diff --git a/examples/tv-app/android/include/account-login/AccountLoginManager.cpp b/examples/tv-app/android/include/account-login/AccountLoginManager.cpp
index 73ebb9fc8e5723..0d791265873c29 100644
--- a/examples/tv-app/android/include/account-login/AccountLoginManager.cpp
+++ b/examples/tv-app/android/include/account-login/AccountLoginManager.cpp
@@ -35,7 +35,7 @@ const auto loginSetupPINFieldId = std::to_string(chip::to_underlying(AccountLogi
 const auto loginNodeFieldId     = std::to_string(chip::to_underlying(AccountLogin::Commands::Login::Fields::kNode));
 const auto logoutNodeFieldId    = std::to_string(chip::to_underlying(AccountLogin::Commands::Logout::Fields::kNode));
 
-string charSpanToString(const CharSpan & charSpan)
+std::string charSpanToString(const CharSpan & charSpan)
 {
     return { charSpan.data(), charSpan.size() };
 }
@@ -127,10 +127,10 @@ bool AccountLoginManager::HandleLogout(const chip::Optional<chip::NodeId> & node
 void AccountLoginManager::HandleGetSetupPin(CommandResponseHelper<GetSetupPINResponse> & helper,
                                             const CharSpan & tempAccountIdentifier)
 {
-    string tempAccountIdentifierString(tempAccountIdentifier.data(), tempAccountIdentifier.size());
+    std::string tempAccountIdentifierString(tempAccountIdentifier.data(), tempAccountIdentifier.size());
 
     GetSetupPINResponse response;
-    ChipLogProgress(Zcl, "temporary account id: %s returning pin: %s", tempAccountIdentifierString.c_str(), mSetupPin);
+    ChipLogProgress(Zcl, "temporary account id: %s returning pin: %s", tempAccountIdentifierString.std::c_str(), mSetupPin);
 
     response.setupPIN = CharSpan::fromCharString(mSetupPin);
     helper.Success(response);
@@ -143,7 +143,7 @@ void AccountLoginManager::GetSetupPin(char * setupPin, size_t setupPinSize, cons
     // Other methods in this class do not need to be changed beecause those will get routed to java layer
     // upstream.
     ChipLogProgress(DeviceLayer, "AccountLoginManager::GetSetupPin called for endpoint %d", mEndpointId);
-    string tempAccountIdentifierString(tempAccountIdentifier.data(), tempAccountIdentifier.size());
+    std::string tempAccountIdentifierString(tempAccountIdentifier.data(), tempAccountIdentifier.size());
     if (mCommandDelegate == nullptr)
     {
         // For the dummy content apps to work.
diff --git a/examples/tv-app/android/include/content-launcher/AppContentLauncherManager.cpp b/examples/tv-app/android/include/content-launcher/AppContentLauncherManager.cpp
index d4bb85088e6abd..f10cb35990c4e8 100644
--- a/examples/tv-app/android/include/content-launcher/AppContentLauncherManager.cpp
+++ b/examples/tv-app/android/include/content-launcher/AppContentLauncherManager.cpp
@@ -31,7 +31,7 @@ using namespace chip::app::Clusters::ContentLauncher;
 using ContentAppAttributeDelegate = chip::AppPlatform::ContentAppAttributeDelegate;
 
 AppContentLauncherManager::AppContentLauncherManager(ContentAppAttributeDelegate * attributeDelegate,
-                                                     list<std::string> acceptHeaderList, uint32_t supportedStreamingProtocols) :
+                                                     std::list<std::string> acceptHeaderList, uint32_t supportedStreamingProtocols) :
     mAttributeDelegate(attributeDelegate)
 {
     mAcceptHeaderList            = acceptHeaderList;
@@ -45,7 +45,7 @@ void AppContentLauncherManager::HandleLaunchContent(CommandResponseHelper<Launch
                                                     bool useCurrentContext)
 {
     ChipLogProgress(Zcl, "AppContentLauncherManager::HandleLaunchContent for endpoint %d", mEndpointId);
-    string dataString(data.data(), data.size());
+    std::string dataString(data.data(), data.size());
 
     ChipLogProgress(Zcl, " AutoPlay=%s", (autoplay ? "true" : "false"));
 
@@ -75,8 +75,8 @@ void AppContentLauncherManager::HandleLaunchUrl(CommandResponseHelper<LaunchResp
 {
     ChipLogProgress(Zcl, "AppContentLauncherManager::HandleLaunchUrl");
 
