diff --git a/Detector/DetCRD/compact/CRD_common_v01/DC_Simple_v01_01.xml b/Detector/DetCRD/compact/CRD_common_v01/DC_Simple_v01_01.xml
index 44f21025ccffe4e952544a836af318c54e56cd6e..437706b53400d634c49d5d1e13ec15f79416d046 100644
--- a/Detector/DetCRD/compact/CRD_common_v01/DC_Simple_v01_01.xml
+++ b/Detector/DetCRD/compact/CRD_common_v01/DC_Simple_v01_01.xml
@@ -14,18 +14,16 @@
     <constant name="SDT_radius_min" value="InnerTracker_inner_radius"/>
     <constant name="SDT_radius_max" value="OuterTracker_outer_radius"/>
 
-    <constant name="SDT_half_length" value="DC_half_length"/>
+    <constant name="SDT_half_length" value="MainTracker_half_length"/>
     <constant name="SDT_length" value="SDT_half_length*2"/>
     <constant name="DC_length" value="DC_half_length*2"/>
 
-    <constant name="SDT_chamber_inner_wall_thickness" value="0.2*mm"/>
-    <constant name="SDT_chamber_outer_wall_thickness" value="2.8*mm"/>
-    <constant name="SDT_inner_chamber_radius_min" value="InnerTracker_inner_radius+SDT_chamber_inner_wall_thickness"/>
-    <constant name="SDT_inner_chamber_radius_max" value="InnerTracker_outer_radius-SDT_chamber_outer_wall_thickness"/>
+    <constant name="SDT_inner_chamber_radius_min" value="235*mm-DC_safe_distance"/>
+    <constant name="SDT_inner_chamber_radius_max" value="InnerTracker_outer_radius"/>
     <constant name="SDT_inner_chamber_length" value="DC_length"/>
 
-    <constant name="SDT_outer_chamber_radius_min" value="OuterTracker_inner_radius+SDT_chamber_inner_wall_thickness"/>
-    <constant name="SDT_outer_chamber_radius_max" value="OuterTracker_outer_radius-SDT_chamber_outer_wall_thickness"/>
+    <constant name="SDT_outer_chamber_radius_min" value="OuterTracker_inner_radius"/>
+    <constant name="SDT_outer_chamber_radius_max" value="1715*mm+DC_safe_distance"/>
     <constant name="SDT_outer_chamber_length" value="DC_length"/>
 
     <constant name="SDT_inner_chamber_layer_number" value="67"/>
@@ -33,14 +31,14 @@
     <constant name="SDT_chamber_layer_width" value="10*mm"/>
     <constant name="Epsilon" value="0*deg"/>
 
-    <constant name="SDT_inner_chamber_inner_wall_radius_min" value="SDT_inner_chamber_radius_min-SDT_chamber_inner_wall_thickness"/>
-    <constant name="SDT_inner_chamber_inner_wall_radius_max" value="SDT_inner_chamber_radius_min"/>
-    <constant name="SDT_inner_chamber_outer_wall_radius_min" value="SDT_inner_chamber_radius_max"/>
-    <constant name="SDT_inner_chamber_outer_wall_radius_max" value="SDT_inner_chamber_radius_max+SDT_chamber_outer_wall_thickness"/>
-    <constant name="SDT_outer_chamber_inner_wall_radius_min" value="SDT_outer_chamber_radius_min-SDT_chamber_inner_wall_thickness"/>
-    <constant name="SDT_outer_chamber_inner_wall_radius_max" value="SDT_outer_chamber_radius_min"/>
-    <constant name="SDT_outer_chamber_outer_wall_radius_min" value="SDT_outer_chamber_radius_max"/>
-    <constant name="SDT_outer_chamber_outer_wall_radius_max" value="SDT_outer_chamber_radius_max+SDT_chamber_outer_wall_thickness"/>
+    <constant name="SDT_inner_chamber_inner_wall_radius_min" value="234.6*mm"/>
+    <constant name="SDT_inner_chamber_inner_wall_radius_max" value="234.8*mm"/>
+    <constant name="SDT_inner_chamber_outer_wall_radius_min" value="906*mm"/>
+    <constant name="SDT_inner_chamber_outer_wall_radius_max" value="908.8*mm"/>
+    <constant name="SDT_outer_chamber_inner_wall_radius_min" value="1084*mm"/>
+    <constant name="SDT_outer_chamber_inner_wall_radius_max" value="1084.2*mm"/>
+    <constant name="SDT_outer_chamber_outer_wall_radius_min" value="1716*mm"/>
+    <constant name="SDT_outer_chamber_outer_wall_radius_max" value="1718.8*mm"/>
 
