diff --git a/scripts/Diffraction/isis_powder/routines/focus.py b/scripts/Diffraction/isis_powder/routines/focus.py
index ae7eda231e8a8175d2e49eace35c4e883de21a64..a72d912e0e23e748e3ad0b5a3ee0def7d317ccc9 100644
--- a/scripts/Diffraction/isis_powder/routines/focus.py
+++ b/scripts/Diffraction/isis_powder/routines/focus.py
@@ -113,6 +113,8 @@ def _batched_run_focusing(instrument, perform_vanadium_norm, run_number_string,
 
 def _divide_one_spectrum_by_spline(spectrum, spline):
     rebinned_spline = mantid.RebinToWorkspace(WorkspaceToRebin=spline, WorkspaceToMatch=spectrum, StoreInADS=False)
+    rebinned_spline = mantid.ReplaceSpecialValues(rebinned_spline,SmallNumberThreshold=0, SmallNumberValue=1,
+                                                  StoreInADS=False)
     divided = mantid.Divide(LHSWorkspace=spectrum, RHSWorkspace=rebinned_spline, OutputWorkspace=spectrum)
     return divided