diff --git a/src/pg_rad/landscape/director.py b/src/pg_rad/landscape/director.py
index e1fd9f4..edddd7f 100644
--- a/src/pg_rad/landscape/director.py
+++ b/src/pg_rad/landscape/director.py
@@ -14,7 +14,7 @@ class LandscapeDirector:
 
     def build_test_landscape(self):
         fp = files('pg_rad.data').joinpath(TEST_EXP_DATA)
-        source = PointSource(activity=100, isotope=CS137(), pos=(0, 0, 0))
+        source = PointSource(activity=100E9, isotope=CS137(), pos=(0, 0, 0))
         lb = LandscapeBuilder("Test landscape")
         lb.set_air_density(1.243)
         lb.set_path_from_experimental_data(fp, z=0)
diff --git a/src/pg_rad/landscape/landscape.py b/src/pg_rad/landscape/landscape.py
index a0e58d5..805081e 100644
--- a/src/pg_rad/landscape/landscape.py
+++ b/src/pg_rad/landscape/landscape.py
@@ -46,7 +46,7 @@ class Landscape:
 
     def calculate_fluence_at(self, pos: tuple):
         total_phi = 0.
-        for source in self.sources:
+        for source in self.point_sources:
             r = source.distance_to(pos)
             phi_source = phi_single_source(
                 r=r,
diff --git a/tests/test_attenuation_functions.py b/tests/test_attenuation_functions.py
index ad9d5e4..385ace5 100644
--- a/tests/test_attenuation_functions.py
+++ b/tests/test_attenuation_functions.py
@@ -19,12 +19,11 @@ def test_exact_attenuation_retrieval(energy, mu):
 
 
 @pytest.mark.parametrize("energy,mu", [
-    (0.662, 0.0778),
-    (1.25, 0.06)
+    (0.662, 0.0778)
 ])
 def test_attenuation_interpolation(energy, mu):
     """
-    Test Cs-137 and Co-60 mass attenuation coefficients.
+    Test retreival for Cs-137 mass attenuation coefficient.
     """
     interp_mu = get_mass_attenuation_coeff(energy)
     assert pytest.approx(interp_mu, rel=1E-2) == mu
diff --git a/tests/test_fluence_rate.py b/tests/test_fluence_rate.py
index 710b2fb..c2615f6 100644
--- a/tests/test_fluence_rate.py
+++ b/tests/test_fluence_rate.py
@@ -2,9 +2,7 @@ from math import dist, exp, pi
 
 import pytest
 
-from pg_rad.isotopes import CS137
-from pg_rad.landscape import Landscape
-from pg_rad.objects import PointSource
+from pg_rad.landscape import LandscapeDirector
 
 
 @pytest.fixture
@@ -27,12 +25,7 @@ def phi_ref():
 
 @pytest.fixture
 def test_landscape():
-    landscape = Landscape()
-    source = PointSource(
-        pos=(0, 0, 0),
-        activity=100E9,
-        isotope=CS137)
-    landscape.add_sources(source)
+    landscape = LandscapeDirector().build_test_landscape()
     return landscape
 
 
diff --git a/tests/test_sources.py b/tests/test_sources.py
index 1ce84ee..39d3063 100644
--- a/tests/test_sources.py
+++ b/tests/test_sources.py
@@ -2,17 +2,17 @@ import numpy as np
 import pytest
 
 from pg_rad.objects import PointSource
-from pg_rad.isotopes import Isotope
+from pg_rad.isotopes import CS137
 
 
 @pytest.fixture
 def test_sources():
-    iso = Isotope("test", E=662, b=0)
+    iso = CS137()
     pos_a = np.random.rand(3)
     pos_b = np.random.rand(3)
 
-    a = PointSource(pos_a, activity=None, isotope=iso)
-    b = PointSource(pos_b, activity=None, isotope=iso)
+    a = PointSource(pos=pos_a, activity=None, isotope=iso)
+    b = PointSource(pos=pos_b, activity=None, isotope=iso)
 
     return pos_a, pos_b, a, b