diff --git a/rxnlvl/__init__.py b/rxnlvl/__init__.py
index e32e638..b71d2b7 100644
--- a/rxnlvl/__init__.py
+++ b/rxnlvl/__init__.py
@@ -68,7 +68,6 @@ def __init__(self, dimensions, bgcolour=None, vbuf=10.0, hbuf=10.0,
             )
         except AssertionError as e:
             sys.stderr.write(str(e))
-            sys.exit(1)
         self.qualified = qualified
         try:
             assert vbuf > 0 and hbuf > 0,\