diff --git a/control/json/fan.hpp b/control/json/fan.hpp
index cac8dd2..06c301d 100644
--- a/control/json/fan.hpp
+++ b/control/json/fan.hpp
@@ -61,7 +61,7 @@
      *
      * @param[in] jsonObj - JSON object
      */
-    Fan(const json& jsonObj);
+    explicit Fan(const json& jsonObj);
 
     /**
      * @brief Get the zone