diff --git a/RecFCCeeCalorimeter/src/components/AugmentClustersFCCee.cpp b/RecFCCeeCalorimeter/src/components/AugmentClustersFCCee.cpp
index c30b0f0f..8cf0900c 100644
--- a/RecFCCeeCalorimeter/src/components/AugmentClustersFCCee.cpp
+++ b/RecFCCeeCalorimeter/src/components/AugmentClustersFCCee.cpp
@@ -633,16 +633,33 @@ StatusCode AugmentClustersFCCee::execute([[maybe_unused]] const EventContext &ev
 
         // do pi0/photon shape var only for EMB
         if (m_do_photon_shapeVar && systemID == systemID_EMB) {
-	  double w_theta;
           if (m_do_widthTheta_logE_weights) {
-            w_theta = (sumWeightLayer[layer+startPositionToFill] != 0.) ? sqrt(theta2_E_layer[layer+startPositionToFill] / sumWeightLayer[layer+startPositionToFill] - std::pow(theta_E_layer[layer+startPositionToFill] / sumWeightLayer[layer+startPositionToFill], 2)) : 0. ;
+            double w_theta2 = theta2_E_layer[layer+startPositionToFill] / sumWeightLayer[layer+startPositionToFill] - std::pow(theta_E_layer[layer+startPositionToFill] / sumWeightLayer[layer+startPositionToFill], 2);
+            // Very small but negative values caused by computational precision are allowed,
+            // otherwise crash.
+            if (w_theta2 < -1e-9) {
+              error() << "w_theta2 in theta width calculation is negative: " << w_theta2 << endmsg;
+              return StatusCode::FAILURE;
+            }
+            width_theta[layer+startPositionToFill] = (sumWeightLayer[layer+startPositionToFill] > 0.) ? std::sqrt(std::fabs(w_theta2)) : 0. ;
           } else {
-            w_theta = (sumEnLayer[layer+startPositionToFill] > 0.) ? sqrt(theta2_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill] - std::pow(theta_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill], 2)) : 0. ;
+            double w_theta2 = theta2_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill] - std::pow(theta_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill], 2);
+            // Very small but negative values caused by computational precision are allowed,
+            // otherwise crash.
+            if (w_theta2 < -1e-9) {
+              error() << "w_theta2 in theta width calculation is negative: " << w_theta2 << endmsg;
+              return StatusCode::FAILURE;
+            }
+            width_theta[layer+startPositionToFill] = (sumEnLayer[layer+startPositionToFill] > 0.) ? std::sqrt(std::fabs(w_theta2)) : 0. ;
 	  }
-	  width_theta[layer+startPositionToFill] = w_theta;
-
-          double w_module = (sumEnLayer[layer+startPositionToFill] > 0.) ? sqrt(module2_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill] - std::pow(module_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill], 2)) : 0. ;
-          width_module[layer+startPositionToFill] = w_module;
+          double w_module2 = module2_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill] - std::pow(module_E_layer[layer+startPositionToFill] / sumEnLayer[layer+startPositionToFill], 2);
+          // Very small but negative values caused by computational precision are allowed,
+          // otherwise crash.
