diff --git a/process/availability.py b/process/availability.py
index 6dd2259842..43c0499c28 100644
--- a/process/availability.py
+++ b/process/availability.py
@@ -1,7 +1,6 @@
 import logging
 import math
 
-import numpy as np
 from scipy.special import comb as combinations
 
 from process import constants
@@ -110,9 +109,13 @@ def avail(self, output: bool):
                 # Calculate blanket lifetime using neutron fluence model (ibkt_life=0)
                 # or DEMO fusion power model (ibkt_life=1)
                 if cv.ibkt_life == 0:
-                    fwbsv.life_blkt_fpy = min(
-                        (cv.abktflnc / np.asarray(pv.pflux_fw_neutron_mw)).item(),
-                        cv.life_plant,
+                    fwbsv.life_blkt_fpy = (
+                        cv.life_plant
+                        if pv.pflux_fw_neutron_mw == 0.0
+                        else min(
+                            (cv.abktflnc / pv.pflux_fw_neutron_mw),
+                            cv.life_plant,
+                        )
                     )
                 else:
                     fwbsv.life_blkt_fpy = min(
@@ -1355,11 +1358,13 @@ def cp_lifetime():
         # SC magnets CP lifetime
         # Rem : only the TF maximum fluence is considered for now
         if tfv.i_tf_sup == 1:
-            cplife = min(
-                (
-                    ctv.nflutfmax / (np.asarray(fwbsv.neut_flux_cp) * YEAR_SECONDS)
-                ).item(),
-                cv.life_plant,
+            cplife = (
+                cv.life_plant
+                if fwbsv.neut_flux_cp <= 0.0
+                else min(
+                    (ctv.nflutfmax / (fwbsv.neut_flux_cp * YEAR_SECONDS)),
+                    cv.life_plant,
+                )
             )
 
         # Aluminium/Copper magnets CP lifetime
diff --git a/tests/unit/test_availability.py b/tests/unit/test_availability.py
index bcf3b2dc81..c0dcc121c5 100644
--- a/tests/unit/test_availability.py
+++ b/tests/unit/test_availability.py
@@ -99,6 +99,7 @@ def test_avail_1(monkeypatch, availability):
     monkeypatch.setattr(cv, "uufw", 0.8)
     monkeypatch.setattr(cv, "uumag", 0.9)
     monkeypatch.setattr(cv, "uuves", 0.11)
+    monkeypatch.setattr(tv, "t_plant_pulse_total", 1e4)
 
     availability.avail(output=False)
     cfactr_obs = cv.f_t_plant_available
@@ -221,6 +222,7 @@ def calc_u_planned_fix(request, monkeypatch):
     monkeypatch.setattr(cv, "cplife", 0.0)
     monkeypatch.setattr(cv, "cpstflnc", param["cpstflnc"])
     monkeypatch.setattr(cv, "num_rh_systems", param["num_rh_systems"])
+    monkeypatch.setattr(fwbsv, "neut_flux_cp", 1e18)
 
     # Return the expected result for the given parameter list
     return param["expected"]
diff --git a/tests/unit/test_current_drive.py b/tests/unit/test_current_drive.py
index d6b9792ed9..fde5a6539d 100644
--- a/tests/unit/test_current_drive.py
+++ b/tests/unit/test_current_drive.py
@@ -150,6 +150,8 @@ def test_cudriv_primary_neutral_beam(current_drive):
     physics_variables.m_beam_amu = 2.0
     physics_variables.temp_plasma_electron_density_weighted_kev = 10.0
     physics_variables.n_charge_plasma_effective_vol_avg = 2.0
+    physics_variables.dlamie = 1.0
+    physics_variables.n_charge_plasma_effective_mass_weighted_vol_avg = 0.4
     current_drive.cudriv()
 
     assert current_drive_variables.eta_cd_hcd_primary == pytest.approx(
diff --git a/tests/unit/test_plasma_profiles.py b/tests/unit/test_plasma_profiles.py
index 3d08682b0f..8387c3ca8a 100644
--- a/tests/unit/test_plasma_profiles.py
+++ b/tests/unit/test_plasma_profiles.py
@@ -469,6 +469,8 @@ def test_plasma_profiles(plasmaprofilesparam, monkeypatch):
 
     monkeypatch.setattr(physics_variables, "rminor", plasmaprofilesparam.rminor)
 
+    monkeypatch.setattr(physics_variables, "a_plasma_poloidal", 4.0)
+
     plasmaprofile = PlasmaProfile()
     plasmaprofile.run()