-    string contentUrlString(contentUrl.data(), contentUrl.size());
-    string displayStringString(displayString.data(), displayString.size());
+    std::string contentUrlString(contentUrl.data(), contentUrl.size());
+    std::string displayStringString(displayString.data(), displayString.size());
 
     // TODO: Insert code here
     LaunchResponseType response;
@@ -91,7 +91,7 @@ CHIP_ERROR AppContentLauncherManager::HandleGetAcceptHeaderList(AttributeValueEn
     chip::app::ConcreteReadAttributePath aPath(mEndpointId, chip::app::Clusters::ContentLauncher::Id,
                                                chip::app::Clusters::ContentLauncher::Attributes::AcceptHeader::Id);
     std::string resStr = mAttributeDelegate->Read(aPath);
-    ChipLogProgress(Zcl, "AppContentLauncherManager::HandleGetAcceptHeaderList response %s", resStr.c_str());
+    ChipLogProgress(Zcl, "AppContentLauncherManager::HandleGetAcceptHeaderList response %s", resStr.std::c_str());
 
     if (resStr.length() != 0)
     {
@@ -101,7 +101,7 @@ CHIP_ERROR AppContentLauncherManager::HandleGetAcceptHeaderList(AttributeValueEn
         {
             std::string attrId = std::to_string(chip::app::Clusters::ContentLauncher::Attributes::AcceptHeader::Id);
             ChipLogProgress(Zcl, "AppContentLauncherManager::HandleGetAcceptHeaderList response parsing done. reading attr %s",
-                            attrId.c_str());
+                            attrId.std::c_str());
             if (value[attrId].isArray())
             {
                 mAcceptHeaderList.clear();
@@ -132,7 +132,7 @@ uint32_t AppContentLauncherManager::HandleGetSupportedStreamingProtocols()
     chip::app::ConcreteReadAttributePath aPath(mEndpointId, chip::app::Clusters::ContentLauncher::Id,
                                                chip::app::Clusters::ContentLauncher::Attributes::SupportedStreamingProtocols::Id);
     std::string resStr = mAttributeDelegate->Read(aPath);
-    ChipLogProgress(Zcl, "AppContentLauncherManager::HandleGetSupportedStreamingProtocols response %s", resStr.c_str());
+    ChipLogProgress(Zcl, "AppContentLauncherManager::HandleGetSupportedStreamingProtocols response %s", resStr.std::c_str());
 
     if (resStr.length() == 0)
     {
@@ -147,7 +147,7 @@ uint32_t AppContentLauncherManager::HandleGetSupportedStreamingProtocols()
     }
     std::string attrId = std::to_string(chip::app::Clusters::ContentLauncher::Attributes::SupportedStreamingProtocols::Id);
     ChipLogProgress(Zcl, "AppContentLauncherManager::HandleGetSupportedStreamingProtocols response parsing done. reading attr %s",
-                    attrId.c_str());
+                    attrId.std::c_str());
     if (!value[attrId].empty() && value[attrId].isInt())
     {
         uint32_t supportedStreamingProtocols = static_cast<uint32_t>(value[attrId].asInt());
diff --git a/examples/tv-app/android/include/media-playback/AppMediaPlaybackManager.cpp b/examples/tv-app/android/include/media-playback/AppMediaPlaybackManager.cpp
index e58d6eebb52462..2cac80594bf101 100644
--- a/examples/tv-app/android/include/media-playback/AppMediaPlaybackManager.cpp
+++ b/examples/tv-app/android/include/media-playback/AppMediaPlaybackManager.cpp
@@ -194,7 +194,7 @@ uint64_t AppMediaPlaybackManager::HandleMediaRequestGetAttribute(chip::Attribute
     ChipLogProgress(Zcl, "Received AppMediaPlaybackManager::HandleMediaRequestGetAttribute:%d", attributeId);
     chip::app::ConcreteReadAttributePath aPath(mEndpointId, chip::app::Clusters::MediaPlayback::Id, attributeId);
     std::string resStr = mAttributeDelegate->Read(aPath);
-    ChipLogProgress(Zcl, "AppMediaPlaybackManager::HandleMediaRequestGetAttribute response %s", resStr.c_str());
+    ChipLogProgress(Zcl, "AppMediaPlaybackManager::HandleMediaRequestGetAttribute response %s", resStr.std::c_str());
 
