diff --git a/requests/defaults.py b/requests/defaults.py
index 0d53dfc9..c99786f0 100644
--- a/requests/defaults.py
+++ b/requests/defaults.py
@@ -39,3 +39,4 @@ defaults['timeout_fallback'] = True
 defaults['pool_connections'] = 10
 defaults['pool_maxsize'] = 1
 defaults['max_retries'] = 0
+defaults['safe_mode'] = False