diff --git a/src/nt/ntndarray.cpp b/src/nt/ntndarray.cpp
index e3aef97..4b8233f 100644
--- a/src/nt/ntndarray.cpp
+++ b/src/nt/ntndarray.cpp
@@ -25,109 +25,64 @@ static PVDataCreatePtr pvDataCreate = getPVDataCreate();
 
 StructureConstPtr NTNDArrayBuilder::createStructure()
 {
-    enum
+    StandardFieldPtr standardField = getStandardField();
+    FieldBuilderPtr fb = fieldCreate->createFieldBuilder();
+
+    for (int i = pvBoolean; i < pvString; ++i)
     {
-        DISCRIPTOR_INDEX,
-        TIMESTAMP_INDEX,
-        ALARM_INDEX,
-        DISPLAY_INDEX
-    };
-
-    const size_t NUMBER_OF_INDICES = DISPLAY_INDEX+1;
-    const size_t NUMBER_OF_STRUCTURES = 1 << NUMBER_OF_INDICES;
-
-    static epics::pvData::StructureConstPtr ntndarrayStruc[NUMBER_OF_STRUCTURES];
-    static epics::pvData::UnionConstPtr valueType;
-    static epics::pvData::StructureConstPtr codecStruc;
-    static epics::pvData::StructureConstPtr dimensionStruc;
-    static epics::pvData::StructureConstPtr attributeStruc;
-
-    static Mutex mutex;
-
-    Lock xx(mutex);
-
-    size_t index = 0;
-    if (descriptor) index  |= 1 << DISCRIPTOR_INDEX;
-    if (timeStamp)  index  |= 1 << TIMESTAMP_INDEX;
-    if (alarm)      index  |= 1 << ALARM_INDEX;
-    if (display)    index  |= 1 << DISPLAY_INDEX;
-
-    if (!ntndarrayStruc[index])
-    {
-        StandardFieldPtr standardField = getStandardField();
-        FieldBuilderPtr fb = fieldCreate->createFieldBuilder();
-
-        if (!valueType)
-        {
-            for (int i = pvBoolean; i < pvString; ++i)
-            {
-                ScalarType st = static_cast<ScalarType>(i);
-                fb->addArray(std::string(ScalarTypeFunc::name(st)) + "Value", st);
-            }
-            valueType = fb->createUnion();                
-        }
-
-        if (!codecStruc)
-        {
-            codecStruc = fb->setId("codec_t")->
-                add("name", pvString)->
-                add("parameters", fieldCreate->createVariantUnion())->
-                createStructure();
-        }
-
-        if (!dimensionStruc)
-        {
-            dimensionStruc = fb->setId("dimension_t")->
-                add("size", pvInt)->
-                add("offset",  pvInt)->
-                add("fullSize",  pvInt)->
-                add("binning",  pvInt)->
-                add("reverse",  pvBoolean)->
-                createStructure();
-        }
-
-        if (!attributeStruc)
-        {
-            attributeStruc = fb->setId(ntAttrStr)->
-		        add("name", pvString)->
-			    add("value", fieldCreate->createVariantUnion())->
-			    add("descriptor", pvString)->
-                add("sourceType", pvInt)->
-                add("source", pvString)->
-               createStructure();
-        }
-
-        fb->setId(NTNDArray::URI)->
-            add("value", valueType)->
-            add("codec", codecStruc)->
-            add("compressedSize", pvLong)->
-            add("uncompressedSize", pvLong)->
-            addArray("dimension", dimensionStruc)->
-            add("uniqueId", pvInt)->
-            add("dataTimeStamp", standardField->timeStamp())->
-            addArray("attribute", attributeStruc);
-
-        if (descriptor)
-            fb->add("descriptor", pvString);
-
-        if (timeStamp)
-            fb->add("timeStamp", standardField->timeStamp());
-
-        if (alarm)
-            fb->add("alarm", standardField->alarm());
-
-        if (display)
-            fb->add("display", standardField->display());
-
-        size_t extraCount = extraFieldNames.size();
-        for (size_t i = 0; i< extraCount; i++)
-            fb->add(extraFieldNames[i], extraFields[i]);
-
-
-        ntndarrayStruc[index] = fb->createStructure();
+        ScalarType st = static_cast<ScalarType>(i);
+        fb->addArray(std::string(ScalarTypeFunc::name(st)) + "Value", st);
     }
+    UnionConstPtr valueType = fb->createUnion();                
 
-    return ntndarrayStruc[index];
+    StructureConstPtr codecStruc = fb->setId("codec_t")->
+        add("name", pvString)->
+        add("parameters", fieldCreate->createVariantUnion())->
+        createStructure();
+
+    StructureConstPtr dimensionStruc = fb->setId("dimension_t")->
+        add("size", pvInt)->
+        add("offset", pvInt)->
+        add("fullSize", pvInt)->
+        add("binning", pvInt)->
+        add("reverse", pvBoolean)->
+        createStructure();
+
+    StructureConstPtr attributeStruc = fb->setId(ntAttrStr)->
+        add("name", pvString)->
+        add("value", fieldCreate->createVariantUnion())->
+        add("descriptor", pvString)->
+        add("sourceType", pvInt)->
+        add("source", pvString)->
+       createStructure();
+
+    fb->setId(NTNDArray::URI)->
+        add("value", valueType)->
+        add("codec", codecStruc)->
+        add("compressedSize", pvLong)->
+        add("uncompressedSize", pvLong)->
+        addArray("dimension", dimensionStruc)->
+        add("uniqueId", pvInt)->
+        add("dataTimeStamp", standardField->timeStamp())->
+        addArray("attribute", attributeStruc);
+
+    if (descriptor)
+        fb->add("descriptor", pvString);
+
+    if (timeStamp)
+        fb->add("timeStamp", standardField->timeStamp());
+
+    if (alarm)
+        fb->add("alarm", standardField->alarm());
+
+    if (display)
+        fb->add("display", standardField->display());
+
+    size_t extraCount = extraFieldNames.size();
+    for (size_t i = 0; i< extraCount; i++)
+        fb->add(extraFieldNames[i], extraFields[i]);
+
+    return fb->createStructure();
 }
 
 NTNDArrayBuilder::shared_pointer NTNDArrayBuilder::addDescriptor()