diff --git a/gprMax/input_cmds_singleuse.py b/gprMax/input_cmds_singleuse.py
index de8f154f..279fff91 100644
--- a/gprMax/input_cmds_singleuse.py
+++ b/gprMax/input_cmds_singleuse.py
@@ -67,8 +67,9 @@ def process_singlecmds(singlecmds, G):
     if sys.platform == 'darwin':
         os.environ['OMP_WAIT_POLICY'] = 'ACTIVE'  # Should waiting threads consume CPU power (can drastically effect performance)
     os.environ['OMP_DYNAMIC'] = 'FALSE' # Number of threads may be adjusted by the run time environment to best utilize system resources
-    os.environ['OMP_PLACES'] = 'cores'
-    os.environ['OMP_PROC_BIND'] = 'spread'  # Bind threads to physical cores
+    os.environ['OMP_PLACES'] = 'cores' # Each place corresponds to a single core (having one or more hardware threads)
+    #os.environ['OMP_PLACES'] = '{0,2,4,6,8,10,12,14,16,18,20,22,24,26,28,30}'
+    os.environ['OMP_PROC_BIND'] = 'TRUE'  # Bind threads to physical cores
     # os.environ['OMP_DISPLAY_ENV'] = 'TRUE' # Prints OMP version and environment variables (useful for debug)
 
     # Catch bug with Windows Subsystem for Linux (https://github.com/gprMax/gprMax/issues/95)