diff --git a/process/core/init.py b/process/core/init.py
index cd1c236e4..afce8204b 100644
--- a/process/core/init.py
+++ b/process/core/init.py
@@ -22,6 +22,7 @@
 )
 from process.data_structure.impurity_radiation_variables import N_IMPURITIES
 from process.data_structure.numerics import FiguresOfMerit, PROCESSRunMode
+from process.data_structure.pfcoil_variables import PFConductorModel
 from process.data_structure.physics_variables import DivertorNumberModels
 from process.models.pfcoil import PFLocationTypes
 from process.models.physics.profiles import DensityProfilePedestalType
@@ -978,7 +979,7 @@ def check_process(inputs, data):  # noqa: ARG001
         )
 
     # PF coil resistivity is zero if superconducting
-    if data.pf_coil.i_pf_conductor == 0:
+    if data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
         data.pf_coil.rho_pf_coil = 0.0
 
     # If there is no NBI, then hot beam density should be zero
diff --git a/process/data_structure/pfcoil_variables.py b/process/data_structure/pfcoil_variables.py
index 845b6aa2d..e32f8db8f 100644
--- a/process/data_structure/pfcoil_variables.py
+++ b/process/data_structure/pfcoil_variables.py
@@ -1,7 +1,19 @@
 from dataclasses import dataclass, field
+from enum import IntEnum
 
 import numpy as np
 
+
+class PFConductorModel(IntEnum):
+    """Enumeration for PF conductor models.
+    Controlled via `i_pf_conductor`
+
+    """
+
+    SUPERCONDUCTING = 0
+    RESISTIVE = 1
+
+
 N_PF_GROUPS_MAX = 10
 """maximum number of groups of PF coils"""
 
@@ -317,7 +329,7 @@ class PFCoilData:
     """steel case thickness for PF coil i (m)"""
 
     rho_pf_coil: float = 2.5e-8
-    """PF coil resistivity (if i_pf_conductor=1) (Ohm-m)"""
+    """PF coil resistivity (if i_pf_conductor=1/RESISTIVE) (Ohm-m)"""
 
     rhopfbus: float = 3.93e-8
     """Resistivity of CS and PF coil bus bars (irrespective of
diff --git a/process/models/costs/costs.py b/process/models/costs/costs.py
index 47ca87bd2..f9ca23654 100644
--- a/process/models/costs/costs.py
+++ b/process/models/costs/costs.py
@@ -6,6 +6,7 @@
 from process.core import process_output as po
 from process.core.exceptions import ProcessValueError
 from process.core.model import Model
+from process.data_structure.pfcoil_variables import PFConductorModel
 from process.models.tfcoil.base import TFConductorModel
 
 logger = logging.getLogger(__name__)
@@ -1612,7 +1613,9 @@ def acc2222(self):
         #  each superconducting cable (so is zero for resistive coils)
 
         costpfsh = (
-            0.0 if self.data.pf_coil.i_pf_conductor == 1 else self.data.costs.cconshpf
+            0.0
+            if self.data.pf_coil.i_pf_conductor == PFConductorModel.RESISTIVE
+            else self.data.costs.cconshpf
         )
 
         #  Non-Central Solenoid coils
@@ -1627,7 +1630,7 @@ def acc2222(self):
         for i in range(npf):
             #  Superconductor ($/m)
             if self.data.costs.supercond_cost_model == 0:
-                if self.data.pf_coil.i_pf_conductor == 0:
+                if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                     costpfsc = (
                         self.data.costs.ucsc[self.data.pf_coil.i_pf_superconductor - 1]
                         * (1.0e0 - self.data.pf_coil.fcupfsu)
@@ -1644,7 +1647,7 @@ def acc2222(self):
                     )
                 else:
                     costpfsc = 0.0e0
-            elif self.data.pf_coil.i_pf_conductor == 0:
+            elif self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                 costpfsc = (
                     self.data.costs.sc_mat_cost_0[
                         self.data.pf_coil.i_pf_superconductor - 1
@@ -1658,7 +1661,7 @@ def acc2222(self):
                 costpfsc = 0.0
 
