diff --git a/rocketpy/tools.py b/rocketpy/tools.py
index 136a82a57..d0a017fae 100644
--- a/rocketpy/tools.py
+++ b/rocketpy/tools.py
@@ -398,12 +398,10 @@ def is_float(element):
     result : boolean
         The element is convertible or not.
     """
-    if element is None:
-        return False
     try:
         float(element)
         return True
-    except ValueError:
+    except (ValueError, TypeError):
         return False