diff --git a/src/recon_test/test_MLEstimateComponentBasedNormalisation.cxx b/src/recon_test/test_MLEstimateComponentBasedNormalisation.cxx
index e0561d488..34a1ce7b5 100644
--- a/src/recon_test/test_MLEstimateComponentBasedNormalisation.cxx
+++ b/src/recon_test/test_MLEstimateComponentBasedNormalisation.cxx
@@ -76,6 +76,13 @@ class MLEstimateComponentBasedNormalisationTest : public RunTests
                                                               do_save_to_file);
     ml_estimator.process();
 
+    // Check the efficiencies, with measured data as uniform 1s and model data as uniform 2s, expect this to be ~0.707
+    auto efficiencies = ml_estimator.get_efficiencies();
+    check_if_less(efficiencies.find_max(), 0.75, "The max value of the efficiencies is greater than expected");
+    check_if_less(0.65, efficiencies.find_max(), "The max value of the efficiencies is less than expected");
+    check_if_less(efficiencies.find_min(), 0.75, "The min value of the efficiencies is greater than expected");
+    check_if_less(0.65, efficiencies.find_min(), "The min value of the efficiencies is less than expected");
+
     auto bin_normalization = ml_estimator.construct_bin_normfactors_from_components();
     bin_normalization.set_up(measured_projdata->get_exam_info_sptr(), measured_projdata->get_proj_data_info_sptr());