diff --git a/scintillation/averaging.py b/scintillation/averaging.py
index 09859a032a1c11688c81c9b20f2e16d7bb87dc9a..9c67824cda45a4f031f864c05bd86888021a10d4 100644
--- a/scintillation/averaging.py
+++ b/scintillation/averaging.py
@@ -109,6 +109,8 @@ class SmartJsonEncoder(json.JSONEncoder):
                 return o.tolist()
             elif isinstance(o, numpy.uint64):
                 return int(o)
+            elif isinstance(o, numpy.uint32):
+                return int(o)
             elif isinstance(o, datetime):
                 return o.isoformat()
             else: