diff --git a/py/desispec/test/test_binscripts.py b/py/desispec/test/test_binscripts.py
index ff0be2e7c..21523358f 100644
--- a/py/desispec/test/test_binscripts.py
+++ b/py/desispec/test/test_binscripts.py
@@ -2,6 +2,7 @@
 import os, sys
 import unittest
 from uuid import uuid4
+import shutil
 import tempfile
 
 import numpy as np
@@ -90,12 +91,11 @@ def setUpClass(cls):
     @classmethod
     def tearDownClass(cls):
         """Cleanup in case tests crashed and left files behind"""
-        os.chdir(cls.testdir)
-        for filename in [cls.framefile, cls.fiberflatfile, cls.fibermapfile, \
-            cls.skyfile, cls.calibfile, cls.stdfile, cls.qa_calib_file,
-                         cls.qa_data_file, cls.modelfile, cls.qafig]:
-            if os.path.exists(filename):
-                os.remove(filename)
+
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
+            shutil.rmtree(cls.testdir)
+
         if cls.origPath is None:
             del os.environ['PYTHONPATH']
         else:
diff --git a/py/desispec/test/test_bootcalib.py b/py/desispec/test/test_bootcalib.py
index bbc54d94b..699727b7c 100644
--- a/py/desispec/test/test_bootcalib.py
+++ b/py/desispec/test/test_bootcalib.py
@@ -5,6 +5,7 @@
 import unittest
 from uuid import uuid1
 import tempfile
+import shutil
 import os
 import numpy as np
 import glob
@@ -51,18 +52,9 @@ def setUpClass(cls):
 
     @classmethod
     def tearDownClass(cls):
-        """We deliberately don't clean up the testarc and testflat files,
-        since they are useful for offline testing.
-        """
-        os.chdir(cls.testdir)
-        # if os.path.exists(cls.testarc):
-        #     os.unlink(cls.testarc)
-        # if os.path.exists(cls.testflat):
-        #     os.unlink(cls.testflat)
-        if os.path.exists(cls.testout):
-            os.unlink(cls.testout)
-        if os.path.isfile(cls.qafile):
-            os.unlink(cls.qafile)
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
+            shutil.rmtree(cls.testdir)
 
         os.chdir(cls.origdir)
 
diff --git a/py/desispec/test/test_calibfinder.py b/py/desispec/test/test_calibfinder.py
index 334df3710..dbd379fb7 100644
--- a/py/desispec/test/test_calibfinder.py
+++ b/py/desispec/test/test_calibfinder.py
@@ -35,7 +35,7 @@ def setUpClass(cls):
     @classmethod
     def tearDownClass(cls):
         #- remove temporary calibration directory
-        if os.path.isdir(cls.calibdir) :
+        if cls.calibdir.startswith(tempfile.gettempdir()) and os.path.isdir(cls.calibdir) :
             shutil.rmtree(cls.calibdir)
 
     def tearDown(self):
diff --git a/py/desispec/test/test_extract.py b/py/desispec/test/test_extract.py
index 1e3eee939..a1baffb11 100644
--- a/py/desispec/test/test_extract.py
+++ b/py/desispec/test/test_extract.py
@@ -14,6 +14,7 @@
 import uuid
 import os
 import tempfile
+import shutil
 from glob import glob
 from importlib import resources
 
@@ -60,10 +61,9 @@ def setUp(self):
 
     @classmethod
     def tearDownClass(cls):
-        os.chdir(cls.testdir)
-        for filename in glob('test-*{}*.fits'.format(cls.testhash)):
-            if os.path.exists(filename):
-                os.remove(filename)
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
+            shutil.rmtree(cls.testdir)
 
         os.chdir(cls.origdir)
 
diff --git a/py/desispec/test/test_fiberflat.py b/py/desispec/test/test_fiberflat.py
index 5b2164e83..d9e7faf94 100644
--- a/py/desispec/test/test_fiberflat.py
+++ b/py/desispec/test/test_fiberflat.py
@@ -8,6 +8,7 @@
 import copy
 import os
 import tempfile
+import shutil
 from uuid import uuid1
 
 import numpy as np
@@ -69,6 +70,10 @@ def tearDown(self):
 