             #  Copper ($/m)
-            if self.data.pf_coil.i_pf_conductor == 0:
+            if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                 costpfcu = (
                     self.data.costs.uccu
                     * self.data.pf_coil.fcupfsu
@@ -1709,7 +1712,7 @@ def acc2222(self):
             #  Superconductor ($/m)
             if self.data.costs.supercond_cost_model == 0:
                 #  Issue #328  Use CS conductor cross-sectional area (m2)
-                if self.data.pf_coil.i_pf_conductor == 0:
+                if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                     costpfsc = (
                         self.data.costs.ucsc[self.data.pf_coil.i_cs_superconductor - 1]
                         * self.data.pf_coil.a_cs_cable_space
@@ -1724,7 +1727,7 @@ def acc2222(self):
                     )
                 else:
                     costpfsc = 0.0e0
-            elif self.data.pf_coil.i_pf_conductor == 0:
+            elif self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                 costpfsc = (
                     self.data.costs.sc_mat_cost_0[
                         self.data.pf_coil.i_cs_superconductor - 1
@@ -1739,7 +1742,7 @@ def acc2222(self):
 
             #  Copper ($/m)
 
-            if self.data.pf_coil.i_pf_conductor == 0:
+            if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                 costpfcu = (
                     self.data.costs.uccu
                     * self.data.pf_coil.a_cs_cable_space
diff --git a/process/models/pfcoil.py b/process/models/pfcoil.py
index d738c4670..89c558760 100644
--- a/process/models/pfcoil.py
+++ b/process/models/pfcoil.py
@@ -20,6 +20,7 @@
     NFIXMX,
     NGC2,
     NPTSMX,
+    PFConductorModel,
 )
 from process.models import superconductors
 from process.models.superconductors import SuperconductorMaterial, SuperconductorModel
@@ -864,7 +865,7 @@ def pfcoil(self):
 
                 # Issue 1871.  MDK
                 # Allowable current density (for superconducting coils) for each coil, index i
-                if self.data.pf_coil.i_pf_conductor == 0:
+                if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                     bmax = max(
                         abs(self.data.pf_coil.b_pf_coil_peak[i]),
                         abs(self.data.pf_coil.bpf2[i]),
@@ -910,7 +911,7 @@ def pfcoil(self):
 
                 # Resistive coils
 
-                if self.data.pf_coil.i_pf_conductor == 1:
+                if self.data.pf_coil.i_pf_conductor == PFConductorModel.RESISTIVE:
                     # Coil resistance (f_a_pf_coil_void is the void fraction)
 
                     respf = (
@@ -937,7 +938,7 @@ def pfcoil(self):
 
                 # Conductor weight (f_a_pf_coil_void is the void fraction)
 
-                if self.data.pf_coil.i_pf_conductor == 0:
+                if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                     self.data.pf_coil.m_pf_coil_conductor[i] = (
                         volpf
                         * self.data.tfcoil.dcond[
@@ -963,7 +964,7 @@ def pfcoil(self):
 
                 # Stress ==> cross-sectional area of supporting steel to use
 
-                if self.data.pf_coil.i_pf_conductor == 0:
+                if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                     # Superconducting coil
                     # Updated assumptions: 500 MPa stress limit with all of the force
                     # supported in the conduit (steel) case.
@@ -2035,7 +2036,7 @@ def outpf(self):
         if self.data.build.iohcl == 0:
             op.ocmmnt(self.outfile, "No central solenoid included")
             op.oblnkl(self.outfile)
-        elif self.data.pf_coil.i_pf_conductor == 0:
+        elif self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
             op.ocmmnt(self.outfile, "Superconducting central solenoid")
 
             op.ovarin(
@@ -2330,7 +2331,7 @@ def outpf(self):
         op.ocmmnt(self.outfile, "----------------------------")
         op.oblnkl(self.outfile)
 
-        if self.data.pf_coil.i_pf_conductor == 0:
+        if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
             op.oblnkl(self.outfile)
             op.ocmmnt(self.outfile, "Superconducting PF coils")
 
@@ -2557,7 +2558,7 @@ def outpf(self):
 
