diff --git a/LSL2/STPROC/COMM_QA_MET_RESULT.txt b/LSL2/STPROC/COMM_QA_MET_RESULT.txt
index d3f9ec2..d5ac9cf 100644
--- a/LSL2/STPROC/COMM_QA_MET_RESULT.txt
+++ b/LSL2/STPROC/COMM_QA_MET_RESULT.txt
@@ -352,7 +352,7 @@ Refresh:
 				end
 				Set_Property(@WINDOW:'.MET_STD_RESULT', 'DEFPROP', StdDev)
 				If StdDev GT MetStdMax then
-					Backcolor = RED$
+				    If MetStdMax NE '' then Backcolor = RED$ else Backcolor = GREY$
 				end else
 					Backcolor = GREEN$
 				end
@@ -483,7 +483,7 @@ Refresh:
 					end
 					Set_Property(@WINDOW:'.MET_STD_RESULT', 'DEFPROP', StdDev)
 					If StdDev GT MetStdMax then
-						Backcolor = RED$
+					    If MetStdMax NE '' then Backcolor = RED$ else Backcolor = GREY$
 					end else
 						Backcolor = GREEN$
 					end
@@ -751,8 +751,9 @@ ResultLF:
     END
     
 	IF (MetStdResult NE '') THEN
-		If (MetStdResult > MetStdMax) then 
-			Set_Property(@WINDOW:'.MET_STD_RESULT','BACKCOLOR',RED$)
+		If (MetStdResult > MetStdMax) then
+		    If MetStdMax NE '' then Set_Property(@WINDOW:'.MET_STD_RESULT','BACKCOLOR',RED$) else Set_Property(@WINDOW:'.MET_STD_RESULT','BACKCOLOR', GREY$)
+			
 		end else
 			Set_Property(@WINDOW:'.MET_STD_RESULT','BACKCOLOR',GREEN$)
 		END
@@ -1133,3 +1134,4 @@ PubSaveClick:
     
 RETURN
 
+
diff --git a/LSL2/STPROC/SIGNATURE_SERVICES.txt b/LSL2/STPROC/SIGNATURE_SERVICES.txt
index 1cf4bd2..c4118d1 100644
--- a/LSL2/STPROC/SIGNATURE_SERVICES.txt
+++ b/LSL2/STPROC/SIGNATURE_SERVICES.txt
@@ -2505,16 +2505,6 @@ Service QAMetSigReady(RDSNo, QAStage=QA_STAGES, Slot=SLOTS, WOMatQAKey)
                             Case ( (MetResult LT MetMin) or (MetResult GT MetMax) )
                                 ErrorMessage = 'Error in ':Service:' service. Metrology result is out of spec for stage ':QAStage:' slot ':Slot:'.'
                         End Case
-                        // Compare Std Dev Result to Std Dev Max
-                        StdDevResult = WOMatQARec<WO_MAT_QA_STD_RESULT$, vPos>
-                        StdDevMax    = WOMatQARec<WO_MAT_QA_STD_MAX$, vPos>
-                        Begin Case
-                            Case StdDevResult EQ ''
-                                // Std Dev data is not always supplied.
-                                Null
-                            Case StdDevResult GT StdDevMax
-                                ErrorMessage = 'Error in ':Service:' service. StdDev exceeds spec for stage ':QAStage:'.'
-                        End Case
                         
                         If TestProp EQ 'THICK' then
                             // Ensure makeup wafer thickness values are in spec and that at least one wafer
@@ -2933,3 +2923,4 @@ GetMostRecentSig:
     
 return
 
+