diff --git a/code/DAMASK_spectral_solverAL.f90 b/code/DAMASK_spectral_solverAL.f90
index a20d112ce..de26a53a8 100644
--- a/code/DAMASK_spectral_solverAL.f90
+++ b/code/DAMASK_spectral_solverAL.f90
@@ -34,6 +34,7 @@ module DAMASK_spectral_solverAL
    tSolutionState
  
  implicit none
+ private
 #include <finclude/petscsys.h>
 #include <finclude/petscdmda.h>
 #include <finclude/petscsnes.h>
diff --git a/code/DAMASK_spectral_solverBasic.f90 b/code/DAMASK_spectral_solverBasic.f90
index fa8a8850c..d80aa196f 100644
--- a/code/DAMASK_spectral_solverBasic.f90
+++ b/code/DAMASK_spectral_solverBasic.f90
@@ -36,6 +36,7 @@ module DAMASK_spectral_SolverBasic
    tSolutionState
  
  implicit none
+ private
  character (len=*), parameter, public :: &
    DAMASK_spectral_SolverBasic_label = 'basic'
 
diff --git a/code/DAMASK_spectral_utilities.f90 b/code/DAMASK_spectral_utilities.f90
index 3e97713a0..9c43d9b13 100644
--- a/code/DAMASK_spectral_utilities.f90
+++ b/code/DAMASK_spectral_utilities.f90
@@ -31,6 +31,7 @@ module DAMASK_spectral_utilities
    pInt
 
  implicit none
+ private
 #ifdef PETSc
 #include <finclude/petscsys.h>
 #endif
@@ -922,7 +923,7 @@ real(pReal) function utilities_getFilter(k)
  utilities_getFilter = 1.0_pReal
 
  select case (myfilter)
-    case ('none')
+    case ('none')                                                                                   !< default is already nothing (1.0_pReal)
     case ('cosine')                                                                                 !< cosine curve with 1 for avg and zero for highest freq
       utilities_getFilter = (1.0_pReal + cos(PI*k(3)/res(3))) &
                            *(1.0_pReal + cos(PI*k(2)/res(2))) &
@@ -939,12 +940,12 @@ end function utilities_getFilter
 !--------------------------------------------------------------------------------------------------
 subroutine utilities_destroy()
  use math
- implicit none
- if (debugDivergence) call fftw_destroy_plan(plan_divergence)
 
+ implicit none
+
+ if (debugDivergence) call fftw_destroy_plan(plan_divergence)
  if (debugFFTW) call fftw_destroy_plan(plan_scalarField_forth)
  if (debugFFTW) call fftw_destroy_plan(plan_scalarField_back)
-  
  call fftw_destroy_plan(plan_forward)
  call fftw_destroy_plan(plan_backward)
 
diff --git a/code/numerics.f90 b/code/numerics.f90
index da15a897f..6aaee4dda 100644
--- a/code/numerics.f90
+++ b/code/numerics.f90
@@ -41,8 +41,8 @@ module numerics
    nCryst                     = 20_pInt, &                                                          !< crystallite loop limit (only for debugging info, loop limit is determined by "subStepMinCryst")
    nState                     = 10_pInt, &                                                          !< state loop limit
    nStress                    = 40_pInt, &                                                          !< stress loop limit
-   pert_method                =  1_pInt                                                             !< method used in perturbation technique for tangent
-   fixedSeed                  =  0_pInt                                                             !< fixed seeding for pseudo-random number generator, Default 0: use random seed
+   pert_method                =  1_pInt, &                                                          !< method used in perturbation technique for tangent
+   fixedSeed                  =  0_pInt, &                                                          !< fixed seeding for pseudo-random number generator, Default 0: use random seed
    DAMASK_NumThreadsInt       =  0_pInt                                                             !< value stored in environment variable DAMASK_NUM_THREADS, set to zero if no OpenMP directive
  integer(pInt), public :: &
    numerics_integrationMode   =  0_pInt                                                             !< integrationMode 1 = central solution ; integrationMode 2 = perturbation, Default 0: undefined, is not read from file