diff --git a/openmc/data/neutron.py b/openmc/data/neutron.py
index 07b1f7686a..64634f2afa 100644
--- a/openmc/data/neutron.py
+++ b/openmc/data/neutron.py
@@ -34,7 +34,7 @@ from openmc.mixin import EqualityMixin
 _RESONANCE_ENERGY_GRID = np.logspace(-3, 3, 61)
 
 
-def get_metadata(zaid, metastable_scheme='nndc'):
+def _get_metadata(zaid, metastable_scheme='nndc'):
     """Return basic identifying data for a nuclide with a given ZAID.
 
     Parameters
diff --git a/scripts/openmc-update-inputs b/scripts/openmc-update-inputs
index ea6506942d..3eb850207e 100755
--- a/scripts/openmc-update-inputs
+++ b/scripts/openmc-update-inputs
@@ -11,7 +11,6 @@ from itertools import chain
 from random import randint
 from shutil import move
 import xml.etree.ElementTree as ET
-import re
 
 import openmc.data
 
@@ -239,12 +238,6 @@ def update_geometry(geometry_root):
 
     return was_updated
 
-def replace_zaid(name):
-    """Replace a nuclide name in the ZAID notation with the correct name."""
-    zaid = int(name.strip())
-    name = openmc.data.neutron.get_metadata(zaid)[0]
-    return name
-
 def update_materials(root):
     """Update the given XML materials tree. Return True if changes were made."""
     was_updated = False
@@ -254,9 +247,11 @@ def update_materials(root):
             if 'name' in nuclide.attrib:
                 nucname = nuclide.attrib['name']
                 nucname = nucname.replace('-', '')
-                s = re.search("\s*(?<![A-z])\d{4,6}\s*", nucname)
-                if s:
-                    nucname = replace_zaid(s.group(0))
+                # If a nuclide name is in the ZAID notation (e.g., a number),
+                # convert it to the proper nuclide name.
+                if nucname.strip().isnumeric():
+                    nucname = \
+                      openmc.data.neutron._get_metadata(int(nucname))[0]
                 nucname = nucname.replace('Nat', '0')
                 if nucname.endswith('m'):
                     nucname = nucname[:-1] + '_m1'