         # PF coils
         for k in range(self.data.pf_coil.nef):
-            if self.data.pf_coil.i_pf_conductor == 0:
+            if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                 rows.append([
                     f"PF {k}",
                     f"{self.data.pf_coil.c_pf_cs_coils_peak_ma[k]:.3e}",
@@ -2587,7 +2588,7 @@ def outpf(self):
                 abs(self.data.pf_coil.j_cs_pulse_start),
                 abs(self.data.pf_coil.j_cs_flat_top_end),
             )
-            if self.data.pf_coil.i_pf_conductor == 0:
+            if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                 # Issue #328
                 rows.append([
                     "CS",
@@ -3361,7 +3362,7 @@ def ohcalc(self):
         )
 
         # Stress ==> cross-sectional area of supporting steel to use
-        if self.data.pf_coil.i_pf_conductor == 0:
+        if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
             # Superconducting coil
 
             # New calculation from M. N. Wilson for hoop stress
@@ -3477,7 +3478,7 @@ def ohcalc(self):
             )
 
         # Weight of conductor in central Solenoid
-        if self.data.pf_coil.i_pf_conductor == 0:
+        if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
             self.data.pf_coil.m_pf_coil_conductor[
                 self.data.pf_coil.n_cs_pf_coils - 1
             ] = (
@@ -3500,7 +3501,7 @@ def ohcalc(self):
                 * constants.den_copper
             )
 
-        if self.data.pf_coil.i_pf_conductor == 0:
+        if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
             # Allowable coil overall current density at EOF
             # (superconducting coils only)
 
diff --git a/process/models/power.py b/process/models/power.py
index e807ce843..bf8e81ae3 100644
--- a/process/models/power.py
+++ b/process/models/power.py
@@ -12,7 +12,7 @@
 from process.core.exceptions import ProcessValueError
 from process.core.model import Model
 from process.data_structure.blanket_variables import BlktModelTypes
-from process.data_structure.pfcoil_variables import NGC2
+from process.data_structure.pfcoil_variables import NGC2, PFConductorModel
 
 
 class PumpingPowerModelTypes(IntEnum):
@@ -1028,7 +1028,10 @@ def calculate_cryo_loads(self):
         self.data.tfcoil.cryo_cool_req = 0.0e0
 
         # Superconductors TF/PF cryogenic cooling
-        if self.data.tfcoil.i_tf_sup == 1 or self.data.pf_coil.i_pf_conductor == 0:
+        if (
+            self.data.tfcoil.i_tf_sup == 1
+            or self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING
+        ):
             # self.data.heat_transport.helpow calculation
             self.data.heat_transport.helpow = self.cryo(
                 self.data.tfcoil.i_tf_sup,
diff --git a/process/models/pulse.py b/process/models/pulse.py
index 78ec3cb99..46741b8eb 100644
--- a/process/models/pulse.py
+++ b/process/models/pulse.py
@@ -5,6 +5,7 @@
 from process.core import constants
 from process.core import process_output as po
 from process.core.model import Model
+from process.data_structure.pfcoil_variables import PFConductorModel
 
 logger = logging.getLogger(__name__)
 
@@ -67,7 +68,7 @@ def tohswg(self, output: bool):
 
         #  Central Solenoid resistance (ohms)
 
-        if self.data.pf_coil.i_pf_conductor == 0:
+        if self.data.pf_coil.i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
             r = 0.0e0
         else:
             r = (
diff --git a/process/models/structure.py b/process/models/structure.py
index 6a3815a47..1489b3db6 100644
--- a/process/models/structure.py
+++ b/process/models/structure.py
@@ -8,6 +8,7 @@
 from process.core import constants
 from process.core import process_output as po
 from process.core.model import Model
+from process.data_structure.pfcoil_variables import PFConductorModel
 
 logger = logging.getLogger(__name__)
 
@@ -163,7 +164,7 @@ def structure(
         coldmass = 0.0e0
         if i_tf_sup == 1:
             coldmass = coldmass + tfmass + aintmass + dewmass
-        if i_pf_conductor != 1:
+        if i_pf_conductor != PFConductorModel.RESISTIVE:
             coldmass += pfmass
 
         #  Coil gravity support mass
diff --git a/process/models/tfcoil/base.py b/process/models/tfcoil/base.py
index 87be5d730..cba4e3950 100644
--- a/process/models/tfcoil/base.py
+++ b/process/models/tfcoil/base.py
@@ -17,6 +17,7 @@
 from process.core.exceptions import ProcessValueError
 from process.core.model import DataStructure, Model
 from process.data_structure.build_variables import TFCSRadialConfiguration
+from process.data_structure.pfcoil_variables import PFConductorModel
 from process.data_structure.physics_variables import DivertorNumberModels
 
 logger = logging.getLogger(__name__)
@@ -2538,7 +2539,7 @@ def stresscl(
                 radtf[0] = dr_bore
 
