diff --git a/modules/reactor/src/meshgenerators/AssemblyMeshGenerator.C b/modules/reactor/src/meshgenerators/AssemblyMeshGenerator.C
index 42ed71ef94fd..274cef66dbea 100644
--- a/modules/reactor/src/meshgenerators/AssemblyMeshGenerator.C
+++ b/modules/reactor/src/meshgenerators/AssemblyMeshGenerator.C
@@ -322,7 +322,7 @@ AssemblyMeshGenerator::AssemblyMeshGenerator(const InputParameters & parameters)
       }
 
       params.set<boundary_id_type>("external_boundary_id") = _assembly_boundary_id;
-      params.set<std::string>("external_boundary_name") = _assembly_boundary_name;
+      params.set<BoundaryName>("external_boundary_name") = _assembly_boundary_name;
 
       addMeshSubgenerator(patterned_mg_name, name() + "_pattern", params);
 
@@ -528,9 +528,9 @@ AssemblyMeshGenerator::generateFlexibleAssemblyBoundaries()
     params.set<MooseEnum>("boundary_type") = (_geom_type == "Hex") ? "HEXAGON" : "CARTESIAN";
     params.set<unsigned int>("boundary_sectors") =
         getReactorParam<unsigned int>(RGMB::num_sectors_flexible_stitching);
-    params.set<double>("boundary_size") = getReactorParam<Real>(RGMB::assembly_pitch);
+    params.set<Real>("boundary_size") = getReactorParam<Real>(RGMB::assembly_pitch);
     params.set<boundary_id_type>("external_boundary_id") = _assembly_boundary_id;
-    params.set<std::string>("external_boundary_name") = _assembly_boundary_name;
+    params.set<BoundaryName>("external_boundary_name") = _assembly_boundary_name;
     params.set<SubdomainName>("background_subdomain_name") = block_to_delete + "_TRI";
     params.set<unsigned short>("background_subdomain_id") = 19999;
 
diff --git a/modules/reactor/src/meshgenerators/FlexiblePatternGenerator.C b/modules/reactor/src/meshgenerators/FlexiblePatternGenerator.C
index 79e8364ba259..db9969c6daf3 100644
--- a/modules/reactor/src/meshgenerators/FlexiblePatternGenerator.C
+++ b/modules/reactor/src/meshgenerators/FlexiblePatternGenerator.C
@@ -122,8 +122,9 @@ FlexiblePatternGenerator::validParams()
   params.addParam<boundary_id_type>(
       "external_boundary_id",
       "The boundary id of the external boundary in addition to the default 10000.");
-  params.addParam<std::string>(
-      "external_boundary_name", std::string(), "Optional boundary name for the external boundary.");
+  params.addParam<BoundaryName>("external_boundary_name",
+                                BoundaryName(),
+                                "Optional boundary name for the external boundary.");
 
   params.addParam<bool>("delete_default_external_boundary_from_inputs",
                         true,
diff --git a/modules/reactor/src/meshgenerators/PinMeshGenerator.C b/modules/reactor/src/meshgenerators/PinMeshGenerator.C
index 80bfc416b087..3b5b28e1b24a 100644
--- a/modules/reactor/src/meshgenerators/PinMeshGenerator.C
+++ b/modules/reactor/src/meshgenerators/PinMeshGenerator.C
@@ -214,7 +214,7 @@ PinMeshGenerator::PinMeshGenerator(const InputParameters & parameters)
       params.set<boundary_id_type>("external_boundary_id") = 20000 + _pin_type;
       const auto boundary_name = _is_assembly ? "outer_assembly_" + std::to_string(_pin_type)
                                               : "outer_pin_" + std::to_string(_pin_type);
-      params.set<std::string>("external_boundary_name") = boundary_name;
+      params.set<BoundaryName>("external_boundary_name") = boundary_name;
       params.set<std::vector<subdomain_id_type>>("block_id") = {_quad_center ? pin_block_id_start
                                                                              : pin_block_id_tri};
       params.set<MooseEnum>("element_type") = _quad_center ? "QUAD" : "TRI";
@@ -340,7 +340,7 @@ PinMeshGenerator::PinMeshGenerator(const InputParameters & parameters)
         params.set<boundary_id_type>("external_boundary_id") = 20000 + _pin_type;
         const auto boundary_name = _is_assembly ? "outer_assembly_" + std::to_string(_pin_type)
                                                 : "outer_pin_" + std::to_string(_pin_type);
-        params.set<std::string>("external_boundary_name") = boundary_name;
+        params.set<BoundaryName>("external_boundary_name") = boundary_name;
         bool flat_side_up = (_mesh_geometry == "Square");
         params.set<bool>("flat_side_up") = flat_side_up;
         params.set<bool>("create_outward_interface_boundaries") = false;
@@ -521,9 +521,9 @@ PinMeshGenerator::generateFlexibleAssemblyBoundaries()
     params.set<MooseEnum>("boundary_type") = (_mesh_geometry == "Hex") ? "HEXAGON" : "CARTESIAN";
     params.set<unsigned int>("boundary_sectors") =
         getReactorParam<unsigned int>(RGMB::num_sectors_flexible_stitching);
-    params.set<double>("boundary_size") = getReactorParam<Real>(RGMB::assembly_pitch);
+    params.set<Real>("boundary_size") = getReactorParam<Real>(RGMB::assembly_pitch);
     params.set<boundary_id_type>("external_boundary_id") = 20000 + _pin_type;
-    params.set<std::string>("external_boundary_name") =
+    params.set<BoundaryName>("external_boundary_name") =
         "outer_assembly_" + std::to_string(_pin_type);
     params.set<SubdomainName>("background_subdomain_name") = outermost_block_name + "_TRI";
     // Allocate block ID 9998 for triangulated outer region, since 9999 is reserved for tri elements