diff --git a/chem/module_optical_averaging.F b/chem/module_optical_averaging.F
index 773b7bdcaf..5b7403b77f 100644
--- a/chem/module_optical_averaging.F
+++ b/chem/module_optical_averaging.F
@@ -4695,6 +4695,24 @@ subroutine mieaer( &
                 endif
           !ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 
+! check for refr and refi outside of lookup table range to prevent unstable extrapolation 'binterp' below
+          if (refr < refrtabsw(1,ns)) then
+             refr = refrtabsw(1,ns)
+             write(*,*), 'Warning: refr is smaller than lookup table range and reset to minimum bound at SW band ', ns
+          endif
+          if (refr > refrtabsw(prefr,ns)) then
+             refr = refrtabsw(prefr,ns)
+             write(*,*), 'Warning: refr is larger than lookup table range and reset to maximum bound at SW band ', ns
+          endif
+          if (refi < refitabsw(1,ns)) then
+             refi = refitabsw(1,ns)
+             write(*,*), 'Warning: refi is smaller than lookup table range and reset to minimum bound at SW band ', ns
+          endif
+          if (refi > refitabsw(prefi,ns)) then
+             refi = refitabsw(prefi,ns)
+             write(*,*), 'Warning: refi is larger than lookup table range and reset to maximum bound at SW band ', ns
+          endif
+
 ! interpolate coefficients linear in refractive index
 ! first call calcs itab,jtab,ttab,utab
                   itab=0
@@ -4952,6 +4970,24 @@ subroutine mieaer( &
                 endif
           !ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
 
+! check for refr and refi outside of lookup table range to prevent unstable extrapolation 'binterp' below
+          if (refr < refrtablw(1,ns)) then
+             refr = refrtablw(1,ns)
+             write(*,*), 'Warning: refr is smaller than lookup table range and reset to minimum bound at LW band ', ns
+          endif
+          if (refr > refrtablw(prefr,ns)) then
+             refr = refrtablw(prefr,ns)
+             write(*,*), 'Warning: refr is larger than lookup table range and reset to maximum bound at LW band ', ns
+          endif
+          if (refi < refitablw(1,ns)) then    
+             refi = refitablw(1,ns)
+             write(*,*), 'Warning: refi is smaller than lookup table range and reset to minimum bound at LW band ', ns
+          endif
+          if (refi > refitablw(prefi,ns)) then
+             refi = refitablw(prefi,ns)
+             write(*,*), 'Warning: refi is larger than lookup table range and reset to maximum bound at LW band ', ns
+          endif
+
 ! interpolate coefficients linear in refractive index
 ! first call calcs itab,jtab,ttab,utab
                   itab=0