+          if (w_module2 < -1e-9) {
+            error() << "w_module2 in module width calculation is negative: " << w_module2 << endmsg;
+            return StatusCode::FAILURE;
+          }
+          width_module[layer+startPositionToFill] = (sumEnLayer[layer+startPositionToFill] > 0.) ? std::sqrt(std::fabs(w_module2)) : 0. ;
 
           double Ratio_E = (E_cell_Max[layer+startPositionToFill] - E_cell_secMax[layer+startPositionToFill]) /
                            (E_cell_Max[layer+startPositionToFill] + E_cell_secMax[layer+startPositionToFill]);
@@ -766,15 +783,34 @@ StatusCode AugmentClustersFCCee::execute([[maybe_unused]] const EventContext &ev
               double theta2_E_9Bin = theta2_E_7Bin + theta_m4 * theta_m4 * weightLog_m4 + theta_p4 * theta_p4 * weightLog_p4;
               double theta_E_9Bin = theta_E_7Bin + theta_m4 * weightLog_m4 + theta_p4 * weightLog_p4;
 
-              double _w_theta_3Bin = sqrt(theta2_E_3Bin / sum_weightLog_3Bin - std::pow(theta_E_3Bin / sum_weightLog_3Bin, 2));
-              double _w_theta_5Bin = sqrt(theta2_E_5Bin / sum_weightLog_5Bin - std::pow(theta_E_5Bin / sum_weightLog_5Bin, 2));
-              double _w_theta_7Bin = sqrt(theta2_E_7Bin / sum_weightLog_7Bin - std::pow(theta_E_7Bin / sum_weightLog_7Bin, 2));
-              double _w_theta_9Bin = sqrt(theta2_E_9Bin / sum_weightLog_9Bin - std::pow(theta_E_9Bin / sum_weightLog_9Bin, 2));
-
-              width_theta_3Bin[layer+startPositionToFill] = (sum_weightLog_3Bin > 0.) ? _w_theta_3Bin : 0. ;
-              width_theta_5Bin[layer+startPositionToFill] = (sum_weightLog_5Bin > 0.) ? _w_theta_5Bin : 0. ;
-              width_theta_7Bin[layer+startPositionToFill] = (sum_weightLog_7Bin > 0.) ? _w_theta_7Bin : 0. ;
-              width_theta_9Bin[layer+startPositionToFill] = (sum_weightLog_9Bin > 0.) ? _w_theta_9Bin : 0. ;
+              double _w_theta_3Bin2 = theta2_E_3Bin / sum_weightLog_3Bin - std::pow(theta_E_3Bin / sum_weightLog_3Bin, 2);
+              double _w_theta_5Bin2 = theta2_E_5Bin / sum_weightLog_5Bin - std::pow(theta_E_5Bin / sum_weightLog_5Bin, 2);
+              double _w_theta_7Bin2 = theta2_E_7Bin / sum_weightLog_7Bin - std::pow(theta_E_7Bin / sum_weightLog_7Bin, 2);
+              double _w_theta_9Bin2 = theta2_E_9Bin / sum_weightLog_9Bin - std::pow(theta_E_9Bin / sum_weightLog_9Bin, 2);
+
+              // Very small but negative values caused by computational precision are allowed,
+              // otherwise crash.
+              if (_w_theta_3Bin2 < -1e-9) {
+                error() << "_w_theta_3Bin2 in theta width calculation is negative: " << _w_theta_3Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+              if (_w_theta_5Bin2 < -1e-9) {
+                error() << "_w_theta_5Bin2 in theta width calculation is negative: " << _w_theta_5Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+              if (_w_theta_7Bin2 < -1e-9) {
+                error() << "_w_theta_7Bin2 in theta width calculation is negative: " << _w_theta_7Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+              if (_w_theta_9Bin2 < -1e-9) {
+                error() << "_w_theta_9Bin2 in theta width calculation is negative: " << _w_theta_9Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+
+              width_theta_3Bin[layer+startPositionToFill] = (sum_weightLog_3Bin > 0.) ? std::sqrt(std::fabs(_w_theta_3Bin2)) : 0. ;
+              width_theta_5Bin[layer+startPositionToFill] = (sum_weightLog_5Bin > 0.) ? std::sqrt(std::fabs(_w_theta_5Bin2)) : 0. ;
+              width_theta_7Bin[layer+startPositionToFill] = (sum_weightLog_7Bin > 0.) ? std::sqrt(std::fabs(_w_theta_7Bin2)) : 0. ;
+              width_theta_9Bin[layer+startPositionToFill] = (sum_weightLog_9Bin > 0.) ? std::sqrt(std::fabs(_w_theta_9Bin2)) : 0. ;
