diff --git a/.github/workflows/clang-tidy.yaml b/.github/workflows/clang-tidy.yaml
index 3d296602b8..1172cf0eb2 100644
--- a/.github/workflows/clang-tidy.yaml
+++ b/.github/workflows/clang-tidy.yaml
@@ -17,9 +17,9 @@ jobs:
       matrix:
         include:
           - cmake_options: all-options-abiv1-preview
-            warning_limit: 142
+            warning_limit: 139
           - cmake_options: all-options-abiv2-preview
-            warning_limit: 152
+            warning_limit: 149
     env:
       CC: /usr/bin/clang-22
       CXX: /usr/bin/clang++-22
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8baba4503c..7917275c45 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -51,6 +51,10 @@ Increment the:
 * [CODE HEALTH] Fix remaining misc-override-with-different-visibility warnings
   [#4280](https://github.com/open-telemetry/opentelemetry-cpp/pull/4280)
 
+* [CODE HEALTH] Move SDK common and logs test helpers into anonymous
+  namespaces
+  [#4302](https://github.com/open-telemetry/opentelemetry-cpp/pull/4302)
+
 Breaking changes:
 
 * [METRICS SDK] Rename Base2 Exponential Histogram Aggregation config field
diff --git a/sdk/test/common/global_log_handle_singleton_lifetime_test.cc b/sdk/test/common/global_log_handle_singleton_lifetime_test.cc
index 1aac3ee412..b5f5e64daf 100644
--- a/sdk/test/common/global_log_handle_singleton_lifetime_test.cc
+++ b/sdk/test/common/global_log_handle_singleton_lifetime_test.cc
@@ -11,6 +11,9 @@
 #include "opentelemetry/sdk/common/attribute_utils.h"
 #include "opentelemetry/sdk/common/global_log_handler.h"
 
+namespace
+{
+
 class GlobalLogHandlerChecker
 {
 public:
@@ -19,9 +22,12 @@ class GlobalLogHandlerChecker
   {
     using opentelemetry::sdk::common::internal_log::GlobalLogHandler;
     auto handle = GlobalLogHandler::GetLogHandler();
-    if (handle && custom_handler_destroyed)
+    // The checker must outlive the global handler. Fail if it is destroyed first
+    // (custom_handler_destroyed still false) or if the handler is somehow still reachable
+    // (handle non-null).
+    if (!custom_handler_destroyed || handle)
     {
-      OTEL_INTERNAL_LOG_ERROR("GlobalLogHandler should be destroyed here");
+      OTEL_INTERNAL_LOG_ERROR("GlobalLogHandler must be destroyed before the checker");
       abort();
     }
     std::cout << "GlobalLogHandlerChecker destroyed and check pass.\n";
@@ -38,14 +44,11 @@ class GlobalLogHandlerChecker
 };
 bool GlobalLogHandlerChecker::custom_handler_destroyed = false;
 
-namespace
-{
 static GlobalLogHandlerChecker &ConstructChecker()
 {
   static GlobalLogHandlerChecker checker;
   return checker;
 }
-}  // namespace
 
 class CustomLogHandler : public opentelemetry::sdk::common::internal_log::LogHandler
 {
@@ -112,3 +115,5 @@ TEST(GlobalLogHandleSingletonTest, Lifetime)
     EXPECT_TRUE(!!handle);
   }
 }
+
+}  // namespace
diff --git a/sdk/test/logs/logger_provider_set_test.cc b/sdk/test/logs/logger_provider_set_test.cc
index aa899bbcbd..bb849549fb 100644
--- a/sdk/test/logs/logger_provider_set_test.cc
+++ b/sdk/test/logs/logger_provider_set_test.cc
@@ -28,6 +28,9 @@ namespace nostd    = opentelemetry::nostd;
 namespace logs_api = opentelemetry::logs;
 namespace logs_sdk = opentelemetry::sdk::logs;
 
+namespace
+{
+
 class TestProvider : public LoggerProvider
 {
 public:
@@ -86,3 +89,5 @@ TEST(Provider, MultipleLoggerProviders)
 
   ASSERT_NE(logs_api::Provider::GetLoggerProvider(), tf);
 }
+
+}  // namespace