diff --git a/opm/models/io/baseoutputmodule.hh b/opm/models/io/baseoutputmodule.hh
index 36bc78b32..81ca8fe2e 100644
--- a/opm/models/io/baseoutputmodule.hh
+++ b/opm/models/io/baseoutputmodule.hh
@@ -38,10 +38,11 @@
 #include <dune/istl/bvector.hh>
 #include <dune/common/fvector.hh>
 
-#include <vector>
+#include <array>
 #include <sstream>
 #include <string>
-#include <array>
+#include <string_view>
+#include <vector>
 
 #include <cstdio>
 
@@ -422,7 +423,7 @@ protected:
     {
         char name[512];
         for (unsigned i = 0; i < numPhases; ++i) {
-            snprintf(name, 512, pattern, FluidSystem::phaseName(i));
+            snprintf(name, 512, pattern, FluidSystem::phaseName(i).data());
 
             if (bufferType == DofBuffer)
                 DiscBaseOutputModule::attachScalarDofData_(baseWriter, buffer[i], name);
@@ -445,7 +446,7 @@ protected:
     {
         char name[512];
         for (unsigned i = 0; i < numComponents; ++i) {
-            snprintf(name, 512, pattern, FluidSystem::componentName(i));
+            snprintf(name, 512, pattern, FluidSystem::componentName(i).data());
 
             if (bufferType == DofBuffer)
                 DiscBaseOutputModule::attachScalarDofData_(baseWriter, buffer[i], name);
@@ -470,8 +471,8 @@ protected:
         for (unsigned i= 0; i < numPhases; ++i) {
             for (unsigned j = 0; j < numComponents; ++j) {
                 snprintf(name, 512, pattern,
-                         FluidSystem::phaseName(i),
-                         FluidSystem::componentName(j));
+                         FluidSystem::phaseName(i).data(),
+                         FluidSystem::componentName(j).data());
 
                 if (bufferType == DofBuffer)
                     DiscBaseOutputModule::attachScalarDofData_(baseWriter, buffer[i][j], name);
diff --git a/opm/models/io/vtkdiscretefracturemodule.hh b/opm/models/io/vtkdiscretefracturemodule.hh
index f0b771513..7496d33e0 100644
--- a/opm/models/io/vtkdiscretefracturemodule.hh
+++ b/opm/models/io/vtkdiscretefracturemodule.hh
@@ -38,6 +38,7 @@
 #include <dune/common/fvector.hh>
 
 #include <cstdio>
+#include <string_view>
 
 namespace Opm::Properties {
 
@@ -308,7 +309,7 @@ public:
                         std::max<Scalar>(1e-20, fractureVelocityWeight_[phaseIdx][dofIdx]);
                 // commit the phase velocity
                 char name[512];
-                snprintf(name, 512, "fractureFilterVelocity_%s", FluidSystem::phaseName(phaseIdx));
+                snprintf(name, 512, "fractureFilterVelocity_%s", FluidSystem::phaseName(phaseIdx).data());
 
                 DiscBaseOutputModule::attachVectorDofData_(baseWriter, fractureVelocity_[phaseIdx], name);
             }
diff --git a/opm/models/io/vtkmultiphasemodule.hh b/opm/models/io/vtkmultiphasemodule.hh
index 33ff5a209..13664f10a 100644
--- a/opm/models/io/vtkmultiphasemodule.hh
+++ b/opm/models/io/vtkmultiphasemodule.hh
@@ -39,6 +39,7 @@
 #include <dune/common/fvector.hh>
 
 #include <cstdio>
+#include <string_view>
 
 namespace Opm::Properties {
 
@@ -376,7 +377,7 @@ public:
                     velocity_[phaseIdx][i] /= velocityWeight_[phaseIdx][i];
                 // commit the phase velocity
                 char name[512];
-                snprintf(name, 512, "filterVelocity_%s", FluidSystem::phaseName(phaseIdx));
+                snprintf(name, 512, "filterVelocity_%s", FluidSystem::phaseName(phaseIdx).data());
 
                 DiscBaseOutputModule::attachVectorDofData_(baseWriter, velocity_[phaseIdx], name);
             }
@@ -392,7 +393,7 @@ public:
                     potentialGradient_[phaseIdx][i] /= potentialWeight_[phaseIdx][i];
                 // commit the phase velocity
                 char name[512];
-                snprintf(name, 512, "gradP_%s", FluidSystem::phaseName(phaseIdx));
+                snprintf(name, 512, "gradP_%s", FluidSystem::phaseName(phaseIdx).data());
 
                 DiscBaseOutputModule::attachVectorDofData_(baseWriter,
                                                            potentialGradient_[phaseIdx],