     uint64_t ret = std::numeric_limits<uint64_t>::max();
     if (resStr.length() != 0)
@@ -205,7 +205,7 @@ uint64_t AppMediaPlaybackManager::HandleMediaRequestGetAttribute(chip::Attribute
         {
             std::string attrId = std::to_string(attributeId);
             ChipLogProgress(Zcl, "AppMediaPlaybackManager::HandleMediaRequestGetAttribute response parsing done. reading attr %s",
-                            attrId.c_str());
+                            attrId.std::c_str());
             if (!value[attrId].empty() && value[attrId].isUInt())
             {
                 ret = static_cast<uint64_t>(value[attrId].asUInt());
@@ -241,7 +241,7 @@ CHIP_ERROR AppMediaPlaybackManager::HandleGetSampledPosition(AttributeValueEncod
     chip::app::ConcreteReadAttributePath aPath(mEndpointId, chip::app::Clusters::MediaPlayback::Id,
                                                chip::app::Clusters::MediaPlayback::Attributes::SampledPosition::Id);
     std::string resStr = mAttributeDelegate->Read(aPath);
-    ChipLogProgress(Zcl, "AppMediaPlaybackManager::HandleGetSampledPosition response %s", resStr.c_str());
+    ChipLogProgress(Zcl, "AppMediaPlaybackManager::HandleGetSampledPosition response %s", resStr.std::c_str());
 
     if (resStr.length() != 0)
     {
@@ -251,7 +251,7 @@ CHIP_ERROR AppMediaPlaybackManager::HandleGetSampledPosition(AttributeValueEncod
         {
             std::string attrId = std::to_string(chip::app::Clusters::MediaPlayback::Attributes::SampledPosition::Id);
             ChipLogProgress(Zcl, "AppContentLauncherManager::HandleGetSampledPosition response parsing done. reading attr %s",
-                            attrId.c_str());
+                            attrId.std::c_str());
             if (!value[attrId].empty() && value[attrId].isObject())
             {
                 std::string updatedAt = std::to_string(
diff --git a/examples/tv-app/android/include/target-navigator/TargetNavigatorManager.cpp b/examples/tv-app/android/include/target-navigator/TargetNavigatorManager.cpp
index 3b84a050d3e51a..20d1b3aca1ab7c 100644
--- a/examples/tv-app/android/include/target-navigator/TargetNavigatorManager.cpp
+++ b/examples/tv-app/android/include/target-navigator/TargetNavigatorManager.cpp
@@ -54,7 +54,7 @@ CHIP_ERROR TargetNavigatorManager::HandleGetTargetList(AttributeValueEncoder & a
             {
                 std::string attrId = std::to_string(chip::app::Clusters::TargetNavigator::Attributes::TargetList::Id);
                 ChipLogProgress(Zcl, "TargetNavigatorManager::HandleNavigateTarget response parsing done. reading attr %s",
-                                attrId.c_str());
+                                attrId.std::c_str());
                 if (value[attrId].isArray())
                 {
                     return aEncoder.EncodeList([&](const auto & encoder) -> CHIP_ERROR {
@@ -109,7 +109,7 @@ uint8_t TargetNavigatorManager::HandleGetCurrentTarget()
         chip::app::ConcreteReadAttributePath aPath(mEndpointId, chip::app::Clusters::TargetNavigator::Id,
                                                    chip::app::Clusters::TargetNavigator::Attributes::TargetList::Id);
         std::string resStr = mAttributeDelegate->Read(aPath);
-        ChipLogProgress(Zcl, "TargetNavigatorManager::HandleGetCurrentTarget response %s", resStr.c_str());
+        ChipLogProgress(Zcl, "TargetNavigatorManager::HandleGetCurrentTarget response %s", resStr.std::c_str());
 
         if (resStr.length() != 0)
         {
@@ -119,7 +119,7 @@ uint8_t TargetNavigatorManager::HandleGetCurrentTarget()
             {
                 std::string attrId = std::to_string(chip::app::Clusters::TargetNavigator::Attributes::CurrentTarget::Id);
                 ChipLogProgress(Zcl, "TargetNavigatorManager::HandleGetCurrentTarget response parsing done. reading attr %s",
-                                attrId.c_str());
+                                attrId.std::c_str());
                 if (value[attrId].isUInt() && value[attrId].asUInt() < 256)
                 {
                     return static_cast<uint8_t>(value[attrId].asUInt());
diff --git a/examples/tv-app/tv-common/clusters/media-input/MediaInputManager.cpp b/examples/tv-app/tv-common/clusters/media-input/MediaInputManager.cpp
index bd5582efcf0c27..7c0dc950de1f4f 100644
--- a/examples/tv-app/tv-common/clusters/media-input/MediaInputManager.cpp
+++ b/examples/tv-app/tv-common/clusters/media-input/MediaInputManager.cpp
@@ -19,7 +19,6 @@
 
