diff --git a/src/paveit/datamodels/norm_specification.py b/src/paveit/datamodels/norm_specification.py
index 96f3689..dc79713 100644
--- a/src/paveit/datamodels/norm_specification.py
+++ b/src/paveit/datamodels/norm_specification.py
@@ -1,6 +1,6 @@
 from mongoengine import *
 
-from .enumeration import RelationalOperatorsEnum, BitumenCategoryEnum
+from .enumeration import RelationalOperatorsEnum, BitumenCategoryEnum, AsphaltCategoryEnum
 from .norm_documents import NormDocumentAggregate, NormDocumentBitumen, NormDocumentAsphalt
 
 from paveit.helper import fetch_recursive, mongo_to_dict
@@ -97,7 +97,7 @@ class AsphaltParameterLimitsBaseEnum(EnumerateBase):
 class AsphaltParameterLimitsAsphalttragschicht(AsphaltParameterLimitsBaseEnum):
     
     name = StringField()
-    category = EnumField(BitumenCategoryEnum, required=True)
+    category = EnumField(AsphaltCategoryEnum, required=True)
     norm =  LazyReferenceField(NormDocumentBitumen, required=True)