     <constant name="DC_Endcap_rmin" value="SDT_radius_min"/>
     <constant name="DC_Endcap_rmax" value="SDT_radius_max"/>
@@ -57,8 +55,8 @@
     <detector id="DetID_DC" name="DriftChamber" type="DriftChamber" readout="DriftChamberHitsCollection" vis="BlueVis" sensitive="true" insideTrackingVolume="true">
       <envelope vis="SeeThrough">
         <shape type="BooleanShape" operation="Union" material="Air">
-          <shape type="Tube" rmin="SDT_radius_min" rmax="InnerTracker_outer_radius" dz="MainTracker_half_length" />
-          <shape type="Tube" rmin="OuterTracker_inner_radius" rmax="SDT_radius_max" dz="MainTracker_half_length" />
+          <shape type="Tube" rmin="SDT_radius_min" rmax="909*mm" dz="SDT_half_length" />
+          <shape type="Tube" rmin="SDT_outer_chamber_inner_wall_radius_min" rmax="SDT_radius_max" dz="SDT_half_length" />
         </shape>
       </envelope>
 
@@ -80,7 +78,7 @@
 
   <readouts>
     <readout name="DriftChamberHitsCollection">
-      <segmentation type="GridDriftChamber" cell_size="10*mm" epsilon0="Epsilon" detector_length="DC_length" identifier_phi="cellID" />
+      <segmentation type="GridDriftChamber" cell_size="10*mm" epsilon0="Epsilon" detector_length="DC_length" identifier_phi="cellID" DC_inner_rmin="SDT_inner_chamber_radius_min" DC_inner_rmax="SDT_inner_chamber_radius_max" DC_outer_rmin="SDT_outer_chamber_radius_min" DC_outer_rmax="SDT_outer_chamber_radius_max" layerID="layer"/>
 
       <id>system:8,chamber:1,layer:8,cellID:16</id>
     </readout>
diff --git a/Detector/DetCRD/compact/CRD_o1_v01/CRD_Dimensions_v01_01.xml b/Detector/DetCRD/compact/CRD_o1_v01/CRD_Dimensions_v01_01.xml
index 7fa9b7cba6c11d4e29037539f4dddd8a50181b20..ab7bb56c75e83593109af5a19d291dfa96b9b455 100644
--- a/Detector/DetCRD/compact/CRD_o1_v01/CRD_Dimensions_v01_01.xml
+++ b/Detector/DetCRD/compact/CRD_o1_v01/CRD_Dimensions_v01_01.xml
@@ -83,13 +83,14 @@
 
     <constant name="DC_Endcap_z" value="0.1*mm"/>
     <constant name="DC_half_length"  value="2225*mm" />
+    <constant name="DC_safe_distance" value="0.02*mm"/>
     <constant name="MainTracker_half_length"  value="DC_half_length+DC_Endcap_z" />
     <constant name="InnerTracker_half_length"  value="DC_half_length" />
-    <constant name="InnerTracker_inner_radius" value="234.8*mm"/>
-    <constant name="InnerTracker_outer_radius" value="908.8*mm"/>
+    <constant name="InnerTracker_inner_radius" value="234*mm"/>
+    <constant name="InnerTracker_outer_radius" value="906*mm"/>
     <constant name="OuterTracker_half_length"  value="DC_half_length"/>
-    <constant name="OuterTracker_inner_radius" value="1084.8*mm"/>
-    <constant name="OuterTracker_outer_radius" value="1717.8*mm"/>
+    <constant name="OuterTracker_inner_radius" value="1085*mm-DC_safe_distance"/>
+    <constant name="OuterTracker_outer_radius" value="1720*mm"/>
     
     <constant name="SIT1_inner_radius"   value="152.90*mm"/>
     <constant name="SIT1_half_length"    value="368.00*mm"/>
diff --git a/Detector/DetDriftChamber/compact/det.xml b/Detector/DetDriftChamber/compact/det.xml
index bf4e197d8689e4f8dfca152fe3efdb9b76c9760b..55176dae881f3a5778c6087da55adb1e4c4e0761 100644
--- a/Detector/DetDriftChamber/compact/det.xml
+++ b/Detector/DetDriftChamber/compact/det.xml
@@ -65,8 +65,6 @@
     <constant name="DC_inner_chamber_enabled" value="1"/>
     <constant name="DC_outer_chamber_enabled" value="1"/>
 
-    <constant name="DC_safe_distance" value="0.02*mm"/>
-
   </define>
 
   <display>