diff --git a/Core/src/Detector/GlueVolumesDescriptor.cpp b/Core/src/Detector/GlueVolumesDescriptor.cpp
index def0b1fcb40649d5cc1f633fa791b4874799c472..886c4a3acd96b381a3d26e777aad554ca87ba9cf 100644
--- a/Core/src/Detector/GlueVolumesDescriptor.cpp
+++ b/Core/src/Detector/GlueVolumesDescriptor.cpp
@@ -20,7 +20,7 @@ void Acts::GlueVolumesDescriptor::registerGlueVolumes(Acts::BoundarySurfaceFace
   auto searchIter= m_glueVolumes.find(bsf);
    if (searchIter == m_glueVolumes.end()) m_glueFaces.push_back(bsf);
   // simple assignment overwrites already existing entries
-  m_glueVolumes.at(bsf) = gvs;   //!< @todo change to addGlueVolumes principle
+  m_glueVolumes[bsf] = gvs;   //!< @todo change to addGlueVolumes principle
 
 }
 
diff --git a/Core/src/Detector/TrackingGeometry.cpp b/Core/src/Detector/TrackingGeometry.cpp
index 36f04e103e067c600c889b0634372c0e9d88e664..184ff6f45192e802b9da075e424143d1e1ee909b 100644
--- a/Core/src/Detector/TrackingGeometry.cpp
+++ b/Core/src/Detector/TrackingGeometry.cpp
@@ -60,7 +60,7 @@ void Acts::TrackingGeometry::registerTrackingVolumes(const Acts::TrackingVolume&
 
     tvol.setMotherVolume(mvol);
     
-    m_trackingVolumes.at(tvol.volumeName()) = (&tvol);
+    m_trackingVolumes[tvol.volumeName()] = (&tvol);
     std::shared_ptr<const Acts::TrackingVolumeArray> confinedVolumes = tvol.confinedVolumes();
     if (confinedVolumes){
         for (auto& volumesIter: confinedVolumes->arrayObjects())