diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/search/detailed/DetailedQueryBuilder.java b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/search/detailed/DetailedQueryBuilder.java
index 0c9808afd549dd356e8bfbf59ef6a12fa54fe205..558cf903036a7668c136bc3ead5df3336bf32057 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/search/detailed/DetailedQueryBuilder.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/search/detailed/DetailedQueryBuilder.java
@@ -121,7 +121,7 @@ public class DetailedQueryBuilder
                                 LuceneQueryBuilder.adaptQuery(fieldUserQuery,
                                         useWildcardSearchMode, false);
                         fieldAnalyzer = new IgnoreCaseAnalyzer();
-                    } else if(isNumeric)
+                    } else if(isNumeric && criterion.getType() != null)
                     {
                         String parsedNumberValue = SortableNumberBridgeUtils.getNumberForLucene(criterion.getValue());
                         switch(criterion.getType()) {