diff --git a/control/json/utils/modifier.cpp b/control/json/utils/modifier.cpp
index 501a035..91978e7 100644
--- a/control/json/utils/modifier.cpp
+++ b/control/json/utils/modifier.cpp
@@ -93,7 +93,7 @@
  */
 struct MinusOperator : public Modifier::BaseOperator
 {
-    MinusOperator(const json& jsonObj) :
+    explicit MinusOperator(const json& jsonObj) :
         arg(ConfigBase::getJsonValue(jsonObj["value"]))
     {}
 
@@ -162,7 +162,7 @@
  */
 struct LessThanOperator : public Modifier::BaseOperator
 {
-    LessThanOperator(const json& jsonObj)
+    explicit LessThanOperator(const json& jsonObj)
     {
         const auto& valueArray = jsonObj["value"];
         if (!valueArray.is_array())
diff --git a/control/json/utils/modifier.hpp b/control/json/utils/modifier.hpp
index 8959203..92fdb70 100644
--- a/control/json/utils/modifier.hpp
+++ b/control/json/utils/modifier.hpp
@@ -80,7 +80,7 @@
      *
      * @param[in] jsonObj - The JSON config object
      */
-    Modifier(const json& jsonObj);
+    explicit Modifier(const json& jsonObj);
 
     /**
      * @brief Performs the operation
diff --git a/control/json/utils/pcie_card_metadata.hpp b/control/json/utils/pcie_card_metadata.hpp
index a879a51..c6b2083 100644
--- a/control/json/utils/pcie_card_metadata.hpp
+++ b/control/json/utils/pcie_card_metadata.hpp
@@ -68,7 +68,7 @@
      *
      * @param[in] systemNames - The system names values
      */
-    PCIeCardMetadata(const std::vector<std::string>& systemNames);
+    explicit PCIeCardMetadata(const std::vector<std::string>& systemNames);
 
     /**
      * @brief Look up a floor index based on a card's metadata