diff --git a/schemas/geomprimitives.schema.json b/schemas/geomprimitives.schema.json
index 519e732..b16ccce 100644
--- a/schemas/geomprimitives.schema.json
+++ b/schemas/geomprimitives.schema.json
@@ -109,6 +109,15 @@
       "type"
     ]
   },
+  "Lods": {
+      "enum": [
+        "0",   "1",   "2",   "3", 
+        "0.0", "0.1", "0.2", "0.3", 
+        "1.0", "1.1", "1.2", "1.3", 
+        "2.0", "2.1", "2.2", "2.3", 
+        "3.0", "3.1", "3.2", "3.3"
+      ]
+  },
   "Solid": {
     "type": "object",
     "properties": {
@@ -118,8 +127,7 @@
         ]
       },
       "lod": {
-        "type": "string",
-        "pattern": "^(\\d\\.)(\\d)$|^(\\d)$"
+        "$ref": "#/Lods" 
       },
       "boundaries": {
         "type": "array",
@@ -257,8 +265,7 @@
         ]
       },
       "lod": {
-        "type": "string",
-        "pattern": "^(\\d\\.)(\\d)$|^(\\d)$"
+        "$ref": "#/Lods" 
       },
       "boundaries": {
         "type": "array",
@@ -415,8 +422,7 @@
         ]
       },
       "lod": {
-        "type": "string",
-        "pattern": "^(\\d\\.)(\\d)$|^(\\d)$"
+        "$ref": "#/Lods" 
       },
       "boundaries": {
         "type": "array",
@@ -573,8 +579,7 @@
         ]
       },
       "lod": {
-        "type": "string",
-        "pattern": "^(\\d\\.)(\\d)$|^(\\d)$"
+        "$ref": "#/Lods" 
       },
       "boundaries": {
         "type": "array",
@@ -693,8 +698,7 @@
         ]
       },
       "lod": {
-        "type": "string",
-        "pattern": "^(\\d\\.)(\\d)$|^(\\d)$"
+        "$ref": "#/Lods" 
       },
       "boundaries": {
         "type": "array",
@@ -813,8 +817,7 @@
         ]
       },
       "lod": {
-        "type": "string",
-        "pattern": "^(\\d\\.)(\\d)$|^(\\d)$"
+        "$ref": "#/Lods" 
       },
       "boundaries": {
         "type": "array",
@@ -871,8 +874,7 @@
         ]
       },
       "lod": {
-        "type": "string",
-        "pattern": "^(\\d\\.)(\\d)$|^(\\d)$"
+        "$ref": "#/Lods" 
       },
       "boundaries": {
         "type": "array",