     @classmethod
     def tearDownClass(cls):
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
+            shutil.rmtree(cls.testdir)
+
         os.chdir(cls.origdir)
 
 
diff --git a/py/desispec/test/test_pixgroup.py b/py/desispec/test/test_pixgroup.py
index 273be77a0..0a6ff5a44 100644
--- a/py/desispec/test/test_pixgroup.py
+++ b/py/desispec/test/test_pixgroup.py
@@ -19,6 +19,10 @@ class TestPixGroup(unittest.TestCase):
     def setUpClass(cls):
         cls.testdir = tempfile.mkdtemp()
         cls.outdir = os.path.join(cls.testdir, 'output')
+
+        cls.origenv = dict()
+        for key in ['DESI_SPECTRO_REDUX', 'SPECPROD']:
+            cls.origenv[key] = os.getenv(key)  #- will be None if not set
         
         os.environ['DESI_SPECTRO_REDUX'] = cls.testdir
         os.environ['SPECPROD'] = 'grouptest'
@@ -136,9 +140,17 @@ def setUpClass(cls):
 
     @classmethod
     def tearDownClass(cls):
-        if os.path.exists(cls.testdir):
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
             shutil.rmtree(cls.testdir)
 
+        #- restore environment
+        for key, value in cls.origenv.items():
+            if value is not None:
+                os.environ[key] = value
+            elif key in os.environ:
+                del os.environ[key]
+
     def setUp(self):
         os.environ['DESI_SPECTRO_REDUX'] = self.testdir
         os.environ['SPECPROD'] = 'grouptest'
diff --git a/py/desispec/test/test_qlextract.py b/py/desispec/test/test_qlextract.py
index bc0007d16..edfe77ff4 100644
--- a/py/desispec/test/test_qlextract.py
+++ b/py/desispec/test/test_qlextract.py
@@ -13,6 +13,7 @@
 import uuid
 import os
 import tempfile
+import shutil
 from glob import glob
 from importlib import resources
 
@@ -56,10 +57,9 @@ def setUp(self):
 
     @classmethod
     def tearDownClass(cls):
-        os.chdir(cls.testdir)
-        for filename in glob('test-*{}*.fits'.format(cls.testhash)):
-            if os.path.exists(filename):
-                os.remove(filename)
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
+            shutil.rmtree(cls.testdir)
 
         os.chdir(cls.origdir)
 
diff --git a/py/desispec/test/test_scripts.py b/py/desispec/test/test_scripts.py
index 46cde5e13..a3f3b2359 100644
--- a/py/desispec/test/test_scripts.py
+++ b/py/desispec/test/test_scripts.py
@@ -8,6 +8,7 @@
 import os
 import unittest
 import tempfile
+import shutil
 from uuid import uuid4
 from astropy.table import Table
 
@@ -29,6 +30,10 @@ def setUpClass(cls):
 
     @classmethod
     def tearDownClass(cls):
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
+            shutil.rmtree(cls.testdir)
+
         cls.environ_cache.clear()
         os.chdir(cls.origdir)
 
diff --git a/py/desispec/test/test_spectra.py b/py/desispec/test/test_spectra.py
index 0328daab4..e5f8ed0fb 100644
--- a/py/desispec/test/test_spectra.py
+++ b/py/desispec/test/test_spectra.py
@@ -74,7 +74,8 @@ def tearDownClass(cls):
             else:
                 os.environ[e] = cls.origEnv[e]
 
-        if os.path.exists(cls.testDir):
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testDir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testDir):
             shutil.rmtree(cls.testDir)
 
         os.chdir(cls.origDir)
diff --git a/py/desispec/test/test_util.py b/py/desispec/test/test_util.py
index 71ecea9c9..fa1bcb1f5 100644
--- a/py/desispec/test/test_util.py
+++ b/py/desispec/test/test_util.py
@@ -8,6 +8,7 @@
 from uuid import uuid4
 import importlib
 import tempfile
+import shutil
 
 import numpy as np
 from astropy.table import Table
@@ -295,10 +296,9 @@ def setUp(self):
 
     @classmethod
     def tearDownClass(cls):
-        os.chdir(cls.testdir)
-        for filename in [cls.infile, cls.outfile, cls.testfile]:
-            if os.path.exists(filename):
-                os.remove(filename)
+        #- Remove testdir only if it was created by tempfile.mkdtemp
+        if cls.testdir.startswith(tempfile.gettempdir()) and os.path.exists(cls.testdir):
+            shutil.rmtree(cls.testdir)
 
         os.chdir(cls.origdir)