             } else {
               double theta2_E_3Bin = theta_m1 * theta_m1 * E_m1 + E_cell_Max_theta[layer+startPositionToFill] * E_cell_Max_theta[layer+startPositionToFill] * E_cell_Max[layer+startPositionToFill] + theta_p1 * theta_p1 * E_p1;
               double theta_E_3Bin = theta_m1 * E_m1 + E_cell_Max_theta[layer+startPositionToFill] * E_cell_Max[layer+startPositionToFill] + theta_p1 * E_p1;
@@ -785,15 +821,34 @@ StatusCode AugmentClustersFCCee::execute([[maybe_unused]] const EventContext &ev
               double theta2_E_9Bin = theta2_E_7Bin + theta_m4 * theta_m4 * E_m4 + theta_p4 * theta_p4 * E_p4;
               double theta_E_9Bin = theta_E_7Bin + theta_m4 * E_m4 + theta_p4 * E_p4;
 
-              double _w_theta_3Bin = sqrt(theta2_E_3Bin / sum_E_3Bin - std::pow(theta_E_3Bin / sum_E_3Bin, 2));
-              double _w_theta_5Bin = sqrt(theta2_E_5Bin / sum_E_5Bin - std::pow(theta_E_5Bin / sum_E_5Bin, 2));
-              double _w_theta_7Bin = sqrt(theta2_E_7Bin / sum_E_7Bin - std::pow(theta_E_7Bin / sum_E_7Bin, 2));
-              double _w_theta_9Bin = sqrt(theta2_E_9Bin / sum_E_9Bin - std::pow(theta_E_9Bin / sum_E_9Bin, 2));
-
-              width_theta_3Bin[layer+startPositionToFill] = (sum_E_3Bin > 0.) ? _w_theta_3Bin : 0. ;
-              width_theta_5Bin[layer+startPositionToFill] = (sum_E_5Bin > 0.) ? _w_theta_5Bin : 0. ;
-              width_theta_7Bin[layer+startPositionToFill] = (sum_E_7Bin > 0.) ? _w_theta_7Bin : 0. ;
-              width_theta_9Bin[layer+startPositionToFill] = (sum_E_9Bin > 0.) ? _w_theta_9Bin : 0. ;
+              double _w_theta_3Bin2 = theta2_E_3Bin / sum_E_3Bin - std::pow(theta_E_3Bin / sum_E_3Bin, 2);
+              double _w_theta_5Bin2 = theta2_E_5Bin / sum_E_5Bin - std::pow(theta_E_5Bin / sum_E_5Bin, 2);
+              double _w_theta_7Bin2 = theta2_E_7Bin / sum_E_7Bin - std::pow(theta_E_7Bin / sum_E_7Bin, 2);
+              double _w_theta_9Bin2 = theta2_E_9Bin / sum_E_9Bin - std::pow(theta_E_9Bin / sum_E_9Bin, 2);
+
+              // Very small but negative values caused by computational precision are allowed,
+              // otherwise crash.
+              if (_w_theta_3Bin2 < -1e-9) {
+                error() << "_w_theta_3Bin2 in theta width calculation is negative: " << _w_theta_3Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+              if (_w_theta_5Bin2 < -1e-9) {
+                error() << "_w_theta_5Bin2 in theta width calculation is negative: " << _w_theta_5Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+              if (_w_theta_7Bin2 < -1e-9) {
+                error() << "_w_theta_7Bin2 in theta width calculation is negative: " << _w_theta_7Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+              if (_w_theta_9Bin2 < -1e-9) {
+                error() << "_w_theta_9Bin2 in theta width calculation is negative: " << _w_theta_9Bin2 << endmsg;
+                return StatusCode::FAILURE;
+              }
+
+              width_theta_3Bin[layer+startPositionToFill] = (sum_E_3Bin > 0.) ? std::sqrt(std::fabs(_w_theta_3Bin2)) : 0. ;
+              width_theta_5Bin[layer+startPositionToFill] = (sum_E_5Bin > 0.) ? std::sqrt(std::fabs(_w_theta_5Bin2)) : 0. ;
+              width_theta_7Bin[layer+startPositionToFill] = (sum_E_7Bin > 0.) ? std::sqrt(std::fabs(_w_theta_7Bin2)) : 0. ;
+              width_theta_9Bin[layer+startPositionToFill] = (sum_E_9Bin > 0.) ? std::sqrt(std::fabs(_w_theta_9Bin2)) : 0. ;
             }
             E_fr_side_pm2[layer+startPositionToFill] = (sum_E_3Bin > 0.) ? (sum_E_5Bin / sum_E_3Bin - 1.) : 0. ;
             E_fr_side_pm3[layer+startPositionToFill] = (sum_E_3Bin > 0.) ? (sum_E_7Bin / sum_E_3Bin - 1.) : 0. ;