 #include <string>
 
-using namespace std;
 using namespace chip;
 using namespace chip::app::Clusters::MediaInput;
 
@@ -76,11 +75,11 @@ bool MediaInputManager::HandleShowInputStatus()
     ChipLogProgress(Zcl, " MediaInputManager::HandleShowInputStatus()");
     for (auto const & inputInfo : this->mInputs)
     {
-        string name(inputInfo.name.data(), inputInfo.name.size());
-        string desc(inputInfo.description.data(), inputInfo.description.size());
+        std::string name(inputInfo.name.data(), inputInfo.name.size());
+        std::string desc(inputInfo.description.data(), inputInfo.description.size());
         ChipLogProgress(Zcl, " [%d] type=%d selected=%d name=%s desc=%s", inputInfo.index,
                         static_cast<uint16_t>(inputInfo.inputType), (mCurrentInput == inputInfo.index ? 1 : 0), name.c_str(),
-                        desc.c_str());
+                        desc.std::c_str());
     }
     return true;
 }
diff --git a/examples/tv-app/tv-common/clusters/media-playback/MediaPlaybackManager.cpp b/examples/tv-app/tv-common/clusters/media-playback/MediaPlaybackManager.cpp
index 0e79c6b2a3e9a3..91159021842e75 100644
--- a/examples/tv-app/tv-common/clusters/media-playback/MediaPlaybackManager.cpp
+++ b/examples/tv-app/tv-common/clusters/media-playback/MediaPlaybackManager.cpp
@@ -21,7 +21,6 @@
 
 #include <string>
 
-using namespace std;
 using namespace chip::app::DataModel;
 using namespace chip::app::Clusters::MediaPlayback;
 using namespace chip::Uint8;
diff --git a/examples/tv-app/tv-common/clusters/messages/MessagesManager.cpp b/examples/tv-app/tv-common/clusters/messages/MessagesManager.cpp
index 681cd56d6647fa..e0fbddbc170f9a 100644
--- a/examples/tv-app/tv-common/clusters/messages/MessagesManager.cpp
+++ b/examples/tv-app/tv-common/clusters/messages/MessagesManager.cpp
@@ -21,7 +21,6 @@
 #include <string>
 #include <vector>
 
-using namespace std;
 using namespace chip;
 using namespace chip::app;
 using namespace chip::app::Clusters::Messages;
@@ -34,7 +33,7 @@ CHIP_ERROR MessagesManager::HandlePresentMessagesRequest(
     const DataModel::Nullable<uint32_t> & startTime, const DataModel::Nullable<uint64_t> & duration, const CharSpan & messageText,
     const Optional<DataModel::DecodableList<MessageResponseOption>> & responses)
 {
-    ChipLogProgress(Zcl, "HandlePresentMessagesRequest message:%s", std::string(messageText.data(), messageText.size()).c_str());
+    ChipLogProgress(Zcl, "HandlePresentMessagesRequest message:%s", std::string(messageText.data(), messageText.size()).std::c_str());
 
     auto cachedMessage = CachedMessage(messageId, priority, messageControl, startTime, duration,
                                        std::string(messageText.data(), messageText.size()));
diff --git a/examples/tv-app/tv-common/clusters/target-navigator/TargetNavigatorManager.cpp b/examples/tv-app/tv-common/clusters/target-navigator/TargetNavigatorManager.cpp
index dced0371fb9f39..03932528e57b0d 100644
--- a/examples/tv-app/tv-common/clusters/target-navigator/TargetNavigatorManager.cpp
+++ b/examples/tv-app/tv-common/clusters/target-navigator/TargetNavigatorManager.cpp
@@ -21,7 +21,6 @@
 
