diff --git a/cara/models.py b/cara/models.py
index 2c65c770..9d7898fd 100644
--- a/cara/models.py
+++ b/cara/models.py
@@ -1357,22 +1357,20 @@ class ExposureModel:
                 # particle diameters (doing things in another order would
                 # lead to wrong results for the probability of infection).
                 this_deposited_exposure = (np.array(short_range_jet_exposure
-                    * fdep).mean()/dilution
+                    * fdep).mean()
                     - np.array(short_range_lr_exposure * fdep).mean()
-                    * self.concentration_model.infected.activity.exhalation_rate
-                    /dilution)
+                    * self.concentration_model.infected.activity.exhalation_rate)
             else:
                 # in the case of a single diameter or no diameter defined,
                 # one should not take any mean at this stage.
-                this_deposited_exposure = (short_range_jet_exposure
-                    * fdep/dilution
+                this_deposited_exposure = (short_range_jet_exposure * fdep
                     - short_range_lr_exposure * fdep
-                    * self.concentration_model.infected.activity.exhalation_rate
-                    /dilution)
+                    * self.concentration_model.infected.activity.exhalation_rate)
 
             # multiply by the (diameter-independent) inhalation rate
             deposited_exposure += (this_deposited_exposure *
-                                   interaction.activity.inhalation_rate)
+                                   interaction.activity.inhalation_rate
+                                   /dilution)
 
         # then we multiply by diameter-independent quantities: viral load
         # and fraction of infected virions