diff --git a/test/ca_certs_manager_test.cpp b/test/ca_certs_manager_test.cpp
index 17c8589..5bdad56 100644
--- a/test/ca_certs_manager_test.cpp
+++ b/test/ca_certs_manager_test.cpp
@@ -10,9 +10,12 @@
 
 #include <gtest/gtest.h>
 
+namespace ca::cert
+{
+namespace
+{
 using InvalidArgument =
     sdbusplus::xyz::openbmc_project::Common::Error::InvalidArgument;
-using namespace ca::cert;
 
 class MockCACertMgr : public CACertMgr
 {
@@ -123,3 +126,5 @@
     manager.erase(std::stoi(id));
     EXPECT_TRUE(manager.getNumOfEntries() == 0);
 }
+} // namespace
+} // namespace ca::cert
diff --git a/test/certs_manager_test.cpp b/test/certs_manager_test.cpp
index 38c563a..1131df1 100644
--- a/test/certs_manager_test.cpp
+++ b/test/certs_manager_test.cpp
@@ -20,12 +20,16 @@
 #include <xyz/openbmc_project/Common/error.hpp>
 
 #include <gtest/gtest.h>
+
+namespace phosphor::certs
+{
+namespace
+{
 namespace fs = std::filesystem;
 using InternalFailure =
     sdbusplus::xyz::openbmc_project::Common::Error::InternalFailure;
 using InvalidCertificate =
     sdbusplus::xyz::openbmc_project::Certs::Error::InvalidCertificate;
-using namespace phosphor::certs;
 
 /**
  * Class to generate certificate file and test verification of certificate file
@@ -1380,3 +1384,5 @@
                     std::move(installPath));
     EXPECT_TRUE(fs::exists(rsaPrivateKeyFilePath));
 }
+} // namespace
+} // namespace phosphor::certs