 #include <string>
 
-using namespace std;
 using namespace chip::app;
 using namespace chip::app::Clusters::TargetNavigator;
 
diff --git a/examples/tv-casting-app/tv-casting-common/clusters/content-app-observer/ContentAppObserver.cpp b/examples/tv-casting-app/tv-casting-common/clusters/content-app-observer/ContentAppObserver.cpp
index a6010a54b0a0f5..8717354f22ff59 100644
--- a/examples/tv-casting-app/tv-casting-common/clusters/content-app-observer/ContentAppObserver.cpp
+++ b/examples/tv-casting-app/tv-casting-common/clusters/content-app-observer/ContentAppObserver.cpp
@@ -20,7 +20,6 @@
 #include <app-common/zap-generated/attributes/Accessors.h>
 #include <app/util/config.h>
 
-using namespace std;
 using namespace chip;
 using namespace chip::app::Clusters::ContentAppObserver;
 
@@ -35,11 +34,11 @@ void ContentAppObserverManager::HandleContentAppMessage(chip::app::CommandRespon
 {
     ChipLogProgress(Zcl, "ContentAppObserverManager::HandleContentAppMessage");
 
-    string dataString(data.HasValue() ? data.Value().data() : "", data.HasValue() ? data.Value().size() : 0);
-    string encodingHintString(encodingHint.data(), encodingHint.size());
+    std::string dataString(data.HasValue() ? data.Value().data() : "", data.HasValue() ? data.Value().size() : 0);
+    std::string encodingHintString(encodingHint.data(), encodingHint.size());
 
     ChipLogProgress(Zcl, "ContentAppObserverManager::HandleContentAppMessage TEST CASE hint=%s data=%s ",
-                    encodingHintString.c_str(), dataString.c_str());
+                    encodingHintString.std::c_str(), dataString.std::c_str());
 
     ContentAppMessageResponse response;
     // TODO: Insert code here
diff --git a/examples/tv-casting-app/tv-casting-common/core/CastingPlayerDiscovery.cpp b/examples/tv-casting-app/tv-casting-common/core/CastingPlayerDiscovery.cpp
index 81d1f78fe1b33a..4dee3550f3e0bb 100644
--- a/examples/tv-casting-app/tv-casting-common/core/CastingPlayerDiscovery.cpp
+++ b/examples/tv-casting-app/tv-casting-common/core/CastingPlayerDiscovery.cpp
@@ -25,7 +25,6 @@ namespace core {
 using namespace chip::System;
 using namespace chip::Controller;
 using namespace chip::Dnssd;
-using namespace std;
 
 CastingPlayerDiscovery * CastingPlayerDiscovery::_castingPlayerDiscovery = nullptr;
 
diff --git a/src/app/clusters/resource-monitoring-server/resource-monitoring-server.cpp b/src/app/clusters/resource-monitoring-server/resource-monitoring-server.cpp
index 4447ad1cc0f210..6c581ff72a9e19 100644
--- a/src/app/clusters/resource-monitoring-server/resource-monitoring-server.cpp
+++ b/src/app/clusters/resource-monitoring-server/resource-monitoring-server.cpp
@@ -34,7 +34,6 @@
 #include <lib/support/TypeTraits.h>
 #include <protocols/interaction_model/StatusCode.h>
 
-// using namespace std;
 using namespace chip::app;
 using namespace chip::app::Clusters;
 using namespace chip::app::Clusters::ResourceMonitoring;
diff --git a/src/lib/support/SafeInt.h b/src/lib/support/SafeInt.h
index ecf6d8721dcb1d..2835ef05534155 100644
--- a/src/lib/support/SafeInt.h
+++ b/src/lib/support/SafeInt.h
@@ -37,11 +37,10 @@ namespace chip {
 template <typename T, typename U, std::enable_if_t<std::is_integral<T>::value, int> = 0>
 bool CanCastTo(U arg)
 {
-    using namespace std;
     // U might be a reference to an integer type, if we're assigning from
     // something passed by reference.
-    typedef typename remove_reference<U>::type V; // V for "value"
-    static_assert(is_integral<V>::value, "Must be assigning from an integral type");
+    typedef typename std::remove_reference<U>::type V; // V for "value"
+    static_assert(std::is_integral<V>::value, "Must be assigning from an integral type");
 
