5 @@
+#ifndef SENSOR_CONSOLE_H_INCLUDED
+#define SENSOR_CONSOLE_H_INCLUDED
 #include <Arduino.h>
 
 /** Other scripts can use this namespace, in order to define commands, via callbacks.
@@ -11,3 +13,5 @@ namespace sensor_console {
   void defineIntCommand(const char *command, void (*function)(int32_t), const char *doc);
   void defineCommand(const char *command, void (*function)(void), const char *doc);
 }
+
+#endif