diff --git a/src/DIELECTRIC/fix_polarize_bem_gmres.cpp b/src/DIELECTRIC/fix_polarize_bem_gmres.cpp
index b3de7d78c0..62fa7e8641 100644
--- a/src/DIELECTRIC/fix_polarize_bem_gmres.cpp
+++ b/src/DIELECTRIC/fix_polarize_bem_gmres.cpp
@@ -287,8 +287,10 @@ void FixPolarizeBEMGMRES::setup(int /*vflag*/)
   //             = 0.000240258
 
   epsilon0e2q = 1.0;
-  if (strcmp(update->unit_style,"real") == 0)
+  if (strcmp(update->unit_style, "real") == 0)
     epsilon0e2q = 0.0795776 / force->qqrd2e;
+  else if (strcmp(update->unit_style, "lj") != 0)
+    error->all(FLERR, "Only unit styles 'real' and 'lj' are supported");
 
   first = 1;
   compute_induced_charges();
diff --git a/src/DIELECTRIC/fix_polarize_bem_icc.cpp b/src/DIELECTRIC/fix_polarize_bem_icc.cpp
index d49e84d4a5..8cd0fb4332 100644
--- a/src/DIELECTRIC/fix_polarize_bem_icc.cpp
+++ b/src/DIELECTRIC/fix_polarize_bem_icc.cpp
@@ -193,8 +193,10 @@ void FixPolarizeBEMICC::setup(int /*vflag*/)
   //             = 0.000240258
 
   epsilon0e2q = 1.0;
-  if (strcmp(update->unit_style,"real") == 0)
+  if (strcmp(update->unit_style, "real") == 0)
     epsilon0e2q = 0.0795776 / force->qqrd2e;
+  else if (strcmp(update->unit_style, "lj") != 0)
+    error->all(FLERR, "Only unit styles 'lj' and 'real' are supported");
 
   compute_induced_charges();
 }