diff --git a/include/cantera/transport/TransportFactory.h b/include/cantera/transport/TransportFactory.h
index f095a19e8..7ff10948c 100644
--- a/include/cantera/transport/TransportFactory.h
+++ b/include/cantera/transport/TransportFactory.h
@@ -174,6 +174,7 @@ private:
      * instance of TransportParams containing the transport data for
      * these species read from the file.
      *
+     *  @param thermo      The phase with species corresponding to the transport data
      *  @param xspecies    Vector of pointers to species XML_Node databases.
      *  @param log         reference to an XML_Node that will contain the log (unused)
      *  @param names       vector of species names that must be filled in with valid transport parameters
@@ -181,7 +182,7 @@ private:
      *                     for the species listed in names (in the order of their listing
      *                     in names).
      */
-    void getTransportData(const std::vector<const XML_Node*> &xspecies,
+    void getTransportData(const ThermoPhase& thermo, const std::vector<const XML_Node*> &xspecies,
                           XML_Node& log, const std::vector<std::string>& names,
                           GasTransportParams& tr);
 
diff --git a/interfaces/cython/cantera/test/test_transport.py b/interfaces/cython/cantera/test/test_transport.py
index d7fcc7960..090469737 100644
--- a/interfaces/cython/cantera/test/test_transport.py
+++ b/interfaces/cython/cantera/test/test_transport.py
@@ -43,6 +43,53 @@ class TestTransport(utilities.CanteraTest):
         self.assertTrue(all(self.phase.multi_diff_coeffs.flat >= 0.0))
         self.assertTrue(all(self.phase.thermal_diff_coeffs.flat != 0.0))
 
+class TestTransportGeometryFlags(utilities.CanteraTest):
+    phase_data = """
+units(length="cm", time="s", quantity="mol", act_energy="cal/mol")
+
+ideal_gas(name="test",
+    elements="O  H",
+    species="H2  H  H2O",
+    initial_state=state(temperature=300.0, pressure=OneAtm),
+    transport='Mix'
+)
+
+species(name="H2",
+    atoms=" H:2 ",
+    thermo=const_cp(t0=1000, h0=51.7, s0=19.5, cp0=8.41),
+    transport=gas_transport(
+                geom="{H2}",
+                diam=2.92, well_depth=38.00, polar=0.79, rot_relax=280.00)
+)
+
+species(name="H",
+    atoms=" H:1 ",
+    thermo=const_cp(t0=1000, h0=51.7, s0=19.5, cp0=8.41),
+    transport=gas_transport(
+                geom="{H}",
+                diam=2.05, well_depth=145.00)
+)
+species(name="H2O",
+    atoms=" H:2  O:1 ",
+    thermo=const_cp(t0=1000, h0=51.7, s0=19.5, cp0=8.41),
+    transport=gas_transport(
+                geom="{H2O}",
+                diam=2.60, well_depth=572.40, dipole=1.84, rot_relax=4.00)
+)
+"""
+    def test_bad_geometry(self):
+        ct.Solution(source=self.phase_data.format(H='atom',
+                                                  H2='linear',
+                                                  H2O='nonlinear'))
+        bad = [{'H':'linear', 'H2':'linear', 'H2O':'nonlinear'},
+               {'H':'nonlinear', 'H2':'linear', 'H2O':'nonlinear'},
+               {'H':'atom', 'H2':'atom', 'H2O':'nonlinear'},
+               {'H':'atom', 'H2':'nonlinear', 'H2O':'nonlinear'},
+               {'H':'atom', 'H2':'linear', 'H2O':'atom'}]
+        for geoms in bad:
+            with self.assertRaises(RuntimeError):
+                ct.Solution(source=self.phase_data.format(**geoms))
+
 
 class TestDustyGas(utilities.CanteraTest):
     def setUp(self):
diff --git a/src/transport/TransportFactory.cpp b/src/transport/TransportFactory.cpp
index e86437be7..9d284a92b 100644
--- a/src/transport/TransportFactory.cpp
+++ b/src/transport/TransportFactory.cpp
@@ -437,7 +437,7 @@ void TransportFactory::setupMM(const std::vector<const XML_Node*> &transport_dat
     tr.w_ac.resize(nsp);
 
     XML_Node root, log;
-    getTransportData(transport_database, log, tr.thermo->speciesNames(), tr);
+    getTransportData(*thermo, transport_database, log, tr.thermo->speciesNames(), tr);
 
     for (size_t i = 0; i < nsp; i++) {
         tr.poly[i].resize(nsp);
@@ -687,7 +687,7 @@ void TransportFactory::fitCollisionIntegrals(GasTransportParams& tr,
     }
 }
 
-void TransportFactory::getTransportData(const std::vector<const XML_Node*> &xspecies,
+void TransportFactory::getTransportData(const ThermoPhase& thermo, const std::vector<const XML_Node*> &xspecies,
                                         XML_Node& log, const std::vector<std::string> &names, GasTransportParams& tr)
 {
     std::map<std::string, size_t> speciesIndices;
@@ -713,14 +713,32 @@ void TransportFactory::getTransportData(const std::vector<const XML_Node*> &xspe
 
         // parameters are converted to SI units before storing
 
+        double nAtoms = 0;
+        size_t kSpec = thermo.speciesIndex(sp["name"]);
+        for (size_t m = 0; m < thermo.nElements(); m++) {
+            nAtoms += thermo.nAtoms(kSpec, m);
+        }
+
         // Molecular geometry; rotational heat capacity / R
         XML_Node* geomNode = ctml::getByTitle(node, "geometry");
         std::string geom = (geomNode) ? geomNode->value() : "";
         if (geom == "atom") {
+            if (nAtoms != 1) {
+                throw TransportDBError(i, "invalid geometry. 'atom' specified,"
+                    " but species contains multiple atoms.");
+            }
             tr.crot[j] = 0.0;
         } else if (geom == "linear") {
+            if (nAtoms == 1) {
+                throw TransportDBError(i, "invalid geometry. 'linear' specified,"
+                    " but species only contains one atom.");
+            }
             tr.crot[j] = 1.0;
         } else if (geom == "nonlinear") {
+            if (nAtoms < 3) {
+                throw TransportDBError(i, "invalid geometry. 'nonlinear' specified,"
+                    " but species only contains " + fp2str(nAtoms) + " atoms.");
+            }
             tr.crot[j] = 1.5;
         } else {
             throw TransportDBError(i, "invalid geometry");