             # Superconducting CS
-            if i_pf_conductor == 0:
+            if i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
                 # Getting the turn dimention from scratch
                 # as the TF is called before CS in caller.f90
                 # -#
@@ -3049,7 +3050,7 @@ def stresscl(
         # --------------------------------
         # SC central solenoid coil stress unsmearing (bucked and wedged only)
         # ---
-        if i_tf_bucking >= 2 and i_pf_conductor == 0:
+        if i_tf_bucking >= 2 and i_pf_conductor == PFConductorModel.SUPERCONDUCTING:
             # Central Solenoid (OH) steel conduit stress unsmearing factors
             for ii in range(n_radial_array):
                 sig_tf_r[ii] = sig_tf_r[ii] * eyoung_cs_stiffest_leg / eyoung_axial[0]
diff --git a/tests/unit/models/test_costs_1990.py b/tests/unit/models/test_costs_1990.py
index 10c987c60..dccefbbcf 100644
--- a/tests/unit/models/test_costs_1990.py
+++ b/tests/unit/models/test_costs_1990.py
@@ -5,6 +5,7 @@
 import numpy as np
 import pytest
 
+from process.data_structure.pfcoil_variables import PFConductorModel
 from process.models.engineering.pumping import CoolantType
 
 
@@ -2144,7 +2145,7 @@ class Acc2222Param(NamedTuple):
             supercond_cost_model=0,
             j_crit_str_cs=100.0,
             j_crit_str_pf=200.0,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             f_a_cs_void=0.29999999999999999,
             n_cs_pf_coils=7,
             n_pf_coil_turns=np.array(
@@ -2340,7 +2341,7 @@ class Acc2222Param(NamedTuple):
             supercond_cost_model=0,
             j_crit_str_cs=100.0,
             j_crit_str_pf=200.0,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             f_a_cs_void=0.29999999999999999,
             n_cs_pf_coils=7,
             n_pf_coil_turns=np.array(
@@ -2536,7 +2537,7 @@ class Acc2222Param(NamedTuple):
             supercond_cost_model=1,
             j_crit_str_cs=100.0,
             j_crit_str_pf=200.0,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             f_a_cs_void=0.29999999999999999,
             n_cs_pf_coils=7,
             n_pf_coil_turns=np.array(
diff --git a/tests/unit/models/test_pfcoil.py b/tests/unit/models/test_pfcoil.py
index 1bf393f0e..cd1cf121c 100644
--- a/tests/unit/models/test_pfcoil.py
+++ b/tests/unit/models/test_pfcoil.py
@@ -17,7 +17,10 @@
 from numpy.testing import assert_array_almost_equal
 
 from process.core import constants
-from process.data_structure.pfcoil_variables import N_PF_COILS_IN_GROUP_MAX
+from process.data_structure.pfcoil_variables import (
+    N_PF_COILS_IN_GROUP_MAX,
+    PFConductorModel,
+)
 from process.models.pfcoil import (
     CSEUDEMOTurnGeometry,
     CSGeometry,
@@ -2483,7 +2486,9 @@ def test_pfcoil(monkeypatch, pfcoil):
         pfcoil.data.pf_coil, "zref", [3.6, 1.2, 2.5, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0]
     )
     monkeypatch.setattr(pfcoil.data.pf_coil, "m_pf_coil_max", 0.0)
-    monkeypatch.setattr(pfcoil.data.pf_coil, "i_pf_conductor", 0)
+    monkeypatch.setattr(
+        pfcoil.data.pf_coil, "i_pf_conductor", PFConductorModel.SUPERCONDUCTING
+    )
     monkeypatch.setattr(pfcoil.data.pf_coil, "alfapf", 5.0e-10)
     monkeypatch.setattr(pfcoil.data.pf_coil, "n_pf_cs_plasma_circuits", 8)
     monkeypatch.setattr(pfcoil.data.pf_coil, "rho_pf_coil", 2.5e-8)
@@ -2593,7 +2598,9 @@ def test_ohcalc(monkeypatch, reinitialise_error_module, cs_coil):
     monkeypatch.setattr(cs_coil.data.pf_coil, "b_cs_peak_pulse_start", 1.4e1)
     monkeypatch.setattr(cs_coil.data.pf_coil, "j_cs_critical_flat_top_end", 4.070e7)
     monkeypatch.setattr(cs_coil.data.pf_coil, "temp_cs_superconductor_margin", 1.5)
-    monkeypatch.setattr(cs_coil.data.pf_coil, "i_pf_conductor", 0)
+    monkeypatch.setattr(
+        cs_coil.data.pf_coil, "i_pf_conductor", PFConductorModel.SUPERCONDUCTING
+    )
     monkeypatch.setattr(cs_coil.data.pf_coil, "j_pf_wp_critical", np.full(22, 0.0))
     monkeypatch.setattr(cs_coil.data.pf_coil, "rho_pf_coil", 2.8e-8)
     monkeypatch.setattr(cs_coil.data.pf_coil, "f_a_pf_coil_void", np.full(22, 0.3))
diff --git a/tests/unit/models/test_pulse.py b/tests/unit/models/test_pulse.py
index 8902823d4..a8214de23 100644
--- a/tests/unit/models/test_pulse.py
+++ b/tests/unit/models/test_pulse.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+from process.data_structure.pfcoil_variables import PFConductorModel
+
 
