diff --git a/sdk/cosmos/azure-cosmos/tests/test_availability_strategy.py b/sdk/cosmos/azure-cosmos/tests/test_availability_strategy.py
index 53ef61bb88a4..4637b77bc57e 100644
--- a/sdk/cosmos/azure-cosmos/tests/test_availability_strategy.py
+++ b/sdk/cosmos/azure-cosmos/tests/test_availability_strategy.py
@@ -9,6 +9,7 @@
 import uuid
 from concurrent.futures import ThreadPoolExecutor
 from typing import Optional, Any, Union
+from unittest.mock import patch
 
 import pytest
 from azure.core.exceptions import ServiceResponseError
@@ -716,9 +717,12 @@ def test_no_cross_region_request_with_retry_write_disabled(self, operation):
     @pytest.mark.parametrize("operation", [READ, QUERY_PK, CHANGE_FEED, CREATE, UPSERT, REPLACE, DELETE, PATCH, BATCH])
     def test_per_partition_circular_breaker_with_cancelled_first_future(self, operation):
         # QUERY, READ_ALL are not included because currently they are not targeting to a specific pkRange
-        os.environ["AZURE_COSMOS_ENABLE_CIRCUIT_BREAKER"] = "True"
-        os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_WRITE"] = "5"
-        os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_READ"] = "5"
+        env_patch = patch.dict(os.environ, {
+            "AZURE_COSMOS_ENABLE_CIRCUIT_BREAKER": "True",
+            "AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_WRITE": "5",
+            "AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_READ": "5",
+        })
+        env_patch.start()
 
         try:
             """Test that when per partition circular breaker is enabled and after hitting the threshold, subsequent requests go directly to second region.
@@ -799,9 +803,7 @@ def test_per_partition_circular_breaker_with_cancelled_first_future(self, operat
                     availability_strategy=strategy)
 
         finally:
-            del os.environ["AZURE_COSMOS_ENABLE_CIRCUIT_BREAKER"]
-            del os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_WRITE"]
-            del os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_READ"]
+            env_patch.stop()
 
         self._clean_up_container(setup_with_fault_injection['db'].id, setup_with_fault_injection['col'].id)
 
diff --git a/sdk/cosmos/azure-cosmos/tests/test_availability_strategy_async.py b/sdk/cosmos/azure-cosmos/tests/test_availability_strategy_async.py
index 2017c6d7a9dd..46eab5e94080 100644
--- a/sdk/cosmos/azure-cosmos/tests/test_availability_strategy_async.py
+++ b/sdk/cosmos/azure-cosmos/tests/test_availability_strategy_async.py
@@ -7,6 +7,7 @@
 import unittest
 import uuid
 from typing import Optional, Any, Union
+from unittest.mock import patch
 
 import pytest
 import pytest_asyncio
@@ -847,9 +848,12 @@ async def test_no_cross_region_request_with_exclude_regions_async(self, operatio
     @pytest.mark.parametrize("operation", [READ, QUERY_PK, CHANGE_FEED, CREATE, UPSERT, REPLACE, DELETE, PATCH, BATCH])
     async def test_per_partition_circular_breaker_with_cancelled_first_future_async(self, operation, setup):
         # QUERY, READ_ALL are not included because currently they are not targeting to a specific pkRange
-        os.environ["AZURE_COSMOS_ENABLE_CIRCUIT_BREAKER"] = "True"
-        os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_WRITE"] = "5"
-        os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_READ"] = "5"
+        env_patch = patch.dict(os.environ, {
+            "AZURE_COSMOS_ENABLE_CIRCUIT_BREAKER": "True",
+            "AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_WRITE": "5",
+            "AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_READ": "5",
+        })
+        env_patch.start()
 
         try:
             """Test that when per partition circular breaker is enabled and after hitting the threshold, subsequent requests go directly to second region.
@@ -938,9 +942,7 @@ async def test_per_partition_circular_breaker_with_cancelled_first_future_async(
             await setup_with_fault_injection['client'].close()
             await setup_without_fault['client'].close()
         finally:
-            del os.environ["AZURE_COSMOS_ENABLE_CIRCUIT_BREAKER"]
-            del os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_WRITE"]
-            del os.environ["AZURE_COSMOS_CONSECUTIVE_ERROR_COUNT_TOLERATED_FOR_READ"]
+            env_patch.stop()
         await self._clean_up_container(setup['client_without_fault'], setup_with_fault_injection['db'].id, setup_with_fault_injection['col'].id)
 
     @pytest.mark.asyncio