diff --git a/macro/mcbm/geometry/rich/create_rich_v21a_mcbm.C b/macro/mcbm/geometry/rich/create_rich_v21a_mcbm.C
index 7dfa604bd5d790be5df3a4d34e046e4cf7cfb148..0322c46e66162ee3564dbd94ac646f4d001e9d17 100644
--- a/macro/mcbm/geometry/rich/create_rich_v21a_mcbm.C
+++ b/macro/mcbm/geometry/rich/create_rich_v21a_mcbm.C
@@ -2,6 +2,8 @@
    SPDX-License-Identifier: GPL-3.0-only
    Authors: Florian Uhlig [committer] */
 
+// clang-format off
+
 #include <iostream>
 //#include "FairGeoMedium.h"
 //#include "FairGeoBuilder.h"
@@ -29,6 +31,9 @@ void create_rich_v21a_mcbm()
 {
   gSystem->Load("libGeom");
 
+  // Load FairRunSim to ensure the correct unit system
+  FairRunSim* sim = new FairRunSim();
+
   TString geoFileName = "rich_v21a_mcbm.geo.root";
   TString topNodeName = "rich_v21a_mcbm";
 
diff --git a/macro/mcbm/geometry/rich/create_rich_v21b_mcbm.C b/macro/mcbm/geometry/rich/create_rich_v21b_mcbm.C
index 6b901a30dafe4d570eaae3008018f68521540ca2..fbfa1229e19d3e548d04308825b443676e9af22c 100644
--- a/macro/mcbm/geometry/rich/create_rich_v21b_mcbm.C
+++ b/macro/mcbm/geometry/rich/create_rich_v21b_mcbm.C
@@ -15,7 +15,7 @@ using namespace std;
 
 // Changelog
 
-// 2022-03-08 - v21b - DE - Based on v21a, relocate RICH along the rail onto the 25 degree line
+// 2022-03-08 - v21b - DE - Based on v21a, relocate RICH along the rail onto the 25 degree line by -20 cm
 // 2021-09-28 - v21a - SR - Based on v20d, moved RICH according to the TOF v21d
 // 2020-05-25 - v20d - AW - Move mRICH by +7.2cm in Z accordingly to the mTOF movement from rev 16441
 // 2020-05-20 - v20d - AW - changed positioning to +2.5cm to 25°line (nearer to beam axis) (from Analysis)
@@ -32,6 +32,9 @@ void create_rich_v21b_mcbm()
 {
   gSystem->Load("libGeom");
 
+  // Load FairRunSim to ensure the correct unit system
+  FairRunSim* sim = new FairRunSim();
+
   TString geoFileName = "rich_v21b_mcbm.geo.root";
   TString topNodeName = "rich_v21b_mcbm";