 @pytest.fixture
 def pulse(process_models):
@@ -59,7 +61,7 @@ class TohswgParam(NamedTuple):
             t_current_ramp_up_min=0,
             vpfskv=0,
             n_pf_cs_plasma_circuits=8,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             n_cs_pf_coils=7,
             p_cs_resistive_flat_top=0,
             ind_pf_cs_plasma_mutual=np.array(
@@ -617,7 +619,7 @@ class TohswgParam(NamedTuple):
             t_current_ramp_up_min=-526.67247746645455,
             vpfskv=20,
             n_pf_cs_plasma_circuits=8,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             n_cs_pf_coils=7,
             p_cs_resistive_flat_top=0,
             ind_pf_cs_plasma_mutual=np.array(
diff --git a/tests/unit/models/test_structure.py b/tests/unit/models/test_structure.py
index 816ee4a62..b8353f6ad 100644
--- a/tests/unit/models/test_structure.py
+++ b/tests/unit/models/test_structure.py
@@ -2,6 +2,7 @@
 
 import pytest
 
+from process.data_structure.pfcoil_variables import PFConductorModel
 from process.models.structure import Structure
 
 
@@ -33,7 +34,7 @@ def test_structure(structure):
             akappa=1.848,
             b0=5.3292,
             i_tf_sup=1,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             tf_h_width=15.337464674334223,
             tfhmax=9.0730900215620327,
             shldmass=2294873.8131476026,
diff --git a/tests/unit/models/tfcoil/test_tfcoil.py b/tests/unit/models/tfcoil/test_tfcoil.py
index 5df3a9f14..da98774ee 100644
--- a/tests/unit/models/tfcoil/test_tfcoil.py
+++ b/tests/unit/models/tfcoil/test_tfcoil.py
@@ -11,6 +11,7 @@
 
 import process.models.tfcoil.base as tfcoil_module
 from process.data_structure.build_variables import TFCSRadialConfiguration
+from process.data_structure.pfcoil_variables import PFConductorModel
 
 
 @pytest.fixture
@@ -1030,7 +1031,7 @@ class StressclParam(NamedTuple):
             f_a_tf_turn_cable_copper=0.80884,
             str_wp=0,
             n_tf_wp_stress_layers=5,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             f_a_cs_turn_steel=0.57874999999999999,
             f_z_cs_tf_internal=0.90000000000000002,
             j_cs_flat_top_end=20726000,
@@ -1147,7 +1148,7 @@ class StressclParam(NamedTuple):
             f_a_tf_turn_cable_copper=0.80884,
             str_wp=0.0015619754370069119,
             n_tf_wp_stress_layers=5,
-            i_pf_conductor=0,
+            i_pf_conductor=PFConductorModel.SUPERCONDUCTING,
             f_a_cs_turn_steel=0.57874999999999999,
             f_z_cs_tf_internal=0.90000000000000002,
             j_cs_flat_top_end=20726000,