     // We want to check that "arg" can fit inside T but without doing any tests
     // that are always true or always false due to the types involved, which
@@ -64,44 +63,44 @@ bool CanCastTo(U arg)
     // of T and V is signed and the other is unsigned: there might not be a
     // single integer type that can represent _both_ the value of arg and the
     // minimal/maximal value.
-    if (numeric_limits<T>::is_signed && numeric_limits<V>::is_signed)
+    if (std::numeric_limits<T>::is_signed && std::numeric_limits<V>::is_signed)
     {
-        if (static_cast<intmax_t>(numeric_limits<V>::max()) <= static_cast<intmax_t>(numeric_limits<T>::max()) &&
-            static_cast<intmax_t>(numeric_limits<V>::min()) >= static_cast<intmax_t>(numeric_limits<T>::min()))
+        if (static_cast<intmax_t>(std::numeric_limits<V>::max()) <= static_cast<intmax_t>(std::numeric_limits<T>::max()) &&
+            static_cast<intmax_t>(std::numeric_limits<V>::min()) >= static_cast<intmax_t>(std::numeric_limits<T>::min()))
         {
             // Any checks on arg would be trivially true; don't even do them, to
             // avoid warnings.
             return true;
         }
 
-        return static_cast<intmax_t>(numeric_limits<T>::min()) <= static_cast<intmax_t>(arg) &&
-            static_cast<intmax_t>(arg) <= static_cast<intmax_t>(numeric_limits<T>::max());
+        return static_cast<intmax_t>(std::numeric_limits<T>::min()) <= static_cast<intmax_t>(arg) &&
+            static_cast<intmax_t>(arg) <= static_cast<intmax_t>(std::numeric_limits<T>::max());
     }
 
-    if (!numeric_limits<T>::is_signed && !numeric_limits<V>::is_signed)
+    if (!std::numeric_limits<T>::is_signed && !std::numeric_limits<V>::is_signed)
     {
-        if (static_cast<uintmax_t>(numeric_limits<V>::max()) <= static_cast<uintmax_t>(numeric_limits<T>::max()))
+        if (static_cast<uintmax_t>(std::numeric_limits<V>::max()) <= static_cast<uintmax_t>(std::numeric_limits<T>::max()))
         {
             // Any checks on arg would be trivially true; don't even do them, to
             // avoid warnings.
             return true;
         }
 
-        return static_cast<uintmax_t>(arg) <= static_cast<uintmax_t>(numeric_limits<T>::max());
+        return static_cast<uintmax_t>(arg) <= static_cast<uintmax_t>(std::numeric_limits<T>::max());
     }
 
-    if (numeric_limits<T>::is_signed)
+    if (std::numeric_limits<T>::is_signed)
     {
-        static_assert(numeric_limits<T>::max() >= 0, "What weird type is this?");
-        if (static_cast<uintmax_t>(numeric_limits<V>::max()) <= static_cast<uintmax_t>(numeric_limits<T>::max()))
+        static_assert(std::numeric_limits<T>::max() >= 0, "What weird type is this?");
+        if (static_cast<uintmax_t>(std::numeric_limits<V>::max()) <= static_cast<uintmax_t>(std::numeric_limits<T>::max()))
         {
             return true;
         }
 
-        return static_cast<uintmax_t>(arg) <= static_cast<uintmax_t>(numeric_limits<T>::max());
+        return static_cast<uintmax_t>(arg) <= static_cast<uintmax_t>(std::numeric_limits<T>::max());
     }
 
-    return 0 <= arg && static_cast<uintmax_t>(arg) <= static_cast<uintmax_t>(numeric_limits<T>::max());
+    return 0 <= arg && static_cast<uintmax_t>(arg) <= static_cast<uintmax_t>(std::numeric_limits<T>::max());
 }
 
 template <typename T, typename U, std::enable_if_t<std::is_enum<T>::value, int> = 0>
@@ -127,10 +126,9 @@ bool CanCastTo(U arg)
 template <typename T>
 typename std::enable_if<std::is_unsigned<T>::value, typename std::make_signed<T>::type>::type CastToSigned(T arg)
 {
-    using namespace std;
-    typedef typename make_signed<T>::type signed_type;
+    typedef typename std::make_signed<T>::type signed_type;
 
-    if (arg <= static_cast<T>(numeric_limits<signed_type>::max()))
+    if (arg <= static_cast<T>(std::numeric_limits<signed_type>::max()))
     {
         return static_cast<signed_type>(arg);
     }
@@ -142,7 +140,7 @@ typename std::enable_if<std::is_unsigned<T>::value, typename std::make_signed<T>
     //
     // then noting that both (numeric_limits<T>::max() - arg) and its negation
     // are guaranteed to fit in signed_type.
-    signed_type diff = static_cast<signed_type>(numeric_limits<T>::max() - arg);
+    signed_type diff = static_cast<signed_type>(std::numeric_limits<T>::max() - arg);
     return static_cast<signed_type>(-diff - 1);
 }